AeroElectric-Archive.digest.vol-mw

August 19, 2015 - October 19, 2015



      when it got pinched unknowingly in the backside of the crimpers.  Ooops....
      
      So my problem now is that my wires between my instrumentation and the the
      connections on my thermocouple are too short.  Thus I need to extend them.
      
      The thermocouples I'm installing now are EGT and CHT sensors from Alcor.
       (With a ring connectors).
      
      Questions:
      
      1) The sensors have ring connectors already installed.   I don't have the
      other ring connectors (matching metal) for them to join to.   Where can I
      buy these to crimp on or can I simply use my PIDG connectors?
      
      2) I'm assuming that if I use the correct metal the impact to reading would
      be very minor?
      
      3) I'm also assuming that these connectors are very expensive.  Yes?  No?
      Is there are cheaper way to join them?
      
      4) Finally, I've managed to lose a couple of the fiberglass sleeves.  Where
      can I buy those and is there a reason I can't just cover the connections in
      heat shrink?
      
      
      Thanks for your comments,
      Phil
      
________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: electrical system planning
At 11:21 PM 8/18/2015, you wrote: >The battery contactor pulls nearly a full amp. >Also it is very easy to shed unneeded load by >shutting=C2 the main down and going with the "E" bus. Z-12 doesn't give you the option of running with the battery contactor open . . . Z13-8 DID offer that mode . . . due to the limited output from the SD-8. Of course, it also offers a calculated plan-c for operating battery only. I once offered a Z-13/20 utilizing the SD-20 . . . kinda messy and I pulled it. I might do some asphalt-cogitation on another pass at it. In the mean time, Z-12 is exemplary of architectures flying on hundreds of TC aircraft of the production lines of Beech, Mooney, Piper et. als. . . . except their 'e-bus' is an (ugh!!) 'avionics-bus'. Bob . . . ________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Thermocouple Questions...
At 08:27 AM 8/19/2015, you wrote: >Hello, > >Last night I started connecting my Type-K >sensors up to the airplane instrumentation. >=C2 Trimming the single conductor leads from the >instrumentation to match the length of the leads >on the thermocouple. =C2 Then in the process of >crimping a wire I managed to cut one of the >leads when it got pinched unknowingly in the >backside of the crimpers.=C2 Ooops.... > >So my problem now is that my wires between my >instrumentation and the the connections on my >thermocouple are too short.=C2 Thus I need to extend them. > >The thermocouples I'm installing now are EGT and >CHT sensors from Alcor. =C2 (With a ring connectors). > >Questions: > >1) The sensors have ring connectors already >installed. =C2 I don't have the other ring >connectors (matching metal) for them to join to. >=C2 Where can I buy these to crimp on or can I simply use my PIDG connectors? For a short extension, where BOTH ends of the extension wire are in the same environmental temperature, you can use ordinary copper wire. The parasitic junctions added by the foreign alloy will cancel out each others effects. Use pidg splices to extend the damaged wire with copper . . . Use pidg terminals to mate with wires extending into the cockpit . . . Plain vanilla heat-shrink is fine. Bob . . . ________________________________________________________________________________
Date: Aug 19, 2015
From: "Ralph E. Capen" <recapen(at)earthlink.net>
Subject: Re: Thermocouple Questions...
Phil, My experiences..... I have used male/female spade connectors with heat-shrink sleeves. I soldered my connections as well since the wire used does nor have sufficient elasticity to create a physical/sealed connection. I used the same connections - and ordered spares from my equipment supplier - they should be able to tell you what they use and source. Metal to metal differences cancel out generally as long as both sides of the connection are in the same side of the firewall. The type (cost) of connector is not really important - consistency and vibration-free physical connection is important. I cover mine with heat-shrink to reduce the vibration potential. Ralph -----Original Message----- From: Phillip Perry Sent: Aug 19, 2015 9:27 AM Subject: AeroElectric-List: Thermocouple Questions... Hello, Last night I started connecting my Type-K sensors up to the airplane instrumentation. Trimming the single conductor leads from the instrumentation to match the length of the leads on the thermocouple. Then in the process of crimping a wire I managed to cut one of the leads when it got pinched unknowingly in the backside of the crimpers. Ooops.... So my problem now is that my wires between my instrumentation and the the connections on my thermocouple are too short. Thus I need to extend them. The thermocouples I'm installing now are EGT and CHT sensors from Alcor. (With a ring connectors). Questions: 1) The sensors have ring connectors already installed. I don't have the other ring connectors (matching metal) for them to join to. Where can I buy these to crimp on or can I simply use my PIDG connectors? 2) I'm assuming that if I use the correct metal the impact to reading would be very minor? 3) I'm also assuming that these connectors are very expensive. Yes? No? Is there are cheaper way to join them? 4) Finally, I've managed to lose a couple of the fiberglass sleeves. Where can I buy those and is there a reason I can't just cover the connections in heat shrink? Thanks for your comments,Phil ________________________________________________________________________________
Date: Aug 19, 2015
From: "Kent Ogden" <ogdenk(at)upstate.edu>
Subject: Antenna Question
I'm finishing up my RV-10 wings and would like to have (most) everything done before I move on. I am contemplating wingtip VOR antenna(s) and wonder if these can also be used for glideslope? I expect most navigation will be from gps but I would like to have an operating VOR as well. Thanks for any thoughts/comments. Kent ________________________________________________________________________________
From: ARGOLDMAN(at)aol.com
Date: Aug 19, 2015
Subject: Re: Antenna Question
The GS antenna is smaller than the VOR antenna so you can physically do it, however you can just use the VOR antenna with a splitter made for the purpose. You get a little loss, but I think it is trivial. Rich In a message dated 8/19/2015 9:30:56 A.M. Central Daylight Time, ogdenk(at)upstate.edu writes: I'm finishing up my RV-10 wings and would like to have (most) everything done before I move on. I am contemplating wingtip VOR antenna(s) and wonder if these can also be used for glideslope? I expect most navigation will be from gps but I would like to have an operating VOR as well. Thanks for any thoughts/comments. Kent ________________________________________________________________________________
Subject: Re: Thermocouple Questions...
From: "user9253" <fransew(at)gmail.com>
Date: Aug 19, 2015
For further reading: http://www.aeroelectric.com/articles/excerpt.pdf http://www.mglavionics.com/CHT_Parallel_Splice.pdf Whatever gets done to one thermocouple wire should also be done to the other wire, and in the same physical location. In other words, if one of a pair of thermocouple wires is spliced inside of the engine compartment, then its mate should also be spliced in that same location. The two splices should be at equal ambient temperatures. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446147#446147 ________________________________________________________________________________
From: Tcwtech <rnewman(at)tcwtech.com>
Subject: Re: Antenna Question
Date: Aug 19, 2015
Yes. A vor / glide slope splitter works. I have that exact setup in my r v-10. Bob Newman. > On Aug 19, 2015, at 10:29 AM, Kent Ogden wrote: > > I'm finishing up my RV-10 wings and would like to have (most) everything d one before I move on. I am contemplating wingtip VOR antenna(s) and wonder i f these can also be used for glideslope? I expect most navigation will be f rom gps but I would like to have an operating VOR as well. > > Thanks for any thoughts/comments. > > Kent > > > > > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > ________________________________________________________________________________
From: Jared Yates <email(at)jaredyates.com>
Date: Aug 19, 2015
Subject: Re: Thermocouple Questions...
I had trouble getting a good connection with crimp-on terminals, so I tried Omega connectors. Here are the details: http://bearhawkblue.com/replacing-the-oem-dynon-thermocouple-connectors-with-omega-connectors/ All of my intermittent readings went away when I switched to these. > On Aug 19, 2015, at 10:15, Ralph E. Capen wrote: > > > Phil, > > My experiences..... > > I have used male/female spade connectors with heat-shrink sleeves. I soldered my connections as well since the wire used does nor have sufficient elasticity to create a physical/sealed connection. I used the same connections - and ordered spares from my equipment supplier - they should be able to tell you what they use and source. > > Metal to metal differences cancel out generally as long as both sides of the connection are in the same side of the firewall. > > The type (cost) of connector is not really important - consistency and vibration-free physical connection is important. > > I cover mine with heat-shrink to reduce the vibration potential. > > Ralph > > > > -----Original Message----- > > From: Phillip Perry > > Sent: Aug 19, 2015 9:27 AM > > To: aeroelectric-list(at)matronics.com > > Subject: AeroElectric-List: Thermocouple Questions... > > > > Hello, > Last night I started connecting my Type-K sensors up to the airplane instrumentation. Trimming the single conductor leads from the instrumentation to match the length of the leads on the thermocouple. Then in the process of crimping a wire I managed to cut one of the leads when it got pinched unknowingly in the backside of the crimpers. Ooops.... > So my problem now is that my wires between my instrumentation and the the connections on my thermocouple are too short. Thus I need to extend them. > The thermocouples I'm installing now are EGT and CHT sensors from Alcor. (With a ring connectors). > Questions: > 1) The sensors have ring connectors already installed. I don't have the other ring connectors (matching metal) for them to join to. Where can I buy these to crimp on or can I simply use my PIDG connectors? > 2) I'm assuming that if I use the correct metal the impact to reading would be very minor? > 3) I'm also assuming that these connectors are very expensive. Yes? No? Is there are cheaper way to join them? > 4) Finally, I've managed to lose a couple of the fiberglass sleeves. Where can I buy those and is there a reason I can't just cover the connections in heat shrink? > > Thanks for your comments,Phil > > > > > > > > > > > > ________________________________________________________________________________
Date: Aug 19, 2015
Subject: Re: electrical system master contactor
From: Bill Allen <billallensworld(at)gmail.com>
Hi, The master contactor pulls about 1.5 amps which is more than many components that "work for their living" Is there any reason why a heavy duty manual contactor could not be used instead of the traditional solenoid contactor, like this; http://tinyurl.com/nupw5xu Bill Allen LongEz160 N99BA FD51 CZ4 G-BYLZ EGBJ On 19 August 2015 at 15:00, Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > At 11:21 PM 8/18/2015, you wrote: > > The battery contactor pulls nearly a full amp. Also it is very easy to > shed unneeded load by shutting=C3=82 the main down and going with the "E " bus. > > > Z-12 doesn't give you the option of running > with the battery contactor open . . . Z13-8 > DID offer that mode . . . due to the limited > output from the SD-8. Of course, it also offers > a calculated plan-c for operating battery > only. > > I once offered a Z-13/20 utilizing the > SD-20 . . . kinda messy and I pulled it. > I might do some asphalt-cogitation on another > pass at it. In the mean time, Z-12 is > exemplary of architectures flying on hundreds > of TC aircraft of the production lines of > Beech, Mooney, Piper et. als. . . . except > their 'e-bus' is an (ugh!!) 'avionics-bus'. > > > Bob . . . > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- Bill Allen LongEz160 N99BA FD51 CZ4 G-BYLZ EGBJ ________________________________________________________________________________
Subject: Re: Antenna Question
From: Kelly McMullen <kellym(at)aviating.com>
Date: Aug 19, 2015
Depending on the navcom you have, some have internal splitters and just need VOR antenna connection On 8/19/2015 7:52 AM, Tcwtech wrote: > Yes. A vor / glide slope splitter works. I have that exact setup > in my rv-10. > > Bob Newman. > > On Aug 19, 2015, at 10:29 AM, Kent Ogden > wrote: > >> I'm finishing up my RV-10 wings and would like to have (most) >> everything done before I move on. I am contemplating wingtip VOR >> antenna(s) and wonder if these can also be used for glideslope? I >> expect most navigation will be from gps but I would like to have an >> operating VOR as well. >> Thanks for any thoughts/comments. >> Kent >> >> ** > --> http://www.matronics.com/Navigator?AeroElectric-List > http://www.matronics.com/contribution > <3D%22http://www.matronics.com/contribution%22> > * ________________________________________________________________________________
Date: Aug 19, 2015
From: "Ralph E. Capen" <recapen(at)earthlink.net>
Subject: Re: Thermocouple Questions...
Good info - thanks! -----Original Message----- >From: Jared Yates <email(at)jaredyates.com> >Sent: Aug 19, 2015 11:05 AM >To: "aeroelectric-list(at)matronics.com" >Subject: Re: AeroElectric-List: Thermocouple Questions... > > >I had trouble getting a good connection with crimp-on terminals, so I tried Omega connectors. Here are the details: >http://bearhawkblue.com/replacing-the-oem-dynon-thermocouple-connectors-with-omega-connectors/ >All of my intermittent readings went away when I switched to these. > > >> On Aug 19, 2015, at 10:15, Ralph E. Capen wrote: >> >> >> Phil, >> >> My experiences..... >> >> I have used male/female spade connectors with heat-shrink sleeves. I soldered my connections as well since the wire used does nor have sufficient elasticity to create a physical/sealed connection. I used the same connections - and ordered spares from my equipment supplier - they should be able to tell you what they use and source. >> >> Metal to metal differences cancel out generally as long as both sides of the connection are in the same side of the firewall. >> >> The type (cost) of connector is not really important - consistency and vibration-free physical connection is important. >> >> I cover mine with heat-shrink to reduce the vibration potential. >> >> Ralph >> >> >> >> -----Original Message----- >> >> From: Phillip Perry >> >> Sent: Aug 19, 2015 9:27 AM >> >> To: aeroelectric-list(at)matronics.com >> >> Subject: AeroElectric-List: Thermocouple Questions... >> >> >> >> Hello, >> Last night I started connecting my Type-K sensors up to the airplane instrumentation. Trimming the single conductor leads from the instrumentation to match the length of the leads on the thermocouple. Then in the process of crimping a wire I managed to cut one of the leads when it got pinched unknowingly in the backside of the crimpers. Ooops.... >> So my problem now is that my wires between my instrumentation and the the connections on my thermocouple are too short. Thus I need to extend them. >> The thermocouples I'm installing now are EGT and CHT sensors from Alcor. (With a ring connectors). >> Questions: >> 1) The sensors have ring connectors already installed. I don't have the other ring connectors (matching metal) for them to join to. Where can I buy these to crimp on or can I simply use my PIDG connectors? >> 2) I'm assuming that if I use the correct metal the impact to reading would be very minor? >> 3) I'm also assuming that these connectors are very expensive. Yes? No? Is there are cheaper way to join them? >> 4) Finally, I've managed to lose a couple of the fiberglass sleeves. Where can I buy those and is there a reason I can't just cover the connections in heat shrink? >> >> Thanks for your comments,Phil >> >> >> >> >> >> >> >> >> >> >> >> > > ________________________________________________________________________________
From: Justin Jones <jmjones2000(at)mindspring.com>
Date: Aug 19, 2015
Subject: Re: electrical system master contactor
Electrically there is no reason a manual contactor would not work. The mast er contractor will go dead and shut the battery off from the rest of the sys tem if the control voltage is cut off (such as a crash). The mechanical swit ch may not. Access is the other consideration. If the battery is on the forward side of t he firewall you have 2 options. Put it close to the pilot or close to the ba ttery. Neither choice is good. If you put it near the pilot, you have a good amount of rather large gauge wire left unprotected. If you put it near the b attery, you may not have immediate access to it if you need it. You may be a ble to connect a lever or cable to the switch that can bring control into th e cockpit but that adds weight, complexity, and another component susceptibl e to failure. The solution I came up with is the solid state master relay from Waytek Wire . http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/ It draws .125ma of current and is good for 300A continuous. Also rated at 50 0A for 1 second. It is comparable in weight to a legacy master contactor, and it's heat sink i s made from aluminum. The battery charges perfectly through the relay and I have encountered zero i ssues with it. It's about twice the cost of a quality legacy contactor, with a rating of millions of cycles. Cutting edge technology. Justin > On Aug 19, 2015, at 11:28, Bill Allen wrote: > > Hi, > > The master contactor pulls about 1.5 amps which is more than many componen ts that "work for their living" > > Is there any reason why a heavy duty manual contactor could not be used in stead of the traditional solenoid contactor, like this; > > http://tinyurl.com/nupw5xu > > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > >> On 19 August 2015 at 15:00, Robert L. Nuckolls, III <nuckolls.bob@aeroele ctric.com> wrote: >> At 11:21 PM 8/18/2015, you wrote: >> >>> The battery contactor pulls nearly a full amp. Also it is very easy to s hed unneeded load by shutting=C3=82 the main down and going with the "E" bu s. >> >> Z-12 doesn't give you the option of running >> with the battery contactor open . . . Z13-8 >> DID offer that mode . . . due to the limited >> output from the SD-8. Of course, it also offers >> a calculated plan-c for operating battery >> only. >> >> I once offered a Z-13/20 utilizing the >> SD-20 . . . kinda messy and I pulled it. >> I might do some asphalt-cogitation on another >> pass at it. In the mean time, Z-12 is >> exemplary of architectures flying on hundreds >> of TC aircraft of the production lines of >> Beech, Mooney, Piper et. als. . . . except >> their 'e-bus' is an (ugh!!) 'avionics-bus'. >> >> >> Bob . . . >> >> >> >> ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-Li st >> tp://forums.matronics.com >> _blank">http://www.matronics.com/contribution >> > > > > -- > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > ________________________________________________________________________________
Date: Aug 19, 2015
From: Peter Pengilly <peter(at)sportingaero.com>
Subject: Re: Antenna Question
Yep, the SL-30 in my RV-6 works very well for localiser and glideslope from a wing tip antenna with a single feed. Peter On 19/08/2015 17:02, Kelly McMullen wrote: > > > Depending on the navcom you have, some have internal splitters and > just need VOR antenna connection > > On 8/19/2015 7:52 AM, Tcwtech wrote: >> Yes. A vor / glide slope splitter works. I have that exact setup >> in my rv-10. >> >> Bob Newman. >> >> On Aug 19, 2015, at 10:29 AM, Kent Ogden > > wrote: >> >>> I'm finishing up my RV-10 wings and would like to have (most) >>> everything done before I move on. I am contemplating wingtip VOR >>> antenna(s) and wonder if these can also be used for glideslope? I >>> expect most navigation will be from gps but I would like to have an >>> operating VOR as well. >>> Thanks for any thoughts/comments. >>> Kent >>> >>> ** >> --> http://www.matronics.com/Navigator?AeroElectric-List >> http://www.matronics.com/contribution >> <3D%22http://www.matronics.com/contribution%22> * > > ________________________________________________________________________________
Subject: Re: Anything 'unique' about incorporating EarthX?
From: "blues750" <den_beaulieu(at)yahoo.com>
Date: Aug 19, 2015
Earthx related, I'm not sure how "unique" this may be but...I'm hoping others will help clarify things for me. I also decided to go with Earthx batteries on my project, but am wrestling with a dilemma (or not) with regard to an overvoltage scenario from the PM 3 phase alternator and R/R electrical system. The Earthx battery has an onboard battery management system (BMS) to protect and balance the battery cells. When the BMS senses an overvoltage charging condition across multiple cells it will shut down the charge input AND cease output to any load on the battery until the situation is resolved. In talking with the tech engineer at Earthx, how fast this will happen depends on a few variables such at charge state of the individual cells, source voltage input, ambient temp, etc. but anything greater than about 15.3 volts has potential to trigger action by the BMS. So, here is my perceived dilemma with things. With a B&C overvoltage protection module (nominal trip voltage of 16.2 volts), I could have voltage to the battery greater than the BMS triiger voltage and have loss of battery power supply at the same time I have no alternator electrical source! [Shocked] [did I mention I'm running an ECU, fuel injected engine?] If this is truly the case, what are my options? I suspect one could just keep tabs on the alternator voltage output via a warning light and preempt the B&C or the BMS in the event of an overvoltage situation. But that doesn't sound ideal. Customize the B&C by adjusting the setpoint lower - e.g. 15 volts (concern about nuisance trips?) Or. one could go with different batteries and give up the lightweight advantage. I don't know if I truly do have a potential bad design or not? Anyone care to offer some insight? Thanks so very much Dave Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446161#446161 ________________________________________________________________________________
From: Ryan Brown <ribrdb(at)gmail.com>
Date: Aug 19, 2015
Subject: Re: electrical system planning
I'm looking at Z-12 Rev M and it does show an E-Bus Alternate Feed switch. I'm trying to understand why it's there. I imagine two possible reasons: 1) You could shut off the master switch to avoid the 1 amp contactor draw in main alternator out situtations 2) You could still run the e-bus if your master switch or contactor fails in flight. I don't know if that's the sort of failure that would happen in flight. But I'm not sure if either, both, or neither of those are why it's included in the diagram. On Wed, Aug 19, 2015 at 7:07 AM Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > At 11:21 PM 8/18/2015, you wrote: > > The battery contactor pulls nearly a full amp. Also it is very easy to > shed unneeded load by shutting=C3=82 the main down and going with the "E " bus. > > > Z-12 doesn't give you the option of running > with the battery contactor open . . . Z13-8 > DID offer that mode . . . due to the limited > output from the SD-8. Of course, it also offers > a calculated plan-c for operating battery > only. > > I once offered a Z-13/20 utilizing the > SD-20 . . . kinda messy and I pulled it. > I might do some asphalt-cogitation on another > pass at it. In the mean time, Z-12 is > exemplary of architectures flying on hundreds > of TC aircraft of the production lines of > Beech, Mooney, Piper et. als. . . . except > their 'e-bus' is an (ugh!!) 'avionics-bus'. > > > Bob . . . > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > ________________________________________________________________________________
Date: Aug 19, 2015
Subject: Re: electrical system master contactor
From: Bill Allen <billallensworld(at)gmail.com>
Good points well made. On 19 August 2015 at 17:26, Justin Jones wrote : > Electrically there is no reason a manual contactor would not work. The > master contractor will go dead and shut the battery off from the rest of > the system if the control voltage is cut off (such as a crash). The > mechanical switch may not. > > Access is the other consideration. If the battery is on the forward side > of the firewall you have 2 options. Put it close to the pilot or close to > the battery. Neither choice is good. If you put it near the pilot, you ha ve > a good amount of rather large gauge wire left unprotected. If you put it > near the battery, you may not have immediate access to it if you need it. > You may be able to connect a lever or cable to the switch that can bring > control into the cockpit but that adds weight, complexity, and another > component susceptible to failure. > > The solution I came up with is the solid state master relay from Waytek > Wire. > > http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/ > > It draws .125ma of current and is good for 300A continuous. Also rated at > 500A for 1 second. > > It is comparable in weight to a legacy master contactor, and it's heat > sink is made from aluminum. > > The battery charges perfectly through the relay and I have encountered > zero issues with it. It's about twice the cost of a quality legacy > contactor, with a rating of millions of cycles. Cutting edge technology. > > Justin > > On Aug 19, 2015, at 11:28, Bill Allen wrote: > > Hi, > > The master contactor pulls about 1.5 amps which is more than many > components that "work for their living" > > Is there any reason why a heavy duty manual contactor could not be used > instead of the traditional solenoid contactor, like this; > > http://tinyurl.com/nupw5xu > > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > On 19 August 2015 at 15:00, Robert L. Nuckolls, III < > nuckolls.bob(at)aeroelectric.com> wrote: > >> At 11:21 PM 8/18/2015, you wrote: >> >> The battery contactor pulls nearly a full amp. Also it is very easy to >> shed unneeded load by shutting=C3=82 the main down and going with the " E" bus. >> >> >> Z-12 doesn't give you the option of running >> with the battery contactor open . . . Z13-8 >> DID offer that mode . . . due to the limited >> output from the SD-8. Of course, it also offers >> a calculated plan-c for operating battery >> only. >> >> I once offered a Z-13/20 utilizing the >> SD-20 . . . kinda messy and I pulled it. >> I might do some asphalt-cogitation on another >> pass at it. In the mean time, Z-12 is >> exemplary of architectures flying on hundreds >> of TC aircraft of the production lines of >> Beech, Mooney, Piper et. als. . . . except >> their 'e-bus' is an (ugh!!) 'avionics-bus'. >> >> >> Bob . . . >> >> * >> >> ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-L ist <http://www.matronics.com/Navigator?AeroElectric-List> >> tp://forums.matronics.com <http://forums.matronics.com> >> _blank">http://www.matronics.com/contribution >> >> * >> >> > > > -- > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > * > > D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D > lectric-List"">http://www.matronics.com/Navigator?AeroElectric-List > D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D > //forums.matronics.com <http://forums.matronics.com> > D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D > ot;">http://www.matronics.com/contribution > D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D > > * > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- Bill Allen LongEz160 N99BA FD51 CZ4 G-BYLZ EGBJ ________________________________________________________________________________
Subject: Re: electrical system planning
From: "Jump4way" <andydelk(at)gmail.com>
Date: Aug 19, 2015
I'm planning a similar setup to what the original poster has mentioned. I too am trying to decide which Z diagram is better to follow. I have decided on a dual alternator and single battery setup. I have calculated my EBUS at 13.5 amps and my Battery Bus at 3.5 amps. I don't feel the 8amp dynamo would put out quite the current to meet my need although I understand not everything on the list would be used continuously so actual usuage would be closer to the 8 amps, I just seem to feel more comfortable with a little more margin. My question is if I were to use the 20amp alternator, or 30amp from planepower, which Z diagram would fit this better? The Z12M or Z13/8? Looking at the Z12, the alternator seems to tie in to the cold side of the battery master so if you want to load shed by shutting off the battery master, you will also shut off alternator power to the EBUS. Is the intent to never have to load shed with Z12 unless you were to suffer a rare dual alternator failure? I like the idea of the secondary alterator running in tandem with the primary alternator and picking up the load once bus voltage drops below 13.5 volts so the power transfer requires no user input. I'm undecided on all of the avionics that I'm going to install at this point but I'm fairly confident that the total continuous load will not exceed 20amps so the need to load shed is not likely. Is it worth designing the system for possible future growth and the need to load shed? If that is the case, would there be any reason I could not tie the 20amp standby alternator controlled with the SB!B-14 on the hot side of the battery contactor to give me the option of powering the EBUS with the master switch off? Are there any reliability considerations to take in to account that I'm not thinking of? Is the 8amp dynamo more reliable than the 20amp alternators or is it more of a weight and money thing? Sorry if I derailed the original posters thread. I appreciate any feedback you all might have to offer. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446165#446165 ________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: electrical system master contactor
>The solution I came up with is the solid state master relay from Waytek Wire. > ><http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/>http://www.waytekwire.com/item/44407/300A-Solid-State-Battery/ > > >It draws .125ma of current and is good for 300A continuous. Also >rated at 500A for 1 second. > >It is comparable in weight to a legacy master contactor, and it's >heat sink is made from aluminum. > >The battery charges perfectly through the relay and I have >encountered zero issues with it. It's about twice the cost of a >quality legacy contactor, with a rating of millions of cycles. >Cutting edge technology. Very few OBAM aircraft are fitted with a 'quality legacy contactor' purchased at a cost of $90. Similarly, while the C-140 was first fitted with the 6041H series 'quality contactor' it was eventually 'down-sized' to the beer-barrel contactors that were standard in tens of thousands of airplanes after that . . . and that was just at Cessna. Production Cessnas use the beer-barrel contactors to this very day. In my former life, there were opportunities to put in an official change proposal. Were I proposing to replace a beer-barrel contactor on a current production TC or STC aircraft with any form of 'upgrade' . . . I would be expected to present compelling case. An argument to convince the holders of purse-strings that the change would (1) reduce demonstrable risk or (2) reduce cost- of-ownership with the subject airframe. Most OBAM aircraft builders do not have access to "the numbers" that put orders of magnitude on either risk or cost-of-ownership for comparative analysis. At the same time, they are personally bombarded with ads, legends, anecdotes and interesting comparisons of why you want to fly product A as opposed to product B. Indeed, many suppliers leaning over the counters at OSH and buying big ads in S.A. or Kitplanes are engaged in an activity to 'trade' their particular offering for an acceptable quantity of your cash. In every free-market exchange, BOTH parties walk away thinking they got the 'better deal'. BOTH gave something they valued less for something they valued more. In the case before us, we want to consider the operational or risk value for replacing a $20 contactor with a $180 contactor. Should you walk away from a booth at OSH with a $180 contactor, what arguments might convince you that there was a positive return on investment for having made the purchase? Exactly what are the cost-of-ownership expectations for the swap? Is there a demonstrated lowering of risk? Is there not a lot of history for this style of part used as battery contactors on TC aircraft for 60+ years. Are there documented cases for failures of such devices placing an airplane/pilot in totally unmanageable. high risk situations? We are programmed as mere mortals to worry . . . sometimes about the wrong things and with risk of making decisions that don't do much for REAL risk. That's why we preach the doctrine of FMEA here on the List . . . it's exceedingly difficult and/or expensive to PURCHASE system reliability as opposed to BUILDING system reliability based on demonstrable risk and cost-of-ownership. I just received an email from EarthX citing their compliance with the wishes/requirements in battery performance from an ENGINE manufacturer. No doubt, recommendations from Rotax will offer powerful inducements for Rotax owners to be compliant with the manufacturer's wishes. They're also looking at upgrades for 'dual battery management systems' and 'serial data communications with an EFIS system'. This ol' TC born and bred graybeard would REALLY like to see the economics/risks arguments for those change proposals! The questions to be asked and answered go to real cost of ownership combined with effects on risk for incorporating hardware for which you have little understanding. no chance of repairing yourself and a expanded sense of helplessness when the little red light comes on. I have a car that throws fault codes which, more often than not, stay cleared after a reset. On two occasions, the codes were good and I fixed some things. But now I carry an OBDII code reader around in the car just to make sure that any given light is worthy of attention . . . I think maybe it's better than my 6-cyl, stick shift Chevys . . . the jury is still out. Bob . . . ________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: electrical system planning
At 04:37 PM 8/19/2015, you wrote: I'm planning a similar setup to what the original poster has mentioned. I too am trying to decide which Z diagram is better to follow. I have decided on a dual alternator and single battery setup. I have calculated my EBUS at 13.5 amps and my Battery Bus at 3.5 amps. I don't feel the 8amp dynamo would put out quite the current to meet my need although I understand not everything on the list would be used continuously so actual usuage would be closer to the 8 amps, I just seem to feel more comfortable with a little more margin. "margin"????? With a 17A minimum running load and an 8A standby alternator, you have NO margin. My question is if I were to use the 20amp alternator, or 30amp from planepower, which Z diagram would fit this better? The Z12M or Z13/8? Check with B&C . . . I think their larger spline drive alternators are good for more than 20A. Z-13/8 was NEVER intended to power an airplane with a total running load greater than 8-10A and the configuration was crafted to reduce running loads by the 0.7A contactor coil . . . Z-13/8 is not an option for you. Looking at the Z12, the alternator seems to tie in to the cold side of the battery master so if you want to load shed by shutting off the battery master, you will also shut off alternator power to the EBUS. Is the intent to never have to load shed with Z12 unless you were to suffer a rare dual alternator failure? Yes . . . That's what is done in hundreds . . . perhaps over a thousand TC aircraft that run a variant of Z-12. I like the idea of the secondary alterator running in tandem with the primary alternator and picking up the load once bus voltage drops below 13.5 volts so the power transfer requires no user input. I'm undecided on all of the avionics that I'm going to install at this point but I'm fairly confident that the total continuous load will not exceed 20amps so the need to load shed is not likely. Is it worth designing the system for possible future growth and the need to load shed? Reducing loads is usually pretty easy . . . it's call and OFF switch. The SB-1 regulator flashes a light at you until you exploit a sufficient number off OFF switches to reduce total load below 20A. If that is the case, would there be any reason I could not tie the 20amp standby alternator controlled with the SB!B-14 on the hot side of the battery contactor to give me the option of powering the EBUS with the master switch off? Are there any reliability considerations to take in to account that I'm not thinking of? Is the 8amp dynamo more reliable than the 20amp alternators or is it more of a weight and money thing? Sorry if I derailed the original posters thread. I appreciate any feedback you all might have to offer. Read the notes that go with the Z-figures. The whole purpose of a standby alternator and e-bus is to maximize conservation of energy in the EN ROUTE mode of flight. How may electro-whizzies to you NEED to comfortably achieve the descent/approach waypoint? If you've turned a lot of stuff OFF . . . total loads en route loads below 8A, then you have all the battery's capacity in reserve for approach to landing when you turn everything on that's useful for comfortable termination of the flight. This is what the load analysis sheets are all about on the website. In the RARE instance that you DO need to conserve power, have a check-list driven plan-B to keep it from becoming an emergency. Odds are, you don't need much hardware to get you to the destination airport traffic area. Z-13/8 is probably suited to 99% of all OBAM aircraft flying if the owner/operator takes the time to craft and implement a minimal power en-route mode of energy consumption. The airplanes I've rented didn't have standby alternators or e-busses. Yet, loss of the alternator was not going to have me looking for the asphalt 5 miles away. Here's my "ebus" for TC aircraft. http://tinyurl.com/ok7sjzt I shut the whole electrical system down and leave it off until time to enter the traffic area. An e-bus running 13.5A is not an ENDURANCE BUS. My suggestion to you is assume Z-13/8 and then see if you can get total running loads below 8A . . . actually 10A can probably be supported without seriously discharging the battery. Bob . . . ________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Anything 'unique' about incorporating EarthX?
>With a B&C overvoltage protection module (nominal trip voltage of >16.2 volts), I could have voltage to the battery greater than the >BMS triiger voltage and have loss of battery power supply at the >same time I have no alternator electrical source! How so? At what voltage and how fast does the BMS bring the battery back on line? What leads you to believe that during the interval from onset of an ov condition, alternator shut down and BMS recovery . . . that the bus voltage will drop too low for too long to keep the fan running? Bob . . . ________________________________________________________________________________
Date: Aug 19, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: electrical system master contactor
At 10:28 AM 8/19/2015, you wrote: >Hi, > >The master contactor pulls about 1.5 amps which >is more than many components =C2 that "work for their living"=C2 Actually, the legacy beer-barrel contactors are not that power hungry. http://tinyurl.com/mpcgp3t http://tinyurl.com/k6bwdqo >Is there any reason why a heavy duty manual >contactor could not be used instead of the >traditional solenoid contactor, like this; . . . but if you can place such a switch where it is easily reached with SHORT connections to the battery, that's good too. Took dual instruction in a Tri-Pacer about 1961 that with manual switches for both the starter and battery. But battery was under the seat and wire runs short. Bob . . . ________________________________________________________________________________
From: Justin Jones <jmjones2000(at)mindspring.com>
Subject: Re: electrical system planning
Date: Aug 19, 2015
The Z13/8 with a B&C 410H vacuum-pad drive alternator (substituted for the SD8) is more than capable of running a Dual ECU EFII system indefinitely. The B&C 410H will power 13.5 amps without an issue, but I am guessing the actual draw would be less than 13.5 Amps. =46rom what I have read here, it seems that most people overestimate the amperage that their =9Celectric whizzies=9D actually draw. Some folks tend to use the peak draw as the number for each of the items. Often peak draw is not sustained for the entire operation and should therefore not be used as the continuous operation number. Best to measure each device=99s amp draw prior to system planning and implementation. With a primary alternator and a backup alternator that is capable of running the required loads, you have effectively reduced the chances of a negative outcome due to electrical system exhaustion by a very large margin (greatly reduced risk). The chances of a dual alternator failure is very slim. If you know the actual draw of your system (running on the Ebus), you can experience a dual alternator failure, have the right procedures in place, and still know the amount of time you have until your propeller will stop pulling you. (Dependent on your battery=99s size and health) Id rather have 2 alternators and a single battery than a single alternator and 2 batteries. An appropriately sized backup alternator will easily outlast 2 batteries, and is much lighter to boot. Justin > On Aug 19, 2015, at 6:44 PM, Robert L. Nuckolls, III wrote: > > At 04:37 PM 8/19/2015, you wrote: > > I'm planning a similar setup to what the original poster has mentioned. I too am trying to decide which Z diagram is better to follow. I have decided on a dual alternator and single battery setup. > > I have calculated my EBUS at 13.5 amps and my Battery Bus at 3.5 amps. I don't feel the 8amp dynamo would put out quite the current to meet my need although I understand not everything on the list would be used continuously so actual usuage would be closer to the 8 amps, I just seem to feel more comfortable with a little more margin. > > "margin"????? With a 17A minimum running load > and an 8A standby alternator, you have NO margin. > > My question is if I were to use the 20amp alternator, or 30amp from planepower, which Z diagram would fit this better? The Z12M or Z13/8? > > Check with B&C . . . I think their larger spline > drive alternators are good for more than 20A. > > Z-13/8 was NEVER intended to power an airplane with > a total running load greater than 8-10A and the > configuration was crafted to reduce running loads by > the 0.7A contactor coil . . . Z-13/8 is not an > option for you. > > Looking at the Z12, the alternator seems to tie in to the cold side of the battery master so if you want to load shed by shutting off the battery master, you will also shut off alternator power to the EBUS. Is the intent to never have to load shed with Z12 unless you were to suffer a rare dual alternator failure? > > Yes . . . That's what is done in hundreds . . . > perhaps over a thousand TC aircraft that run > a variant of Z-12. > > > I like the idea of the secondary alterator running in tandem with the primary alternator and picking up the load once bus voltage drops below 13.5 volts so the power transfer requires no user input. > > I'm undecided on all of the avionics that I'm going to install at this point but I'm fairly confident that the total continuous load will not exceed 20amps so the need to load shed is not likely. Is it worth designing the system for possible future growth and the need to load shed? > > Reducing loads is usually pretty easy . . . it's > call and OFF switch. The SB-1 regulator flashes > a light at you until you exploit a sufficient number > off OFF switches to reduce total load below 20A. > > If that is the case, would there be any reason I could not tie the 20amp standby alternator controlled with the SB!B-14 on the hot side of the battery contactor to give me the option of powering the EBUS with the master switch off? > > Are there any reliability considerations to take in to account that I'm not thinking of? Is the 8amp dynamo more reliable than the 20amp alternators or is it more of a weight and money thing? > > Sorry if I derailed the original posters thread. I appreciate any feedback you all might have to offer. > > Read the notes that go with the Z-figures. The whole > purpose of a standby alternator and e-bus is to maximize > conservation of energy in the EN ROUTE mode of flight. > How may electro-whizzies to you NEED to comfortably > achieve the descent/approach waypoint? > > If you've turned a lot of stuff OFF . . . total loads > en route loads below 8A, then you have all > the battery's capacity in reserve for approach to > landing when you turn everything on that's useful for > comfortable termination of the flight. > > This is what the load analysis sheets are all about > on the website. In the RARE instance that you DO > need to conserve power, have a check-list driven > plan-B to keep it from becoming an emergency. Odds > are, you don't need much hardware to get you to the > destination airport traffic area. > > Z-13/8 is probably suited to 99% of all OBAM aircraft > flying if the owner/operator takes the time to > craft and implement a minimal power en-route mode > of energy consumption. > > The airplanes I've rented didn't have standby alternators > or e-busses. Yet, loss of the alternator was not going to > have me looking for the asphalt 5 miles away. Here's > my "ebus" for TC aircraft. > > http://tinyurl.com/ok7sjzt > > <http://tinyurl.com/ok7sjzt> I shut the whole electrical system down and leave it > off until time to enter the traffic area. > > An e-bus running 13.5A is not an ENDURANCE BUS. > My suggestion to you is assume Z-13/8 and then see > if you can get total running loads below 8A . . . > actually 10A can probably be supported without seriously > discharging the battery. > > Bob . . . > > > <http://www.matronics.com/Navigator?AeroElectric-List> <http://www.matronics.com/contribution> > ________________________________________________________________________________
Date: Aug 20, 2015
Subject: Re: electrical system master contactor
From: Bob Verwey <bob.verwey(at)gmail.com>
Thats the route i have gone On Wednesday, August 19, 2015, Bill Allen wrote : > Hi, > > The master contactor pulls about 1.5 amps which is more than many > components that "work for their living" > > Is there any reason why a heavy duty manual contactor could not be used > instead of the traditional solenoid contactor, like this; > > http://tinyurl.com/nupw5xu > > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > On 19 August 2015 at 15:00, Robert L. Nuckolls, III < > nuckolls.bob(at)aeroelectric.com > > wrote: > >> At 11:21 PM 8/18/2015, you wrote: >> >> The battery contactor pulls nearly a full amp. Also it is very easy to >> shed unneeded load by shutting=C3=82 the main down and going with the " E" bus. >> >> >> Z-12 doesn't give you the option of running >> with the battery contactor open . . . Z13-8 >> DID offer that mode . . . due to the limited >> output from the SD-8. Of course, it also offers >> a calculated plan-c for operating battery >> only. >> >> I once offered a Z-13/20 utilizing the >> SD-20 . . . kinda messy and I pulled it. >> I might do some asphalt-cogitation on another >> pass at it. In the mean time, Z-12 is >> exemplary of architectures flying on hundreds >> of TC aircraft of the production lines of >> Beech, Mooney, Piper et. als. . . . except >> their 'e-bus' is an (ugh!!) 'avionics-bus'. >> >> >> Bob . . . >> >> * >> >> ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-L ist <http://www.matronics.com/Navigator?AeroElectric-List> >> tp://forums.matronics.com <http://forums.matronics.com> >> _blank">http://www.matronics.com/contribution >> >> * >> >> > > > -- > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- Best... Bob Verwey ________________________________________________________________________________
Subject: Re: electrical system master contactor
From: Bill Putney <billp(at)wwpc.com>
Date: Aug 20, 2015
It depends on where your battery is. The Master Contractor should be really close to the battery. The wire between the battery and the Master has no protection and if that wire gets shorted there is nothing you can do about it in flight. It will draw as much current as the battery can supply and turn that into heat, read fire. If you have your battery on the other side of the firewall and you use something like a marine battery disconnect switch in the engine compartment next to the battery you could extend the switch shaft into the cockpit and put the knob where you can reach it. Another option would be to rig a lever on a marine cutoff switch and use a cable pull control in the cockpit to control the switch. Remember that the Master has to be capable of passing engine starting current through it. That's probably the heaviest load you have in the aircraft. Whatever you use has to be rated to at least the current of the starter (when stalled) and anything else that is on during startup. The switch you choose should also be designed to cut off high currents under load. If you have a master bus short you want to be able cut off the battery circuit without the switch exploding from the plasma generated when it opens. That's why I suggested a marine battery cutoff switch. It's a manual switch designed for the purpose. Bill On 8/19/15 22:35, Bob Verwey wrote: > Thats the route i have gone > > On Wednesday, August 19, 2015, Bill Allen > wrote: > > Hi, > > The master contactor pulls about 1.5 amps which is more than many > components that "work for their living" > > Is there any reason why a heavy duty manual contactor could not be > used instead of the traditional solenoid contactor, like this; > > http://tinyurl.com/nupw5xu > > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > On 19 August 2015 at 15:00, Robert L. Nuckolls, III > > > wrote: > > At 11:21 PM 8/18/2015, you wrote: > >> The battery contactor pulls nearly a full amp. Also it is >> very easy to shed unneeded load by shutting the main down >> and going with the "E" bus. > > Z-12 doesn't give you the option of running > with the battery contactor open . . . Z13-8 > DID offer that mode . . . due to the limited > output from the SD-8. Of course, it also offers > a calculated plan-c for operating battery > only. > > I once offered a Z-13/20 utilizing the > SD-20 . . . kinda messy and I pulled it. > I might do some asphalt-cogitation on another > pass at it. In the mean time, Z-12 is > exemplary of architectures flying on hundreds > of TC aircraft of the production lines of > Beech, Mooney, Piper et. als. . . . except > their 'e-bus' is an (ugh!!) 'avionics-bus'. > > > Bob . . . > > *ist" > target="_blank">http://www.matronics.com/Navigator?AeroElectric-List > tp://forums.matronics.com <http://forums.matronics.com> > _blank">http://www.matronics.com/contribution * > > > -- > Bill Allen > LongEz160 N99BA FD51 > CZ4 G-BYLZ EGBJ > > *ist" > target="_blank">http://www.matronics.com/Navigator?AeroElectric-List > tp://forums.matronics.com > _blank">http://www.matronics.com/contribution * > > > -- > Best... > Bob Verwey > > > http://www.matronics.com/contribution ________________________________________________________________________________
Date: Aug 20, 2015
Subject: Re: electrical system master contactor
From: Bob Verwey <bob.verwey(at)gmail.com>
Hey Bill, I have the marine type and its about 1ft from the battery which sits under the pilot seat. On Thursday, August 20, 2015, Bill Putney wrote: > It depends on where your battery is. The Master Contractor should be > really close to the battery. The wire between the battery and the Master > has no protection and if that wire gets shorted there is nothing you can do > about it in flight. It will draw as much current as the battery can suppl y > and turn that into heat, read fire. > > If you have your battery on the other side of the firewall and you use > something like a marine battery disconnect switch in the engine compartme nt > next to the battery you could extend the switch shaft into the cockpit an d > put the knob where you can reach it. Another option would be to rig a lev er > on a marine cutoff switch and use a cable pull control in the cockpit to > control the switch. > > Remember that the Master has to be capable of passing > engine starting current through it. That's probably the heaviest load you > have in the aircraft. Whatever you use has to be rated to at least the > current of the starter (when stalled) and anything else that is on during > startup. The switch you choose should also be designed to cut off high > currents under load. If you have a master bus short you want to be able c ut > off the battery circuit without the switch exploding from the plasma > generated when it opens. That's why I suggested a marine battery cutoff > switch. It's a manual switch designed for the purpose. > > Bill > > On 8/19/15 22:35, Bob Verwey wrote: > > Thats the route i have gone > > On Wednesday, August 19, 2015, Bill Allen < > > billallensworld(at)gmail.com > > wrote: > >> Hi, >> >> The master contactor pulls about 1.5 amps which is more than many >> components that "work for their living" >> >> Is there any reason why a heavy duty manual contactor could not be used >> instead of the traditional solenoid contactor, like this; >> >> http://tinyurl.com/nupw5xu >> >> Bill Allen >> LongEz160 N99BA FD51 >> CZ4 G-BYLZ EGBJ >> >> On 19 August 2015 at 15:00, Robert L. Nuckolls, III < >> nuckolls.bob(at)aeroelectric.com >> > wrote: >> >>> At 11:21 PM 8/18/2015, you wrote: >>> >>> The battery contactor pulls nearly a full amp. Also it is very easy to >>> shed unneeded load by shutting=C3=82 the main down and going with the "E" bus. >>> >>> >>> Z-12 doesn't give you the option of running >>> with the battery contactor open . . . Z13-8 >>> DID offer that mode . . . due to the limited >>> output from the SD-8. Of course, it also offers >>> a calculated plan-c for operating battery >>> only. >>> >>> I once offered a Z-13/20 utilizing the >>> SD-20 . . . kinda messy and I pulled it. >>> I might do some asphalt-cogitation on another >>> pass at it. In the mean time, Z-12 is >>> exemplary of architectures flying on hundreds >>> of TC aircraft of the production lines of >>> Beech, Mooney, Piper et. als. . . . except >>> their 'e-bus' is an (ugh!!) 'avionics-bus'. >>> >>> >>> Bob . . . >>> >>> * >>> >>> ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric- List <http://www.matronics.com/Navigator?AeroElectric-List> >>> tp://forums.matronics.com <http://forums.matronics.com> >>> _blank">http://www.matronics.com/contribution >>> >>> * >>> >>> >> >> >> -- >> Bill Allen >> LongEz160 N99BA FD51 >> CZ4 G-BYLZ EGBJ >> >> * >> >> ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-L ist <http://www.matronics.com/Navigator?AeroElectric-List> >> tp://forums.matronics.com <http://forums.matronics.com> >> _blank">http://www.matronics.com/contribution >> >> * >> >> > > -- > Best... > Bob Verwey > > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- Best... Bob Verwey ________________________________________________________________________________
From: Efraim Otero Leongomez <efraim.otero(at)gmail.com>
Subject: Building a buss bar for my wood and fabric biplane
Date: Aug 20, 2015
Dear All: I have purchased and read Bob Nuckolls Aeroelectics book. I am a newbie in this matter and want to instal an electrical system on my plane. It is a fisher Celbrity powered by a Continental O200. I bought a B&C Specialety BCh433 alternator which I plan to instal and get enough power generation to charge my battery and power a Sandia STX transponder and a flightline Fl760 Comms radio. How do I go about constructing the Buss bar to hook my avionics up? I purchased some brass sheet bars but do not have a clue as to how to mount them, drill them and attach them to the firewall. Any ideas? Pictures? Suggestions? Thank you in advance for your input! Cheers Ephraim ________________________________________________________________________________
Date: Aug 20, 2015
Subject: Re: Building a buss bar for my wood and fabric biplane
From: don van santen <donvansanten(at)gmail.com>
B and C fuse holders make great "bus" bars. On Aug 20, 2015 12:31 PM, "Efraim Otero Leongomez" wrote: > efraim.otero(at)gmail.com> > > Dear All: > I have purchased and read Bob Nuckoll=99s Aeroelectics book. I am a newbie > in this matter and want to instal an electrical system on my plane. It is a > fisher Celbrity powered by a Continental O200. > > I bought a B&C Specialety BCh433 alternator which I plan to instal and ge t > enough power generation to charge my battery and power a Sandia STX > transponder and a flightline Fl760 Comms radio. > > How do I go about constructing the Buss bar to hook my =9Cavionics =9D up? I > purchased some brass sheet bars but do not have a clue as to how to mount > them, drill them and attach them to the firewall. > > Any ideas? Pictures? Suggestions? > > Thank you in advance for your input! > Cheers > Ephraim > =========== =========== =========== =========== > > ________________________________________________________________________________
Subject: Re: electrical system planning
From: "Jump4way" <andydelk(at)gmail.com>
Date: Aug 20, 2015
Thanks for the replies. I'll get to work seeing if there is a way to reduce the EBUS load to something more manageable. Like original poster, If I reduce down to only the items essential to keep the engine running, I'll be at 10amps so that alone says that the SD8 alternator is not my best option. I also need to get a handle on the total load required for each of the busses. If I can keep that under the 20-30 amps that the backup alternators can provide then the decisions seem more simplified. [/quote]I once offered a Z-13/20 utilizing the SD-20 . . . kinda messy and I pulled it. I might do some asphalt-cogitation on another pass at it.[/quote] I would certainly be interested to see a Z-13/20 if you get the time to put it together. I like the idea of being able to load shed items by simply closing off the master switch. It seems what I'm learning from reading these forums and Bob's book that I could put items essential for flght (EFII primary coil, ECU 88, and primary fuel pump) on the battery bus. The decisions come on what additional items to put on the EBUS. I think the EBUS could be used as a place to power the additional items that help assure a safe outcome of the flight such as GPS for nagivation, One Comm, autopilot servos and EFIS. All of the other items could be on the main buss such as Flaps, landing and nav lights, trim motors, transponder, 12V outlet, USB charging, Cabin lights, and secondary EFII Coil pump and ECU). This plan would allow quickly load shedding everything on the main buss in the event of a dual alternator failure. I think Z12 will allow this. Does this plan sound reasonable or am I approaching this from the wrong angle? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446207#446207 ________________________________________________________________________________
Subject: Re: Building a buss bar for my wood and fabric biplane
From: Kent or Jackie Ashton <kjashton(at)vnet.net>
Date: Aug 20, 2015
The cheapest and easiest way, IMO, is to use a Cooper Bussman fuse block for ATC blade fuses. Power comes to the block, then through the fuses to the various systems. Many versions here http://www.cooperindustries.com/content/public/en/bussmann/transportation/products/power_distribution/fuse_panels.html When I have wanted an essential bus, I take the fuse block apart, cut the large center conductor, solder on an extra mounting tab on the other end of it, and get two buses out of it. You can mount them on the panel or out-of-the-way. -Kent > On Aug 20, 2015, at 3:23 PM, Efraim Otero Leongomez wrote: > > > Dear All: > I have purchased and read Bob Nuckolls Aeroelectics book. I am a newbie in this matter and want to instal an electrical system on my plane. It is a fisher Celbrity powered by a Continental O200. > > I bought a B&C Specialety BCh433 alternator which I plan to instal and get enough power generation to charge my battery and power a Sandia STX transponder and a flightline Fl760 Comms radio. > > How do I go about constructing the Buss bar to hook my avionics up? I purchased some brass sheet bars but do not have a clue as to how to mount them, drill them and attach them to the firewall. > > Any ideas? Pictures? Suggestions? > > Thank you in advance for your input! > Cheers > Ephraim > > > > ________________________________________________________________________________
Subject: Re: Building a buss bar for my wood and fabric biplane
From: "user9253" <fransew(at)gmail.com>
Date: Aug 20, 2015
A fuse block will be less expensive and might be easier to install. The type sold by B&C has the output terminals on the front, but they can be bent backwards somewhat. It is not designed to be mounted on the instrument panel, although it could be with some ingenuity. http://www.bandc.biz/fuseholder12-slot.aspx http://home.earthlink.net/~dswartzendruber/id13.html The Bussman SERIES 15710 Looks like it is intended to be panel mounted. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446209#446209 ________________________________________________________________________________
Date: Aug 21, 2015
Subject: Master disconnect
From: Janet Amtmann <jgamtmann2(at)gmail.com>
On the subject of "Master Disconnect" or Master Switch: If a manual switch is desired, Waytechwire has a selection of disconnect switches rated at hundreds of Amps. used in commercial vehicles. I use one in my Airstream to disconnect the battery in case of emergency (battery is mounted between tow vehicle and trailer and heavy wiring in trailer). I had considered mounting a manual switch in the RV6, next to the battery with a shaft extension to the dash. Simple, reliable etc. Jurgen Amtmann http://www.waytekwire.com/item/44080/Heavy-Duty-Battery-Master/ ________________________________________________________________________________
Subject: Re: Anything 'unique' about incorporating EarthX?
From: "blues750" <den_beaulieu(at)yahoo.com>
Date: Aug 22, 2015
[quote="nuckolls.bob(at)aeroelect"] > With a B&C overvoltage protection module (nominal trip voltage of 16.2 volts), I could have voltage to the battery greater than the BMS triiger voltage and have loss of battery power supply at the same time I have no alternator electrical source! How so? At what voltage and how fast does the BMS bring the battery back on line? What leads you to believe that during the interval from onset of an ov condition, alternator shut down and BMS recovery . . . that the bus voltage will drop too low for too long to keep the fan running? Bob . . . > [b] Bob, That's part of my dilemma, I cannot answer that question yet. Failure characteristics with respect to time onset and voltage ouptut during a failure to an overvoltage output by a generator or regulator of my type I do not know. If I am recalling correctly, I have read that the B&C OVPM reacts within milliseconds to an overvoltage issue. The Earthx BMS starts doing it's thing around 15.5 volts - but that is dependent on a few variables. I have asked the engineer for some time, temp, charge state and charging voltage correlations to try and determine how quickly the BMS will react and protect the cells and simultaneously deprive me of needed power to my busses from the battery. Again, it is my understanding after talking with the engineer at Earthx, that no voltage is available from the battery (nothing allowed in or out) while the BMS is protecting the battery I still need to followup with those questions, if they are indeed the right questions to be asking! (I think so [Rolling Eyes] ) but was trying to get more insight here first. Based on my understanding at this point, I am concerned about a scenario in which the output from the alt and R/R to my battery and busses is somehow slowly rising above 15-16 volts. The BMS decides to act out and take my batteries offline. I can fly on the alternator if necessary though maybe not ideal for some equipment or to what value the voltage may rise. But to get my batteries back, I do need to alleviate the overvoltage presented to them. Ideally, I would notice the overvoltage prior to the BMS getting protective, simply shut down the alternator and proceed to the hangar with my batteries supplying the required voltage as intended. But, having to take my alternator off-line with my batteries off-line simultaneously does not seem like proper design if that is indeed a real possibility. Appreciate the initial feedback and comments, would gladly welcome any more related to this scenario. Dave Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446282#446282 ________________________________________________________________________________
Subject: Re: Newbie with PM alternator feed question
From: "blues750" <den_beaulieu(at)yahoo.com>
Date: Aug 22, 2015
[quote="nuckolls.bob(at)aeroelect"] > > (1) Is dynamo current "self limiting" a characteristic of all 3 phase PM type alternators? (dynamos?) Would gladly eliminate those three 20 amp c/b's if not required! the PM alternators will self-destruct if presented with a hard short on their windings generated by failure of the rectifier=regulator. Use in-line fuses. One for the single phase machines, two for the three phase machines. These need no be crew- accessible. Do you mean these "need to be" or "need not be" crew accessible? Why? or why not? > (2) Was planning on a 40A ANL type fuse for the 10 ga wire from the relay to the primary bus. What is the rated output of your altenrator? An inline maxi-fuse of next-step higher value would be fine and a lot less bulky. 30 Amp alternator, and I like the idea of the inline maxi-fuse versus the ANL because of the reduced size. I thought ANL type was preferred because of the longer response time and thus helped to avoid potential nuisance trips? Bob . . . > [b] Thanks Bob! A real treat to be able to discuss topics with subject matter experts! My cluebag continues to fill... Dave Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446283#446283 ________________________________________________________________________________
Date: Aug 23, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Newbie with PM alternator feed question
At 09:24 PM 8/22/2015, you wrote: [quote="nuckolls.bob(at)aeroelect"] > > (1) Is dynamo current "self limiting" a characteristic of all 3 phase PM type alternators? (dynamos?) Would gladly eliminate those three 20 amp c/b's if not required! the PM alternators will self-destruct if presented with a hard short on their windings generated by failure of the rectifier=regulator. Use in-line fuses. One for the single phase machines, two for the three phase machines. These need no be crew- accessible. Do you mean these "need to be" or "need not be" crew accessible? Why? or why not? Do the Failure Mode Effects Analysis: What kind of failure would put these windings at risk? What is the probability that system functionality will be restored by resetting crew accessible circuit protection after suffering such a failure? Suggest you review the Fuses vs. Breakers discussions on the website . . . http://tinyurl.com/nmwyak5 . . . I think there's a pretty good case to be made for having NO crew accessible circuit protection for a constellation of reasons including. (1) Likelihood of restoring functionality after any righteous trip is zero. The fuse blew because something was broke . . . (2) Unlike the circuit protection in the TC aircraft, any discovery of a nuisance-trip condition in an OBAM aircraft can be quickly FIXED . . . (3) Crew accessible circuit protection has little up-side. It takes up panel space and it's a potential distraction from being pilot- in-the-air and saving mechanic-on-the-ground activities for later. (4) Paying homage to the federally mandated prohibition for unreachable protection of 'critical' hardware calls for doing your FMEA and making minimizing single-systems critical to comfortable termination of flight. In cases where this is simply not possible . . . like a one and only-one fuel injection system, then that system needs to be crafted with critical-item reliability like propeller bolts . . . ten to the minus bazillion failures per flight hour. Then, having its breaker/fuse accessible in the cockpit becomes immaterial. > (2) Was planning on a 40A ANL type fuse for the 10 ga wire from the relay to the primary bus. ANL's and their cousins are members of the genus "current limiter" . . . exceedingly robust and designed to protect fat-feeders from battery-fed, 1000A+ style faults. There are few instances in our size airplanes where the ANL-type devices are really well placed. The vast majority of protection goals are handily met with fast-fuses sized to avoid nuisance trips. I prefer the ANL-style device for automotive-style alternator b-leads because of their bolt-on style mounting and wire-termination that makes them a bit more convenient than any of the fuse holders but a well-considered fuse installation is never a 'bad' idea. What is the rated output of your altenrator? An inline maxi-fuse of next-step higher value would be fine and a lot less bulky. 30 Amp alternator, and I like the idea of the inline maxi-fuse versus the ANL because of the reduced size. I thought ANL type was preferred because of the longer response time and thus helped to avoid potential nuisance trips? It's true that current limiters simply do not nuisance trip but in this case, the maxi-fuse seems the more elegant solution. Thanks Bob! A real treat to be able to discuss topics with subject matter experts! My cluebag continues to fill... You're most welcome my friend . . . ________________________________________________________________________________
Subject: Re: Bending copper (bus) bar
From: "JOHN TIPTON" <jmtipton(at)btopenworld.com>
Date: Aug 23, 2015
The copper bar is 2mm (0.08inch) - so bend cold over a not too sharp (vice) edge Thanks Bob (and all) John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446290#446290 ________________________________________________________________________________
From: Ed Meyer <ed.meyer(at)outlook.com>
Subject: Re: Anything 'unique' about incorporating EarthX?
Date: Aug 24, 2015
"With a B&C overvoltage protection module (nominal trip voltage of 16.2 vo lts), I could have voltage to the battery greater than the BMS triiger volt age and have loss of battery power supply at the same time I have no altern ator electrical source!" I just talked with Kathy at EarthX and mentioned this concern with the OV protection. I am very near making the decision on batteries to use on my project also using the B and C regulator so was very interested in thi s. She strongly recommended to use one of the new aircraft specific battery designs, ETX680, ETX900, or ETX1200, and that these batteries have the OV protection set at over 19V in order to address this very issue. She sai d new batteries also have greater redundancy and battery fault warning than their other batteries. Ed ________________________________________________________________________________
Date: Aug 25, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Anything 'unique' about incorporating EarthX?
At 01:00 PM 8/24/2015, you wrote: > "With a B&C overvoltage protection module (nominal trip voltage of > 16.2 volts), I could have voltage to the battery greater than the > BMS triiger voltage and have loss of battery power supply at the > same time I have no alternator electrical source!" > > I just talked with Kathy at EarthX and mentioned this concern > with the OV protection. I am very near making the decision on > batteries to use on my project also using the B and C regulator > so was very interested in this. She strongly recommended to use one > of the new aircraft specific battery designs, ETX680, ETX900, > or ETX1200, and that these batteries have the OV protection set at > over 19V in order to address this very issue. She said new > batteries also have greater redundancy and battery fault > warning than their other batteries. 19 volts? Hmmm . . . wonder how they arrived at that figure . . . which seems to argue with some widely circulated 'never exceed' numbers that are reputed to trash the battery. It will be interesting to see how the return on investment shakes out for this new direction in battery technologies. When you're selling Apple products, there's a market segment that can be depended on to 'need' whatever new features are offered. That market is a classic demonstration of "Build it and they will come". A market with little incentive to deduce what features really improve performance and/or reduce risk. Speaking of great experiments in "Build it an they will come", there are many thousands of housing and commercial units built and supposedly move-in ready. Multiple complete cities standing empty in another part of the world . . . Emacs! . . . again, a powerful demonstration that encourage folks to understand the economics . . . the return on investment for needs versus wants. I am still mystified as to how it's a 'good thing' to add a wad of transistors to a battery just to achieve a few pounds of weight savings . . . we'll just have to wait and see. Bob . . . ________________________________________________________________________________
Date: Aug 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Request for some direction and advise
At 03:17 PM 8/29/2015, you wrote: Bob, I apologize for writing you directly but I am at my wits end with this problem. Not a problem except that we should do this on the List . . . there are individuals who are able and willing to contribute to the study/solution, many more who would benefit from reading the exchanges . . .. First let me tell you that I have a GNS430W and a TruTrack Digiflight II VSVG autopilot along with the Dynon 10A and Dynon HS34 module to connect the Dynon to the GNS430W. I have always had a problem with the radio developing a lot of static on certain frequencies to the extent that I could not make out what was being said. Not always, but mostly I would get this very loud ShShShShSh! On frequencies like 121.1 which is approach for the Orlando area. Since I have now moved to the Dallas area, the problem has changed to a much worse condition. Now when I key the mike, I sometimes get the autopilot kicking off, sometimes the radio kicks off, and the last couple of flights, the electrically dependent engine will all but die while I have the mike key depressed. I am not finished with living, so I have to find and fix this before I fly again. This sounds like two separate problems. What kind of airplane and where is the comm antenna installed? I have no real knowledge of electrical things, but I used to think that I could follow directions and connect wires. I am beginning to think I may have been wrong about that! I can not think of anything that would cause this phenomenon when the mike is keyed. Hopefully you can come up with some direction that I can follow to discover a cause. I have come to think that somehow I must be getting a voltage on this ground line that is then feeding back to all the equipment in the plane. The thing is, I really don't have any clue about how I would go about testing for such a thing even if that turns out to be the problem. Let's get all the data before we begin picking at straws . . . What I hope is that something in this problem will strike a pattern to you that will allow you to give me a direction to look for the problem. If it does, I would need some pretty explicit directions as to what and how to test whatever you think would make sense to test. I know this is rambling and non-specific, but if you should need any more info, I will be happy to try and provide it. Thanks for all the help you have given all of us in the past and hopefully you can come up with a little assistance for me here. Not a problem, its what we do here. But at the same time, know that diagnostics by e-mail are fraught with risk for lack of understanding and forcing unnecessary delays. Are there no builders and/or radio cognizant acquaintances local to you that could participate in this activity? I suspect that the root cause is simple . . . it usually is. Have you physically checked the antenna coax from the back of the radio to the antenna? Unhook the coax, tug on the connectors at both ends. See if they can be 'twisted' on the wire. Their attachment should be quite robust 5=10 pounds of pull or twisting with the fingers should produce NO motion between connector and coax. The noise is, I believe, a separate issue. Have you attempted to locate potential antagonists? Pull all breakers/fuses except for those necessary to run the radio and engine. Does the noise go away? Thank you, Bill Bob . . . ________________________________________________________________________________
Date: Aug 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: RE: Request for some direction and advise
At 11:32 AM 8/30/2015, you wrote: I appreciate any assistance I can get. A difficult to hear some transmissions is one thing but with the engine now involved, that is a major problem. Yeah . . . that tends to get your attention . . . I will try and answer your questions in order. This is a Lancair Legacy. Fiberglass not carbon fiber, although some components are carbon fiber. No carbon fiber near the radio or antenna installation. The comm. Antenna is a Advanced Electronics antenna as is described here http://www.aircraftspruce.com/catalog/avpages/antennasystems.php The antenna is installed on the right side if the fuselage, inside just behind the rear luggage bulkhead. The antenna is long enough that it forms the shape of a "C" on the right side of the fuselage. It extends from about the center line on the top to the center line on the bottom. The bottom end of the antenna is very close, within an inch, of one of the rudder cables. The rudder cable does not connect to a ground due to the plane being fiberglass. What are the chronological and service ages of this installation. I.e. how long has the airplane been flying and how many hours in that time. Noises aside, I presume that the comm radio has performed satisfactorily until now? I just moved to the airport at Mesquite, TX on Friday. I have been on their waiting list for 20 months. There is no radio shop on the field and I have not yet met any builders there. Unless they are related, I hope to find and fix the kicking off of the autopilot and radio and the shutting down of the engine before the static. They are almost certainly unrelated. Noises in receivers at selected frequencies have little or nothing in common with energy from your transmitter getting into places it doesn't belong. The later symptom screams of broken coax shield connection. Energy from your transmitter is supposed to be 'piped' to the antenna . . . generally away from potential victims before being gracefully launched into the ether. should your coax shield become ungrounded, PARTICULARLY at the radio end, the entire coax becomes a very disorderly antenna that radiates stuff in and around the cockpit with energy that might prove deleterious to performance of the various systems. This is a relatively rare condition but made a greater risk in OBAM aviation where appliances are NOT generally tested for immunity to strong RF . . . a thing we do religiously in TC aircraft. But even WITH proper homage paid at the altar of the EMI gods, ALL systems have a limit as to how much mischievous energy can be ignored. The fact that you have TWO affected systems suggests that the energy levels involved are large and almost certainly associated with loss of integrity in that 'pipe' . . . the antenna feed line. I will check the coax connectors to make certain that they are tight. Are there any scenarios that come to mind where the keying of the mike could cause other equipment to shut down? They are probably manifestations arising from a single cause. Does this sound like voltage is being introduced onto the ground system? Does it sound like a short somewhere? Surely the radio, coax, antenna could not be putting out radiation that would shut down the other equipment??? Under the WRONG condition cited above, the coax is no longer a coax . . . and it easily joins turns the best behaved transmitter into a cockpit thug. Other than the coax connectors, where would you look first? Second? If we had my toolbox there, I'd first dummy load the transmitter and note that the effect goes away. I'd also put the antenna analyzer on your comm antenna coax to confirm the cockpit thug hypothesis. After that, it's pretty much touchy-feely activities to deduce from whence the pipe is leaking. Bob . . . ________________________________________________________________________________
Date: Aug 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: RE: Request for some direction and advise
At 01:14 PM 8/30/2015, you wrote: >I bought the radio and other electronics along about 2005. The FAA >deemed the plane airworthy in Dec of 2010. yeahhh . . . but . . . > I now have 110 hours on it. The radio has always been a little > squirrelly. I previously had problems > with the autopilot dropping out but not shutting off. The > TruTrak folks suggested I install a connector > that has capacitors in it. That seemed to help for a while. that was advice from TruTrak? to change the connector on THEIR product? Given the technological roots of this company I am . . . shall we say . . . mystified? > Last year I had an instance where I could not hear ATC but they > could hear me. Not caused by the hiss, but just dead air. I > managed to find another controller that I could hear and he relayed > what they were trying to tell me. I also can not pick up any ATIS > until within 20 miles from any station that I have tried and I > think that is supposed to be closer to 50 miles. Clearly, not all is right with your antenna system (presuming the radio is okay) . . . inability to hear you is consistent with a severe transmission line problem or perhaps even a broke antenna. How hard would it be to remove your antenna for bench testing? > >Several years ago, a friend checked the SWR on the antenna from the >COAX connector at the radio and it was less than 2 at the time. I >don't remember the exact number but it was low. Normally, low SWR is a good thing but you need to look at then antenna over its full range of intended operation. "SWR" instruments are not all necessarily golden either . . . I've pitched a couple of cheapies in the trash after discovering serious discrepancies in displayed readings versus physical realities. Bob . . . ________________________________________________________________________________
Date: Aug 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Opportunity alert
Speaking of antenna analyzers, one of my work-horses in the toolbox, the MFJ-259 is on sale right now for a rather attractive price. http://tinyurl.com/nke8w88 Not the top-dog analyzer by any means . . . it's not a Bird or a Fluke . . . but it's of exceptional value if you take care of it. I used to rent one out but physical effects of shipping and neophyte usage took a toll greater than the rental fees. Had to give it up and buy myself a new one. Take care of this puppy . . . works good . . . lasts a long time. EAA chapters ought to own one along with a designated operator to go around and sort out antenna problems for their membership. Just saying . . . Bob . . . ________________________________________________________________________________
From: Dennis Johnson <pinetownd(at)volcano.net>
Subject: Hydraulic Pump Start-Up Amperage
Date: Aug 30, 2015
My Lancair Legacy has a nominal 12 volt electrically powered hydraulic pump that raises and lowers the landing gear. When the airplane has sat in the hangar overnight, the hydraulic pressure bleeds down enough that the pump turns on momentarily when I turn on the master switch. Master relays aren =99t designed to make or break large electrical currents and I always wondered if I was damaging it by hitting it with the large surge current f rom the hydraulic pump turning on as the master relay closes. A friend has a fancy little electronic box that measures electrical current , sampling many, many times per second. Here is a trace of the current flo w through a shunt between the battery and master relay. The blue trace sho ws an 80 amp surge as the master relay closes and the hydraulic pump almost simultaneously turns on. In this case, with the airplane on jacks, I had the gear down and the landing gear selector switch in the =9Cup =9D position when I turned on the master switch. That means that as soon a s the master relay closed, the hydraulic pump also turned on to raise the g ear. The 80 amp surge lasts for about one or two milliseconds. About ten millis econds later, the hydraulic pump obviously starts and the current surges to 155 amps. Landing gear extension and retraction each take about six secon ds. In order to focus on the very brief surges, this graph shows only a fr action of the first second. The other two traces show the current draw from raising and lowering the la nding gear in the customary manner, after the master relay has already clos ed. Their two traces were overlayed with the first one. I=99m not sure what this means. However, years of trouble free opera tion for my airplane and many similar ones show that the master relay isn =99t damaged by the hydraulic pump turn on surge. Dennis Lancair Legacy, 860 hours ________________________________________________________________________________
From: <rnjcurtis(at)charter.net>
Subject: AeroElectric-List:_Hydraulic_Pump_Start-Up_Amperage?
Date: Aug 31, 2015
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Date: Aug 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Hydraulic Pump Start-Up Amperage
> >The other two traces show the current draw from >raising and lowering the landing gear in the >customary manner, after the master relay has >already closed. Their two traces were overlayed with the first one. > >I=99m not sure what this means. However, years >of trouble free operation for my airplane and >many similar ones show that the master relay >isn=99t damaged by the hydraulic pump turn on surge. Yup, that's what they do . . . and it's generally a good thing for battery master contactors NOT to make them close against a heavy load. The fact that you've not had a problem may be a classic demonstration of "who wins the relay race". There is a natural delay time between first voltage on a contactor to first -touch in the bounce then some more time until bouncing ceases. It is possible that your pump controls have sufficient energize delay time that they don't begin to electrically hammer the battery contactor until after it's reasonably stable. Its a function many variables that can make one configuration eat battery contactors while others are not so problematic. There are simple circuits you can put in series with the gear-down pump contactor to delay power to the coil by a few hundred milliseconds or so. Totally transparent to the system and crew but in SOME cases may have a profound benefit to battery contactor life. I did the sketch for a Glasair owner about 20 years ago . . . didn't hear from him again after he installed "The Mod". I'll dig it up for you if you're interested. Bob . . . ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advise
Date: Aug 30, 2015
I saw where someone else on the list a while back was discussing adding that connector to their TruTrak at the company's suggestion. It is supposed to keep RFI out as I recall. The antenna is glassed in and not removable, I tried to attach it with tape, but I could not get it to stay in place so I just glassed it in. I do have a second antenna that I could try if I don't find anything with the coax. I only have a Volt-Ohm meter so I don't think I could bench test the antenna. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Sunday, August 30, 2015 5:18 PM Subject: AeroElectric-List: RE: Request for some direction and advise At 01:14 PM 8/30/2015, you wrote: I bought the radio and other electronics along about 2005. The FAA deemed the plane airworthy in Dec of 2010. yeahhh . . . but . . . I now have 110 hours on it. The radio has always been a little squirrelly. I previously had problems with the autopilot dropping out but not shutting off. The TruTrak folks suggested I install a connector that has capacitors in it. That seemed to help for a while. that was advice from TruTrak? to change the connector on THEIR product? Given the technological roots of this company I am . . . shall we say . . . mystified? Last year I had an instance where I could not hear ATC but they could hear me. Not caused by the hiss, but just dead air. I managed to find another controller that I could hear and he relayed what they were trying to tell me. I also can not pick up any ATIS until within 20 miles from any station that I have tried and I think that is supposed to be closer to 50 miles. Clearly, not all is right with your antenna system (presuming the radio is okay) . . . inability to hear you is consistent with a severe transmission line problem or perhaps even a broke antenna. How hard would it be to remove your antenna for bench testing? Several years ago, a friend checked the SWR on the antenna from the COAX connector at the radio and it was less than 2 at the time. I don=12t remember the exact number but it was low. Normally, low SWR is a good thing but you need to look at then antenna over its full range of intended operation. "SWR" instruments are not all necessarily golden either . . . I've pitched a couple of cheapies in the trash after discovering serious discrepancies in displayed readings versus physical realities. Bob . . . ________________________________________________________________________________
Date: Aug 31, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: RE: Request for some direction and advise
At 10:15 PM 8/30/2015, you wrote: >I saw where someone else on the list a while back was discussing >adding that connector to their TruTrak at the company's >suggestion. It is supposed to keep RFI out as I recall. > >The antenna is glassed in and not removable, I tried to attach it >with tape, but I could not get it to stay in place so I just glassed >it in. I do have a second antenna that I could try if I don't find >anything with the coax. I only have a Volt-Ohm meter so I don't >think I could bench test the antenna. > I feel your 'pain' . . . more than once I have been presented with a conundrum with tools and test equipment out of reach. Do the touchy-feely things with the feed line first. Then consider building a test antenna. A simple dipole, fed at center with a length of coax fited with BNC cable-female to reach across the aircraft to the opposite side where you can tape it in place. See if the problem resolves. I don't know any specifics about the antenna you have installed. I have been made aware of several products like it wherein the manufacturer thought it a good idea to include a balun/matching transformer in that little potted box at the center. On such product could not handle the power from the transmitter and failed the balun after some hours in service. We're grasping at straws here but one of those straws IS the short one. Without useful diagnostic tools . . . it's the best we can do. But if it's any consolation, I've encountered ONLY ONE EMC problem on an airplane wherein root cause could NOT be resolved . . . only swapped out. Emacs! Seems that some really nifty technology advances in communications hardware were installed on an aircraft being manufactured to still adequate methods designed 40 years ago. A technology that placed NEW and exceedingly difficult requirements on the airframe. From that time to this day, the aircraft has suffered a host of EMC problems that occur at intervals, sometimes in small batches, and will never be resolved except that the old wire-type antennas be re-installed. I'm not suggesting that your situation is intractable . . . only that not all combinations of hardware are plug-n-play in all airframes and yours is fixable. Only spent a few hundred $K tracking the other one down . . . yours will be MUCH less expensive. Bob . . . ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advise
Date: Aug 31, 2015
I checked the connectors at the two ends of the com coax. They were both well connected to the shield and I couldn't pull them off the cable. The, I guess you would call it the barrel, of the connector at the radio end was a little difficult to twist after the connector was removed. I twisted it back and forth a little and it seemed to loosen up. I suppose there could have been some corrosion where it rotates, but I didn't see anything. I checked and found the radio backing plate had continuity with ground. There is a card edge connector that is used as a shield ground connector at the backing plate that seemed to me to be a loose fit. I mean it was easy to remove it from the plate it connects to. It is held in place by a couple of screws so there was no danger of it falling off, but it was a loose fit so I suppose that some of the pins could have not been making good contact. I don't know if any of the shields that are in this connector could have caused the problem. I wonder if I should try and bend the pins so that they make a tighter fit? Also should the edge it slips over be brightened up some? It is the same grey color as the backing plate? I found another RG-400 cable with connectors on both ends that I could use to hook up the other antenna I have to see if that helps. I don't know if the spare cable will reach to the existing antenna. If it does I could try that as well. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, August 31, 2015 10:40 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise At 10:15 PM 8/30/2015, you wrote: I saw where someone else on the list a while back was discussing adding that connector to their TruTrak at the company=12s suggestion. It is supposed to keep RFI out as I recall. The antenna is glassed in and not removable, I tried to attach it with tape, but I could not get it to stay in place so I just glassed it in. I do have a second antenna that I could try if I don=12t find anything with the coax. I only have a Volt-Ohm meter so I don=12t think I could bench test the antenna. I feel your 'pain' . . . more than once I have been presented with a conundrum with tools and test equipment out of reach. Do the touchy-feely things with the feed line first. Then consider building a test antenna. A simple dipole, fed at center with a length of coax fited with BNC cable-female to reach across the aircraft to the opposite side where you can tape it in place. See if the problem resolves. I don't know any specifics about the antenna you have installed. I have been made aware of several products like it wherein the manufacturer thought it a good idea to include a balun/matching transformer in that little potted box at the center. On such product could not handle the power from the transmitter and failed the balun after some hours in service. We're grasping at straws here but one of those straws IS the short one. Without useful diagnostic tools . . . it's the best we can do. But if it's any consolation, I've encountered ONLY ONE EMC problem on an airplane wherein root cause could NOT be resolved . . . only swapped out. Emacs! Seems that some really nifty technology advances in communications hardware were installed on an aircraft being manufactured to still adequate methods designed 40 years ago. A technology that placed NEW and exceedingly difficult requirements on the airframe. From that time to this day, the aircraft has suffered a host of EMC problems that occur at intervals, sometimes in small batches, and will never be resolved except that the old wire-type antennas be re-installed. I'm not suggesting that your situation is intractable . . . only that not all combinations of hardware are plug-n-play in all airframes and yours is fixable. Only spent a few hundred $K tracking the other one down . . . yours will be MUCH less expensive. Bob . . . ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advise
Date: Sep 01, 2015
One other thing that I just thought of that may be a factor. The backing plate through connectors that the radio slides into when it is inserted into the tray are very wobbly. It is very easy to make a circle with them that is at least 1/8 inch in radius. I have never thought about these connectors before because I thought that they were wobbly in order to line up with the radio when in is inserted. But now thinking about it, it seems to me that they should firm up when the radio is inserted because they are making rigid contact with the radio?? Mine are still wobbly after the radio is inserted. Could these connectors or the backing plate be somehow incorrectly installed? Does anyone know if these connectors should be firm after the radio is installed? Could this be where I have a bad connection with the shield? What about the other shield grounds described below? Would they be a factor if that card edge connector does not make a firm connection? There is a boss just to the side of this card edge connector that I am considering using to run a separate ground wire from the backing plate to the "forest of tabs" ground block. Are there any opinions on this idea? Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Bradburry Sent: Monday, August 31, 2015 8:51 PM Subject: RE: AeroElectric-List: RE: Request for some direction and advise I checked the connectors at the two ends of the com coax. They were both well connected to the shield and I couldn't pull them off the cable. The, I guess you would call it the barrel, of the connector at the radio end was a little difficult to twist after the connector was removed. I twisted it back and forth a little and it seemed to loosen up. I suppose there could have been some corrosion where it rotates, but I didn't see anything. I checked and found the radio backing plate had continuity with ground. There is a card edge connector that is used as a shield ground connector at the backing plate that seemed to me to be a loose fit. I mean it was easy to remove it from the plate it connects to. It is held in place by a couple of screws so there was no danger of it falling off, but it was a loose fit so I suppose that some of the pins could have not been making good contact. I don't know if any of the shields that are in this connector could have caused the problem. I wonder if I should try and bend the pins so that they make a tighter fit? Also should the edge it slips over be brightened up some? It is the same grey color as the backing plate? I found another RG-400 cable with connectors on both ends that I could use to hook up the other antenna I have to see if that helps. I don't know if the spare cable will reach to the existing antenna. If it does I could try that as well. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, August 31, 2015 10:40 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise At 10:15 PM 8/30/2015, you wrote: I saw where someone else on the list a while back was discussing adding that connector to their TruTrak at the company=12s suggestion. It is supposed to keep RFI out as I recall. The antenna is glassed in and not removable, I tried to attach it with tape, but I could not get it to stay in place so I just glassed it in. I do have a second antenna that I could try if I don=12t find anything with the coax. I only have a Volt-Ohm meter so I don=12t think I could bench test the antenna. I feel your 'pain' . . . more than once I have been presented with a conundrum with tools and test equipment out of reach. Do the touchy-feely things with the feed line first. Then consider building a test antenna. A simple dipole, fed at center with a length of coax fited with BNC cable-female to reach across the aircraft to the opposite side where you can tape it in place. See if the problem resolves. I don't know any specifics about the antenna you have installed. I have been made aware of several products like it wherein the manufacturer thought it a good idea to include a balun/matching transformer in that little potted box at the center. On such product could not handle the power from the transmitter and failed the balun after some hours in service. We're grasping at straws here but one of those straws IS the short one. Without useful diagnostic tools . . . it's the best we can do. But if it's any consolation, I've encountered ONLY ONE EMC problem on an airplane wherein root cause could NOT be resolved . . . only swapped out. Emacs! Seems that some really nifty technology advances in communications hardware were installed on an aircraft being manufactured to still adequate methods designed 40 years ago. A technology that placed NEW and exceedingly difficult requirements on the airframe. From that time to this day, the aircraft has suffered a host of EMC problems that occur at intervals, sometimes in small batches, and will never be resolved except that the old wire-type antennas be re-installed. I'm not suggesting that your situation is intractable . . . only that not all combinations of hardware are plug-n-play in all airframes and yours is fixable. Only spent a few hundred $K tracking the other one down . . . yours will be MUCH less expensive. Bob . . . ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advise
Date: Sep 01, 2015
I just spoke with Garmin field support. Pretty nice guy when you finally get through to him. He had a radio in front of him. He said that while he could move the through connectors with the radio installed, they were not very loose, pretty firm. Also the card edge connector came off pretty easily after the two screws were removed, similar to mine. I plan to remove the radio and backing plate and connect them outside of the tray to see if a better connection to the backing plate helps the problem. I also plan to raise the card edge contacts a little to help make a better connection there as well. If the better connection to the backing plate works, I will have to determine why the connection is not sufficient when the radio is in the tray. Are there any suggestions, or comments? Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Bradburry Sent: Tuesday, September 01, 2015 10:34 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise One other thing that I just thought of that may be a factor. The backing plate through connectors that the radio slides into when it is inserted into the tray are very wobbly. It is very easy to make a circle with them that is at least 1/8 inch in radius. I have never thought about these connectors before because I thought that they were wobbly in order to line up with the radio when in is inserted. But now thinking about it, it seems to me that they should firm up when the radio is inserted because they are making rigid contact with the radio?? Mine are still wobbly after the radio is inserted. Could these connectors or the backing plate be somehow incorrectly installed? Does anyone know if these connectors should be firm after the radio is installed? Could this be where I have a bad connection with the shield? What about the other shield grounds described below? Would they be a factor if that card edge connector does not make a firm connection? There is a boss just to the side of this card edge connector that I am considering using to run a separate ground wire from the backing plate to the "forest of tabs" ground block. Are there any opinions on this idea? Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Bradburry Sent: Monday, August 31, 2015 8:51 PM Subject: RE: AeroElectric-List: RE: Request for some direction and advise I checked the connectors at the two ends of the com coax. They were both well connected to the shield and I couldn't pull them off the cable. The, I guess you would call it the barrel, of the connector at the radio end was a little difficult to twist after the connector was removed. I twisted it back and forth a little and it seemed to loosen up. I suppose there could have been some corrosion where it rotates, but I didn't see anything. I checked and found the radio backing plate had continuity with ground. There is a card edge connector that is used as a shield ground connector at the backing plate that seemed to me to be a loose fit. I mean it was easy to remove it from the plate it connects to. It is held in place by a couple of screws so there was no danger of it falling off, but it was a loose fit so I suppose that some of the pins could have not been making good contact. I don't know if any of the shields that are in this connector could have caused the problem. I wonder if I should try and bend the pins so that they make a tighter fit? Also should the edge it slips over be brightened up some? It is the same grey color as the backing plate? I found another RG-400 cable with connectors on both ends that I could use to hook up the other antenna I have to see if that helps. I don't know if the spare cable will reach to the existing antenna. If it does I could try that as well. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, August 31, 2015 10:40 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise At 10:15 PM 8/30/2015, you wrote: I saw where someone else on the list a while back was discussing adding that connector to their TruTrak at the company=12s suggestion. It is supposed to keep RFI out as I recall. The antenna is glassed in and not removable, I tried to attach it with tape, but I could not get it to stay in place so I just glassed it in. I do have a second antenna that I could try if I don=12t find anything with the coax. I only have a Volt-Ohm meter so I don=12t think I could bench test the antenna. I feel your 'pain' . . . more than once I have been presented with a conundrum with tools and test equipment out of reach. Do the touchy-feely things with the feed line first. Then consider building a test antenna. A simple dipole, fed at center with a length of coax fited with BNC cable-female to reach across the aircraft to the opposite side where you can tape it in place. See if the problem resolves. I don't know any specifics about the antenna you have installed. I have been made aware of several products like it wherein the manufacturer thought it a good idea to include a balun/matching transformer in that little potted box at the center. On such product could not handle the power from the transmitter and failed the balun after some hours in service. We're grasping at straws here but one of those straws IS the short one. Without useful diagnostic tools . . . it's the best we can do. But if it's any consolation, I've encountered ONLY ONE EMC problem on an airplane wherein root cause could NOT be resolved . . . only swapped out. Emacs! Seems that some really nifty technology advances in communications hardware were installed on an aircraft being manufactured to still adequate methods designed 40 years ago. A technology that placed NEW and exceedingly difficult requirements on the airframe. From that time to this day, the aircraft has suffered a host of EMC problems that occur at intervals, sometimes in small batches, and will never be resolved except that the old wire-type antennas be re-installed. I'm not suggesting that your situation is intractable . . . only that not all combinations of hardware are plug-n-play in all airframes and yours is fixable. Only spent a few hundred $K tracking the other one down . . . yours will be MUCH less expensive. Bob . . . ________________________________________________________________________________
From: "Andy Elliott" <a.s.elliott(at)cox.net>
Subject: Wiring portable transceiver through audio panel?
Date: Sep 01, 2015
The wood/fiberglass aircraft I bought has a single NAV-COM (KX-155A) and a single embedded comm antenna. It also has an 2002-vintage PS Engineering PMA-7000B audio panel. I would like to add another comm radio to the aircraft and was considering something like the Yaesu FTA-550. This radio has provision for a headset connector and for 10=B10.5V power input. I was wondering if it is possible to splice the headset connections from the portable into the audio panel as COM2, and get =93normal=94 comm radio functionality, specifically 1. Can the mike output from the audio panel drive the portable? 2. Can the stick mounted PTT, through the audio panel, key the portable? 3. Can the portable headset output be used as input to the audio panel? 4. What might be a recommended way to get the 10V feed for the portable? And if it is possible, what kind of special connections/modifications might need to be made? Thanks, Andy ------------------------ Andy Elliott, CL:480-695-9568 N729LS, GP-4 ________________________________________________________________________________
Subject: Re: Wiring portable transceiver through audio panel?
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 01, 2015
On 9/1/2015 1:39 PM, Andy Elliott wrote: > > The wood/fiberglass aircraft I bought has a single NAV-COM (KX-155A) > and a single embedded comm antenna. It also has an 2002-vintage PS > Engineering PMA-7000B audio panel. I would like to add another comm > radio to the aircraft and was considering something like the Yaesu > FTA-550. This radio has provision for a headset connector and for > 100.5V power input. > > I was wondering if it is possible to splice the headset connections > from the portable into the audio panel as COM2, and get normal comm > radio functionality, specifically > > 1.Can the mike output from the audio panel drive the portable? > The portable should accept any typical aviation mic level input (assuming it has mic/PTT/headset jacks). Normally, an audio panel 'feeds through' the mic signal to the transmitter selected by the audio panel's transmit selector switch. So, yes. > > 2.Can the stick mounted PTT, through the audio panel, key the portable? > Assuming that the portable has 'standard' headset and mic/PTT jacks (either full size or miniature), then any external PTT should key the portable. (Transmit select switch should route PTT in addition to mic signal to the correct radio.) > > 3.Can the portable headset output be used as input to the audio panel? > Should be the same level & impedance range as any other radio's headset output, so, yes. > > 4.What might be a recommended way to get the 10V feed for the portable? > Check with the mfgr 1st; it's possible that the radio will accept a typical 14v input from the a/c power buss. If it won't, then the mfgr should have a 14V-10V adapter to power the radio from ship's power. > > And if it is possible, what kind of special connections/modifications > might need to be made? > If it's a typical aviation handheld transceiver, all you should need is plugs/wiring to connect the mic, PTT, headset, and power jacks to the audio panel's ins/outs and to the ship's power buss. > > Thanks, > > Andy > > ------------------------ > > Andy Elliott, CL:480-695-9568 > > N729LS, GP-4 > > Charlie ________________________________________________________________________________
Subject: Re: Request for some direction and advise
From: "Eric M. Jones" <emjones(at)charter.net>
Date: Sep 02, 2015
My Father (who worked on Westinghouse's part of the USN Vanguard rocket), related to me the ultimate failure with it: Test techs would unplug all the tubes (yes it had tubes) test the tubes and stick them back into their sockets....time after time after time. (One thinks they must also have unplugged every module too). So everything tested fine, and when the rocket took off, all the vibration caused the tube sockets to quit making contact because they were worn out. Whether or not this was entirely true, the lesson remains: Contacts are the first place to look for most sorts of electrical problems. For the remainder, contacts probably had something to do with the failure in the first place. Contact failure can occur in ways you would never suspect. In the medical field people get shocked because the plating has worn off brass contacts, which now behave as diodes. The HF used in surgery ("Bovies") now generates HV DC instead of the HF AC used in electrosurgery. OUCH! So always suspect connections first. Both intended and unintended. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446683#446683 ________________________________________________________________________________
Date: Sep 02, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: RE: Request for some direction and advise
>One other thing that I just thought of that may be a factor. The >backing plate through connectors that the radio slides into when it >is inserted into the tray are very wobbly. It is very easy to make >a circle with them that is at least 1/8 inch in radius. I have >never thought about these connectors before because I thought that >they were wobbly in order to line up with the radio when in is >inserted. But now thinking about it, it seems to me that they >should firm up when the radio is inserted because they are making >rigid contact with the radio?? Mine are still wobbly after the >radio is inserted. Could these connectors or the backing plate be >somehow incorrectly installed? Tray connectors often 'float' on the tray itself so as to accommodate dimenational differences between tray and radio as the radio is slid into the tray. Similarly, your antenna connectors a the back of the radio may appear 'loose' in spite of having perfect electrical integrity. http://tinyurl.com/qa5hr7l In the image sited above, we see where electrical integrity is achieved as a separate component of mechanical mounting. A BNC connector attached to an appliance. http://tinyurl.com/pmy4hsg In the video above, we see that a connector is "loose" to move in some regard while mantaining electrical integrity of the connection. > >Does anyone know if these connectors should be firm after the radio >is installed? Could this be where I have a bad connection with the shield? The connections I am most concerned about are between the coax shield and it's terminating connector. > >What about the other shield grounds described below? Would they be >a factor if that card edge connector does not make a firm >connection? There is a boss just to the side of this card edge >connector that I am considering using to run a separate ground wire >from the backing plate to the "forest of tabs" ground block. Are >there any opinions on this idea? Your symptoms scream of antagonistic disruption of TWO different systems that suggest a problem with the level of RF in the cockpit due to an antenna system problem . . . not with the radio's power/signal wires. Bob . . . ________________________________________________________________________________
From: "Don Johnson" <donjohnson(at)northernneck.com>
Subject: Tesla Meter App and Magnetism
Date: Sep 02, 2015
About a year ago when flying my RV-9A to Air Venture, I noticed after departing a small airport in Ohio and preparing to fly over Lake Michigan, that my vertical card compass was stuck on 230 degrees. I used the GPS heading to reorient my DG and went on my way=85 Upon returning home, I decided to replace that compass with one mounted on the center support to the roll bar. Same problem ' stuck on 230 degrees + or ' 10 degrees. Now in the middle of upgrading from steam gauges to Dynon 180, etc., I ran across an Iphone App called Tesla Meter on the App store. There are at least 10 similar apps that point to a source of magnetism and give a strength reading in a measurement referred to as =B5T. Moving it around the cockpit, the signal was very strong and pointed to the junction of the roll bar and fuselage ' readings of approximately 500 =B5T on the both the left and right junctions of the fuselage and the roll bar. The remainder of the roll bar and the support showed readings of 60 to 70 =B5T. While I was at it, I checked other steel pieces around the plane and found two bars on the motor mount with readings in the 400+ =B5T range. Knowing this group is far more informed than I am, I pose the following questions: 1. Is the high reading at the mounting points of the roll bar the likely cause of the stuck compass? 2. Can you offer an explanation as the why those areas show a high reading? 3. If those areas are the problem, how do I correct it? Thanks for your help. Don Johnson RV-9A ________________________________________________________________________________
Subject: Re: Tesla Meter App and Magnetism
From: "user9253" <fransew(at)gmail.com>
Date: Sep 02, 2015
I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. Here is a youtube movie about making a demagnetizer: https://www.youtube.com/watch?v=8kKTJQTyX-w Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446707#446707 ________________________________________________________________________________
Subject: Re: Tesla Meter App and Magnetism
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 02, 2015
On 9/2/2015 7:41 PM, user9253 wrote: > > I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. > If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. > Here is a youtube movie about making a demagnetizer: > https://www.youtube.com/watch?v=8kKTJQTyX-w > Joe > > -------- > Joe Gores Find a TV repair shop that's been around since before flat screens (tube type days). Ask if they still have their degaussing coil (mine's still packed away somewhere, after closing the shop 20 years ago). ________________________________________________________________________________
Subject: Re: Tesla Meter App and Magnetism
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 02, 2015
On 9/2/2015 7:41 PM, user9253 wrote: > > I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. > If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. > Here is a youtube movie about making a demagnetizer: > https://www.youtube.com/watch?v=8kKTJQTyX-w > Joe > > -------- > Joe Gores > > Add to my previous post: don't forget to remove the compass & anything else that might get trashed by a big magnetic field (AHARS units, magnetometers, etc). ________________________________________________________________________________
Subject: Re: Tesla Meter App and Magnetism
From: "user9253" <fransew(at)gmail.com>
Date: Sep 02, 2015
Found this on the internet about demagnetizing: > What if you could put many wraps of insulated wire around the pipe and connect an AC welder to the wire. The longer the wire the better and of course the wire will have to handle the amps you feed it with the welder. Move the coil of wire down the length of the pipe. Don't see why this wouldn't work. LOL George -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446710#446710 ________________________________________________________________________________
Date: Sep 02, 2015
From: Tim Olson <Tim(at)MyRV10.com>
Subject: Re: Tesla Meter App and Magnetism
I would suggest also posting to the RV list. I don't know a lot about it but a few years ago I read many posts regarding degaussing canopy frames. I think the people built their own degaussers even, perhaps. I guess a lot of the RV's with metal frames had some residual magnetism and people would degauss them and get them back to much less magnetic. Also, maybe try searching the matronics archive via the web login. Tim On 9/2/2015 7:41 PM, user9253 wrote: > > I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. > If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. > Here is a youtube movie about making a demagnetizer: > https://www.youtube.com/watch?v=8kKTJQTyX-w > Joe > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=446707#446707 > ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advise
Date: Sep 02, 2015
Bob, Success! I thank you for sending me in the proper direction to find this problem. I would never have figured out that it was RF loose in the cockpit. While I was checking for where I could possibly have a loose connection this afternoon, I removed the radio from the tray and measured both the length of the radio and the distance it had to reach to the connectors in the back plate. Whoops! Looks like the radio needs to be seated deeper into the tray! Stupid builder tricks! When I installed the radio, I installed a bezel around them and to make it look nicer, I put the bezel under the faceplate on the radio. The radio passed the test Garmin has for that, (three turns of the screw after the radio powers on) but apparently over time it got looser and looser and started having more and more symptoms. I modified the bezel this afternoon so the radio would properly seat and the problem appears to have resolved. I was getting a huge RF leak from the back of the radio prior to it getting into the coax. I am completing my conditional inspection so it will be a few days before I can fly and see just what symptoms I have fixed. Thanks, Bob! Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Wednesday, September 02, 2015 12:53 PM Subject: RE: AeroElectric-List: RE: Request for some direction and advise One other thing that I just thought of that may be a factor. The backing plate through connectors that the radio slides into when it is inserted into the tray are very wobbly. It is very easy to make a circle with them that is at least 1/8 inch in radius. I have never thought about these connectors before because I thought that they were wobbly in order to line up with the radio when in is inserted. But now thinking about it, it seems to me that they should firm up when the radio is inserted because they are making rigid contact with the radio?? Mine are still wobbly after the radio is inserted. Could these connectors or the backing plate be somehow incorrectly installed? Tray connectors often 'float' on the tray itself so as to accommodate dimenational differences between tray and radio as the radio is slid into the tray. Similarly, your antenna connectors a the back of the radio may appear 'loose' in spite of having perfect electrical integrity. http://tinyurl.com/qa5hr7l In the image sited above, we see where electrical integrity is achieved as a separate component of mechanical mounting. A BNC connector attached to an appliance. http://tinyurl.com/pmy4hsg In the video above, we see that a connector is "loose" to move in some regard while mantaining electrical integrity of the connection. Does anyone know if these connectors should be firm after the radio is installed? Could this be where I have a bad connection with the shield? The connections I am most concerned about are between the coax shield and it's terminating connector. What about the other shield grounds described below? Would they be a factor if that card edge connector does not make a firm connection? There is a boss just to the side of this card edge connector that I am considering using to run a separate ground wire from the backing plate to the =13forest of tabs=14 ground block. Are there any opinions on this idea? Your symptoms scream of antagonistic disruption of TWO different systems that suggest a problem with the level of RF in the cockpit due to an antenna system problem . . . not with the radio's power/signal wires. Bob . . . ________________________________________________________________________________
From: "Jim Kale" <jimkale(at)roadrunner.com>
Subject: Re: Tesla Meter App and Magnetism
Date: Sep 02, 2015
Way back when TVs had large Picture Tubes, more properly called cathode ray tubes, technicians had coils of wire plugged into 110 volt AC. They waved them all over the television metal chassis. This alternating magnetic field demagnetized the TV. Also called degaussing. Magnetic fields on the TV Chassis would distort the picture. This system could also be used on the metal parts of an airplane. However, if you don't know what you are doing, you could easily demagnetize some parts that need their magnetic fields to operate properly. Yes, like the compass, but possibly also some delicate and expensive avionics. Let the experimenter beware!! -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Charlie England Sent: Wednesday, September 2, 2015 8:45 PM Subject: Re: AeroElectric-List: Re: Tesla Meter App and Magnetism --> On 9/2/2015 7:41 PM, user9253 wrote: > --> > > I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. > If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. > Here is a youtube movie about making a demagnetizer: > https://www.youtube.com/watch?v=8kKTJQTyX-w > Joe > > -------- > Joe Gores Find a TV repair shop that's been around since before flat screens (tube type days). Ask if they still have their degaussing coil (mine's still packed away somewhere, after closing the shop 20 years ago). ________________________________________________________________________________
Subject: Re: Tesla Meter App and Magnetism
From: "racerjerry" <gnking2(at)verizon.net>
Date: Sep 03, 2015
Electric welding on steel often leaves residual magnetism problems. Yes, the solution is an AC powered degaussing coil. Yes, remove your instruments and radios beforehand. Or forget the whole thing and move your compass to a location where it is less affected. Google how to make a degaussing coil. Careful, most coils get HOT rather quickly. Besides burning your fingers, the coils can melt their wire insulation, burn and cause a short circuit. Most degaussing coils will self-destruct if left powered on too long. Power your coil from a GFCI protected circuit - or mount a household GFCI in an outlet box with a line cord (your own GFCI protected extension cord). SLOWLY move the degaussing coil in a circular motion all around the affected area. While the coil is still energized, slowly move the coil away from the steel. You MUST SLOWLY move the energized coil AWAY from the affected area. Remember that the degaussing coil IS an electromagnet (without a core) and you can magnetize (make it worse or change magnetic polarity) just as easily as demagnetize. . Test for excessive magnetic attraction using a handheld compass. Repeat degaussing steps as necessary. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446724#446724 ________________________________________________________________________________
From: RGent1224(at)aol.com
Date: Sep 03, 2015
Subject: Re: Tesla Meter App and Magnetism
In the olden days we used to take a piece of wire that just fit in place of the heating element and the length we needed to do the job for that purpose. Worked good Dick In a message dated 9/3/2015 8:55:08 A.M. Central Daylight Time, fransew(at)gmail.com writes: --> AeroElectric-List message posted by: "user9253" I have not actually tried this but a knowledgeable person told me that a soldering gun (NOT iron) can be used to demagnetize steel. The object to be demagnetized is passed through the soldering gun heating element loop while the gun trigger is pulled. Of course an airframe is too big, but maybe the soldering gun heating element can be removed from the gun, then placed around the steel tube, then connected back onto the soldering gun. Then the soldering gun trigger is pulled while moving the gun back and forth along the steel tube. If that is not feasible, then maybe someone else knows how to make a demagnetizer using the same principle. Here is a youtube movie about making a demagnetizer: https://www.youtube.com/watch?v=8kKTJQTyX-w Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446707#446707 ________________________________________________________________________________
From: "Les Goldner" <lgold@quantum-associates.com>
Subject: Electric engine noise problem
Date: Sep 03, 2015
Bob, I built a small electric motor glider that has a 30+KW DC motor. The motor controller sends electric pulses to the motor at various frequencies to control the motor. The batteries put out about 100 volts and at times 250-amps are going through the controller to the motor. The batteries and controller are not grounded to the frame to prevent potential catastrophic shorts since the lithium pack would put out thousands of amps if shorted. My problem is that these pulses cause extreme radio noise on my hand-held ICOM radio and I cannot hear any communications. Is there an easy fix for this issue? Regards, Les ________________________________________________________________________________
Date: Sep 03, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: RE: Request for some direction and advise
At 11:27 PM 9/2/2015, you wrote: Bob, Success! I thank you for sending me in the proper direction to find this problem. I would never have figured out that it was RF loose in the cockpit. While I was checking for where I could possibly have a loose connection this afternoon, I removed the radio from the tray and measured both the length of the radio and the distance it had to reach to the connectors in the back plate. Whoops! Looks like the radio needs to be seated deeper into the tray! Stupid builder tricks! When I installed the radio, I installed a bezel around them and to make it look nicer, I put the bezel under the faceplate on the radio. The radio passed the test Garmin has for that, (three turns of the screw after the radio powers on) but apparently over time it got looser and looser and started having more and more symptoms. I modified the bezel this afternoon so the radio would properly seat and the problem appears to have resolved. I was getting a huge RF leak from the back of the radio prior to it getting into the coax. I am completing my conditional inspection so it will be a few days before I can fly and see just what symptoms I have fixed. Sounds like the project is moving forward again. Great! Let us know what you discover. As I recall, we still have a receiving noise issue that MIGHT be related to the antenna connector . . . but probably not. We can tackle that one after you've had more time to assess the state of your universe. Bob . . . ________________________________________________________________________________
Date: Sep 03, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Electric engine noise problem
At 09:54 AM 9/3/2015, you wrote: >Bob, >I built a small electric motor glider that has a 30+KW DC motor. The >motor controller sends electric pulses to the motor at various >frequencies to control the motor. The batteries put out about 100 >volts and at times 250-amps are going through the controller to the >motor. The batteries and controller are not grounded to the frame to >prevent potential catastrophic shorts since the lithium pack would >put out thousands of amps if shorted. >My problem is that these pulses cause extreme radio noise on my >hand-held ICOM radio and I cannot hear any communications. Is there >an easy fix for this issue? >Regards, >Les Probably not. Your project is perhaps the most profound demonstration for why we do a LOT of testing to agreed-upon limits before putting hardware in the airplane. Pulse width modulated controllers from heated seats to blowers to flap systems have offered some challenging situations to designers . . . mostly having to do with RF tight packaging backed up with good filters at the enclosure wall. The last 150+ amps flap controller I had any contact with had about a killobux worth of rather expensive capacitors in a filter array on an etched circuit board. Lacking details on your particular suite of hardware, I'm unable to be more specific. Perhaps pictures, schematics and data on your purchased hardware will lend more insight for offering advice. Bob . . . ________________________________________________________________________________
Date: Sep 03, 2015
Subject: Degaussing tools
From: Janet Amtmann <jgamtmann2(at)gmail.com>
As a watch repairer many years ago I bought a degausser to demagnetize watch tweezers. Nothing like a hairspring hanging on to the tweezers and not letting go. It is (I still have it) a coil of wire around a 3" dia. plastic tube with a zip cord and 115VAC plug on the end and a momentary push button switch. Put the tool into the coil, push the button and slowly withdraw the tool. Voila, no more captive hairsprings. If you release the button with the tool in the coil, depending on the part of the cycle that you released the switch, you may have made a real magnet out of your miniature screw driver. That's the reason for withdrawing the tool slowly, then releasing the switch. Jurgen Amtmann (RV-6A) ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advice
Date: Sep 03, 2015
Ok, I will report after I know more of what I have fixed..I am wildly optimistic at this point! I did check the coax connector at the antenna and it seemed solid. I really have no way to check the potted box at the antenna, but I do have a spare antenna just like it that I could try if necessary. I also have a piece of RG-400 about 10 ft long with connectors on both ends that I can try with both antennas. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, September 03, 2015 10:06 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise At 11:27 PM 9/2/2015, you wrote: Sounds like the project is moving forward again. Great! Let us know what you discover. As I recall, we still have a receiving noise issue that MIGHT be related to the antenna connector . . . but probably not. We can tackle that one after you've had more time to assess the state of your universe. Bob . . . ________________________________________________________________________________
From: "David Lloyd" <skywagon(at)charter.net>
Subject: Re: RE: Request for some direction and advise
Date: Sep 03, 2015
Some Garmin 430 users (maybe others) have had problems with their comm side suddenly go on the fritz. If the the chassis "tray" is not mounted with its forward lip aligned with the panel front edge or, better, a tad forward of the panel front face, it can loose connections in the rear connection sockets. Many times these chassis are mounted without this fact in mind and are bolted in slightly to the rear. The 430 bezel stops the unit from being pushed fully into this ill mounted chassis. It is also important to use your thumbs to mount the 430 into the chassis and using the chassis locking screw to only complete what your thumbs do to get the 430 fully engaged in the rear connections. Don't force the 430 in using only the chassis locking screw adjuster. D ------------------------------------------------------------------------- ------- ----- Original Message ----- From: Bill Bradburry To: aeroelectric-list(at)matronics.com Sent: Wednesday, September 02, 2015 9:27 PM Subject: RE: AeroElectric-List: RE: Request for some direction and advise Bob, Success! I thank you for sending me in the proper direction to find this problem. I would never have figured out that it was RF loose in the cockpit. While I was checking for where I could possibly have a loose connection this afternoon, I removed the radio from the tray and measured both the length of the radio and the distance it had to reach to the connectors in the back plate. Whoops! Looks like the radio needs to be seated deeper into the tray! Stupid builder tricks! When I installed the radio, I installed a bezel around them and to make it look nicer, I put the bezel under the faceplate on the radio. The radio passed the test Garmin has for that, (three turns of the screw after the radio powers on) but apparently over time it got looser and looser and started having more and more symptoms. I modified the bezel this afternoon so the radio would properly seat and the problem appears to have resolved. I was getting a huge RF leak from the back of the radio prior to it getting into the coax. I am completing my conditional inspection so it will be a few days before I can fly and see just what symptoms I have fixed. Thanks, Bob! Bill ------------------------------------------------------------------------- ----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Wednesday, September 02, 2015 12:53 PM To: aeroelectric-list(at)matronics.com Subject: RE: AeroElectric-List: RE: Request for some direction and advise One other thing that I just thought of that may be a factor. The backing plate through connectors that the radio slides into when it is inserted into the tray are very wobbly. It is very easy to make a circle with them that is at least 1/8 inch in radius. I have never thought about these connectors before because I thought that they were wobbly in order to line up with the radio when in is inserted. But now thinking about it, it seems to me that they should firm up when the radio is inserted because they are making rigid contact with the radio?? Mine are still wobbly after the radio is inserted. Could these connectors or the backing plate be somehow incorrectly installed? Tray connectors often 'float' on the tray itself so as to accommodate dimenational differences between tray and radio as the radio is slid into the tray. Similarly, your antenna connectors a the back of the radio may appear 'loose' in spite of having perfect electrical integrity. http://tinyurl.com/qa5hr7l In the image sited above, we see where electrical integrity is achieved as a separate component of mechanical mounting. A BNC connector attached to an appliance. http://tinyurl.com/pmy4hsg In the video above, we see that a connector is "loose" to move in some regard while mantaining electrical integrity of the connection. Does anyone know if these connectors should be firm after the radio is installed? Could this be where I have a bad connection with the shield? The connections I am most concerned about are between the coax shield and it's terminating connector. What about the other shield grounds described below? Would they be a factor if that card edge connector does not make a firm connection? There is a boss just to the side of this card edge connector that I am considering using to run a separate ground wire from the backing plate to the =13forest of tabs=14 ground block. Are there any opinions on this idea? Your symptoms scream of antagonistic disruption of TWO different systems that suggest a problem with the level of RF in the cockpit due to an antenna system problem . . . not with the radio's power/signal wires. Bob . . . http://www.matronics.com/Navigator?AeroElectric-Listhttp://forums.matroni cs.comhttp://www.matronics.com/contribution ________________________________________________________________________________
From: DeWitt Whittington <dee.whittington(at)gmail.com>
Date: Sep 03, 2015
Subject: Re: Degaussing tools
I have a similar tool, but mine is a rather large coil with a handle. It plugs into 120v AC, also has a button to energize it and was designed to erase magnetic tape for a tape recorder. Worked really well. Guess it would work on magnetized steel tubing too? Dee DeWitt (Dee) Whittington Richmond, VA 804-677-4849 iPhone 804-358-4333 Home On Thu, Sep 3, 2015 at 12:51 PM, Janet Amtmann wrote: > As a watch repairer many years ago I bought a degausser to demagnetize > watch tweezers. Nothing like a hairspring hanging on to the tweezers and > not letting go. It is (I still have it) a coil of wire around a 3" dia. > plastic tube with a zip cord and 115VAC plug on the end and a momentary > push button switch. Put the tool into the coil, push the button and slowly > withdraw the tool. Voila, no more captive hairsprings. If you release the > button with the tool in the coil, depending on the part of the cycle that > you released the switch, you may have made a real magnet out of your > miniature screw driver. That's the reason for withdrawing the tool slowly, > then releasing the switch. > > Jurgen Amtmann (RV-6A) > > * > > > * > > ________________________________________________________________________________
From: <rnjcurtis(at)charter.net>
Subject: AeroElectric-List:_OT:_Portable_LORAN_reciever?
Date: Sep 03, 2015
DQoNCkkndmUgZ290IGEgdmlydHVhbGx5IHVudXNlZCBSYXkgSmVmZiBwb3J0YWJsZSBMT1JBTiB1 bml0IChsdWNreSBtZSkgYW5kIA0KSSdtIHdvbmRlcmluZyBpZiBhbnlvbmUga25vd3Mgb2YgYW55 IHVzZSBmb3IgaXQsIGdpdmVuIHRoYXQgdGhlcmUgYXJlIG5vIA0KbG9uZ2VyIGFueSBMT1JBTiBz aWduYWxzLg0KDQpJIGZpZ3VyZSBpbiBhbnkgZ3JvdXAgb2YgcGVvcGxlIG1pZ2h0IGtub3csIGl0 J3MgdGhpcyBvbmUuDQoNCmRvIG5vdCBhcmNoaXZlDQoNCg0KDQpJZiB5b3UgaGF2ZSBhbiBvZmZp Y2Ugd2l0aCBhIGxvdCBvZiBsb29zZSBwYXBlciBhbmQgYW4gb3BlbiB3aW5kb3csIGl0IGNvdWxk IGJlIHVzZWQgdG8ga2VlcCB0aGUgcGFwZXJzIGluIHBsYWNlISEgICAgIOKYuiAgICAg4pi6DQoN Cg0KUm9nZXI ________________________________________________________________________________
Subject: Pitot Heat Ground
From: "JDA_BTR" <dudley(at)jdatkinson.net>
Date: Sep 08, 2015
I read the faqs, and know the recommendation to just take the pitot ground to the chassis. But I have a specific situation in mind, and would like some thoughts on it. I'm building an RV14 and the pitot heat controller will be about 4 feet outboard of an ADAHRS in the wing with a built in magnetometer. I figured if I ran the 14V/Gnd pair together as far from the magnetometer as possible I stood a chance of not interfering with it when the heater is on. I've gotten a Dynon heated pitot tube with controller. In this controller the aluminum controller box is connected to ground as is the ground lead leaving the box. Dynon says to a) not use the box for ground, and b) run a ground wire all the way to the battery. So I'm struggling with the idea that my ground wire will return the current to the battery in a sufficient way to stifle interference of the ADAHRS magnetometer. I figure a lot of current will take the controller box path and a lot will take the wire path, but since I don't own two ammeters I won't be knowing for sure. So if the controller box is going to ground, seems like taking the ground wire to a lug near the box might as well be done, because I won't get an interference benefit running the ground wire back to the battery. Lots of people ground the controller locally without trouble despite the reccs by Dynon to run a wire all the way back. Anyone have an expert opinion? I'm about at the point of blowing off the long ground return and just getting a remote magnetometer if it makes a difference. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446897#446897 ________________________________________________________________________________
Date: Sep 08, 2015
Subject: Re: Pitot Heat Ground
From: Charlie England <ceengland7(at)gmail.com>
On Tue, Sep 8, 2015 at 4:55 PM, JDA_BTR wrote: > > I read the faqs, and know the recommendation to just take the pitot ground > to the chassis. > > But I have a specific situation in mind, and would like some thoughts on > it. I'm building an RV14 and the pitot heat controller will be about 4 > feet outboard of an ADAHRS in the wing with a built in magnetometer. I > figured if I ran the 14V/Gnd pair together as far from the magnetometer as > possible I stood a chance of not interfering with it when the heater is on. > > I've gotten a Dynon heated pitot tube with controller. In this controller > the aluminum controller box is connected to ground as is the ground lead > leaving the box. Dynon says to a) not use the box for ground, and b) run a > ground wire all the way to the battery. > > So I'm struggling with the idea that my ground wire will return the > current to the battery in a sufficient way to stifle interference of the > ADAHRS magnetometer. I figure a lot of current will take the controller > box path and a lot will take the wire path, but since I don't own two > ammeters I won't be knowing for sure. > > So if the controller box is going to ground, seems like taking the ground > wire to a lug near the box might as well be done, because I won't get an > interference benefit running the ground wire back to the battery. Lots of > people ground the controller locally without trouble despite the reccs by > Dynon to run a wire all the way back. > > Anyone have an expert opinion? > > I'm about at the point of blowing off the long ground return and just > getting a remote magnetometer if it makes a difference. > > > My 1st inexpert reaction is, why is the magnetometer 'built in' the same wing as the heated pitot? And 2nd reaction is, why can't it be built into (moved to) the other wing? Never built a -14 or installed a Dynon, but I'll bet their install instructions for the magnetometer say to keep it as far away from high current wires and RF as possible. ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: "JDA_BTR" <dudley(at)jdatkinson.net>
Date: Sep 08, 2015
It's a good thought. The ADAHRS location in the wing is very convenient to the pitot for AOA. The magnetometer can be had as a remote unit and put elsewhere. Nonetheless I would like to know about the situation as presented, because I'm curious - why would the controller box be grounded if it is so important to carry a ground wire all the way back to the battery; and when the faqs here say the ground can be local and simple. Would running that wire reduce magnetometer interference even if I ran it? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446901#446901 ________________________________________________________________________________
Date: Sep 08, 2015
Subject: Re: Pitot Heat Ground
From: Charlie England <ceengland7(at)gmail.com>
Again, inexpert opinion...But with a high-current device like a pitot tube heater, they are probably trying to guarantee a solid ground path for the heater. With all the variations in building techniques, and hundreds of 'joints' between the pitot & the battery negative, it's conceivable that one could have several ohms of resistance in the ground path when using the airframe. Could be worse with a tube/fabric airframe, through the steel. Another thought is that the instructions are intended to be 'universal', so no matter the airframe material, a good ground is provided. But I'd hope someone at Dynon could give you the real answer. If the magnetometer is built into the ADAHRS, you could just prepare for having to remote it (a few extra wires), and just try it before purchasing the extra magnetometer. On Tue, Sep 8, 2015 at 5:37 PM, JDA_BTR wrote: > > It's a good thought. The ADAHRS location in the wing is very convenient > to the pitot for AOA. The magnetometer can be had as a remote unit and put > elsewhere. > > Nonetheless I would like to know about the situation as presented, because > I'm curious - why would the controller box be grounded if it is so > important to carry a ground wire all the way back to the battery; and when > the faqs here say the ground can be local and simple. Would running that > wire reduce magnetometer interference even if I ran it? > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=446901#446901 > > ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: Daniel Hooper <enginerdy(at)gmail.com>
Date: Sep 08, 2015
There are a couple of potential answers to this. One simple one is that the ground connection between the chassis of the box and the power ground inside the box is not low-impedance. In designing circuits, you do what you can to minimize radiated and conducted noise, and one of these ways is to segregate grounds internally. The connection between the two may be a giant bonding braid, a screw through the board, or even a 1 MOhm resistor. Another reason that the installation manual may encourage a wire pair instead of a single conductor and chassis ground is that high current devices create larger magnetic fields. Magnetic fields are proportional to several things, two of which are current and current loop area. By taking two wires back to the battery, you minimize loop area. When using the chassis ground method, you have no real control over the loop area. There may be another line of reasoning, but that is only known to the engineer who wrote the installation manual unfortunately. I am not that guy, so I have no idea, but that should give you some possibilities to consider. Daniel > On Sep 8, 2015, at 5:37 PM, JDA_BTR wrote: > > > It's a good thought. The ADAHRS location in the wing is very convenient to the pitot for AOA. The magnetometer can be had as a remote unit and put elsewhere. > > Nonetheless I would like to know about the situation as presented, because I'm curious - why would the controller box be grounded if it is so important to carry a ground wire all the way back to the battery; and when the faqs here say the ground can be local and simple. Would running that wire reduce magnetometer interference even if I ran it? > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=446901#446901 > > > > > > > > > > ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: "JDA_BTR" <dudley(at)jdatkinson.net>
Date: Sep 09, 2015
I spoke with a knowledgeable person at Dynon and was told that the MOSFET power transistor in the controller uses the case for a heat sink and thus is grounded to same; so the ground to the chassis is by design and necessary. It will also be low impedance in this configuration. In a metal airplane even if a wire is carried back to the battery most if not all of the current will pass to the mounting points of the controller box; so grounding the box to the airframe locally will make as much sense as carrying a wire back to the battery. There won't be a way to make a balanced wire run for the pitot heat controller. I could mount the controller in the fuselage and run the actual pitot wires balanced out to the heater. Will have to consider that; but I'm thinking now to just wire it up and if the magnetometer is affected (likely) then I'll remote it to another location, or relocate the ADAHRS/magnetometer. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446911#446911 ________________________________________________________________________________
Subject: Engine Starter Stalling
From: "todehnal" <tomscub(at)gmail.com>
Date: Sep 09, 2015
Hi Guys, New kid on the block, and I am looking for some advice. I have been having starter stall on cold starts. It will stop the prop a couple of times, and then spin up and start fine. I have been chasing this for a couple of months now. By the way, this is a Rotax powered RV-12. I know that when this happens the starter solenoid chatters. I can hear it. This chatter is caused by another starter circuit interrupt on the RV-12 called the spar pin relay. This safety device ensures that the removable wings spar pins are fully engaged, then completed the circuit to the start relay. I am now analyzing the battery. I downloaded data from the Dynon skyview, searched the spreadsheet and came up with a chart that shows the battery voltage during a typical start. If someone could take a look at the link below and offer some thoughts about the battery performance, or offer other advice, I would greatly appreciate it. Neat chart, and you can see the compression cycles on the chart. Thanks.........Tom http://i296.photobucket.com/albums/mm182/tomscub/img002_zpsujxtzrle.jpg -------- RV-12 with Skyview Panel built EAB by my wife & I. First Flight: 11/21/13. It's a keeper....Tom Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446912#446912 ________________________________________________________________________________
Date: Sep 09, 2015
Subject: Re: Engine Starter Stalling
From: Charlie England <ceengland7(at)gmail.com>
On Wed, Sep 9, 2015 at 7:01 AM, todehnal wrote: > > Hi Guys, New kid on the block, and I am looking for some advice. I have > been having starter stall on cold starts. It will stop the prop a couple > of times, and then spin up and start fine. I have been chasing this for a > couple of months now. By the way, this is a Rotax powered RV-12. I know > that when this happens the starter solenoid chatters. I can hear it. This > chatter is caused by another starter circuit interrupt on the RV-12 called > the spar pin relay. This safety device ensures that the removable wings > spar pins are fully engaged, then completed the circuit to the start > relay. I am now analyzing the battery. I downloaded data from the Dynon > skyview, searched the spreadsheet and came up with a chart that shows the > battery voltage during a typical start. If someone could take a look at > the link below and offer some thoughts about the battery performance, or > offer other advice, I would greatly appreciate it. Neat chart, and you can > see the compression cycles on! > the chart. Thanks.........Tom > > http://i296.photobucket.com/albums/mm182/tomscub/img002_zpsujxtzrle.jpg > > -------- > RV-12 with Skyview Panel built EAB by my wife & I. > First Flight: 11/21/13. It's a keeper....Tom > > Where does the Dynon measure battery voltage? If it's measuring the voltage between its own B+ & ground terminals, it can't tell the difference between a weak battery and bad connections somewhere in the power circuit. They can be anywhere along the B+ path, or anywhere along the ground path back to the battery. Try monitoring the battery voltage with a separate meter connected directly to the battery terminals (the posts, not the cable terminals on the battery terminals). Watch the meter while cranking the engine, & see how far voltage drops. It's hard to get the time domain resolution on a digital meter that you see on the Dynon graph, so you might try pulling the Dynon fuse, & power the Dynon with a wire directly to the battery B+ terminal so it can see true battery voltage during cranking. Remember to run a ground wire from the Dynon directly to the battery ground terminal also, if you try this. If you see your voltage drops going to ~9-10volts instead of 6-8volts, then you probably have some bad connections somewhere in the circuit. If the battery is truly dropping to 6volts during cranking, then it's either not fully charged, or defective. (Or you've got a bad starter.) ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 09, 2015
IIRC the general guidance is that high current devices like pitot heat and landing lights, nav lights do not need separate ground wire back to grounding block, only sensitive low current electronic devices like radios, intercoms, etc need central grounding. I haven't flown yet, but have the Dynon heated pitot with the controller mounted within 6" of the pitot mast. If you can't mount the combined ADAHRS in the fuselage clear of magnetic influences. they also offer a separate, remote magnetometer that you could mount out near a wing tip. On 9/9/2015 4:32 AM, JDA_BTR wrote: > > I spoke with a knowledgeable person at Dynon and was told that the MOSFET power transistor in the controller uses the case for a heat sink and thus is grounded to same; so the ground to the chassis is by design and necessary. It will also be low impedance in this configuration. In a metal airplane even if a wire is carried back to the battery most if not all of the current will pass to the mounting points of the controller box; so grounding the box to the airframe locally will make as much sense as carrying a wire back to the battery. > > There won't be a way to make a balanced wire run for the pitot heat controller. > > I could mount the controller in the fuselage and run the actual pitot wires balanced out to the heater. Will have to consider that; but I'm thinking now to just wire it up and if the magnetometer is affected (likely) then I'll remote it to another location, or relocate the ADAHRS/magnetometer. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=446911#446911 > > ________________________________________________________________________________
From: <berkut13(at)berkut13.com>
Subject: Re: Active VOR antenna
Date: Sep 09, 2015
VOR antenna project update: I want to extend a big THANK YOU to all that helped with this project and tell you it was a complete success! We have been progressing through Phase I testing and the non-standard VOL/ILS antenna design is working splendidly. It is being used with a Garmin 650 (internal splitter) and locks onto VOR signals from 100mi @ 10,000=99 and has no problem at all with ILS capture either. It was made from RG-58 coax and a short scrap of 22-AWG wire for the counterpoise per the dimensions below. We are very pleased with it=99s performance and can=99t imagine that a standard antenna would perform any better in this application. Testing will continue to determine if there are any blind or degraded spots or freqs. But for now, mark it up as a successful alternate design! Thanks again! -James Berkut/Race 13 From: Robert L. Nuckolls, III Sent: Thursday, June 04, 2015 5:26 PM Subject: Re: AeroElectric-List: Active VOR antenna Jim, finished one of these and was disappointed in performance. The thing is so tiny that it's hard to troubleshoot, assembled a second just in case. I think the best plan-b for now is to install a quasi-sleeve dipole . . . except that the 'sleeve' is just a piece of wire. I forget how long you said your antenna conduit was, hopefully considerably more than 26". Make the antenna from wire stiff enough to push into the tube on the end of the coax. Wouldn't put a connector in the counterpoise. Just thread it to the ship's interior on installation and tape it sort out of the way. I've got a couple other antenna projects on the bench but some buys waving credit cards have purchased some keyboard/hammer-n-tongs time . . . and I've got a couple of pots boiling for B&C. I'd like to pursue the active antenna experiment. It would be useful to field test the idea in close proximity to transponder and vhf/comm transmitters! In the mean time, let's get your airplane flying. Bob . . . ________________________________________________________________________________
Subject: Re: Engine Starter Stalling
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 09, 2015
The Dynon system allows the builder to place the voltage sensing lead where ever he/she chooses. Could be where battery plus connects to the bus, could be most anywhere. I don't know where the RV-12 plans call for the connection, but with this aircraft built under EAB rules rather than ELSA, he didn't have to follow the plans. On 9/9/2015 5:44 AM, Charlie England wrote: > > > On Wed, Sep 9, 2015 at 7:01 AM, todehnal > wrote: > > > > > > Where does the Dynon measure battery voltage? If it's measuring the > voltage between its own B+ & ground terminals, it can't tell the > difference between a weak battery and bad connections somewhere in the > power circuit. They can be anywhere along the B+ path, or anywhere > along the ground path back to the battery. > > Try monitoring the battery voltage with a separate meter connected > directly to the battery terminals (the posts, not the cable terminals > on the battery terminals). Watch the meter while cranking the engine, > & see how far voltage drops. It's hard to get the time domain > resolution on a digital meter that you see on the Dynon graph, so you > might try pulling the Dynon fuse, & power the Dynon with a wire > directly to the battery B+ terminal so it can see true battery voltage > during cranking. Remember to run a ground wire from the Dynon directly > to the battery ground terminal also, if you try this. > > If you see your voltage drops going to ~9-10volts instead of 6-8volts, > then you probably have some bad connections somewhere in the circuit. > If the battery is truly dropping to 6volts during cranking, then it's > either not fully charged, or defective. (Or you've got a bad starter.) > http://www.matronics.com/contribution ________________________________________________________________________________
Subject: Fuse links
From: John Tipton <jmtipton(at)btopenworld.com>
Date: Sep 09, 2015
Hi Guys We will be using a (base) Z11 for our RV9a Q 1 - The only CB's in use (otherwise all fuses) will be the 'ALT FIELD' CB, and a pullable CB for the autopilot, the 'Alt Field' wire is fed with as 'fusable link', does the autopilot feed need the fusable link too (same source, ie main power bus feed, same run length) Q 2 - The Z11 endurance feed, does not have any protection, yet all (I think) other Z figures do have a fuse link feed. Lastly, when making up the fuse links, is it OK to finish off the end covering with 'shrink wrap' or should the covering have 'free air' circulation Regards John ________________________________________________________________________________
Subject: Re: Engine Starter Stalling
From: "todehnal" <tomscub(at)gmail.com>
Date: Sep 09, 2015
I did build my RV-12 under EAB rules. Pretty sure Dynon is monitoring the voltage at the Avionics Bus, right at the amperage shunt. As far as the starter, I have hooked a +12 volt lead directly to it, and it functions flawlessly. I also have removed, cleaned, and reattached every connection from the battery plus, through the master relay, through the start relay, and starter, and back to the battery ground post, with no change. I guess my real question should be, is it a problem when the active starter voltage dips below 7 volts? Not sure what I should typically be seeing here........Tom -------- RV-12 with Skyview Panel built EAB by my wife & I. First Flight: 11/21/13. It's a keeper....Tom Read this topic online here: http://forums.matronics.com/viewtopic.php?p=446927#446927 ________________________________________________________________________________
Subject: Re: Engine Starter Stalling
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 09, 2015
On 9/9/2015 11:04 AM, todehnal wrote: > > I did build my RV-12 under EAB rules. Pretty sure Dynon is monitoring the voltage at the Avionics Bus, right at the amperage shunt. As far as the starter, I have hooked a +12 volt lead directly to it, and it functions flawlessly. I also have removed, cleaned, and reattached every connection from the battery plus, through the master relay, through the start relay, and starter, and back to the battery ground post, with no change. I guess my real question should be, is it a problem when the active starter voltage dips below 7 volts? Not sure what I should typically be seeing here........Tom > > -------- > RV-12 with Skyview Panel built EAB by my wife & I. > First Flight: 11/21/13. It's a keeper....Tom > Does that mean that you *started the engine* by hooking a battery lead directly to the starter? Because if you removed the starter & just spun it up with the battery, that doesn't give you much useful info that you didn't already know (that the windings have some continuity and the bearings allow it to turn). If you're monitoring voltage anywhere except at the battery terminals, you really need to know actual battery voltage *at the battery posts* before proceeding further. If it's staying higher than 8-10 volts while cranking, and you're seeing 6 volts at the remote monitoring point, you've got high resistance somewhere in the power circuit between battery & monitoring point. Don't forget that every connection using a terminal on a wire is really *two* connections: the transition in the bolted joint, and the joint between the terminal and the wire itself, whether crimped or soldered. Voltage will typically drop to between 8 & 10 volts while under starting load. Dropping to 6 volts can often cause electronics to drop off line, & may cause relays to drop out, as well. Try eliminating 'stuff' that's between the battery & starter. Eliminate the master contactor by putting both heavy terminals on the same post (this will obviously power up the plane even with the master switch off). Try starting the engine & see if your symptoms change for the better. If so, likely bad contacts in the master contactor. No change? return to 'normal' configuration & move on. Temporarily eliminate the wing spar interlock by jumping across it's contacts, & try starting. If symptoms change, perhaps the interlock is misadjusted or its contacts are flaky, causing it to be intermittent with vibration. The above are just examples; follow the power circuit and eliminate or 'bridge' each joint in sequence. ________________________________________________________________________________
Date: Sep 09, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Engine Starter Stalling
At 07:01 AM 9/9/2015, you wrote: > >Hi Guys, New kid on the block, and I am looking for some advice. I >have been having starter stall on cold starts. It will stop the >prop a couple of times, and then spin up and start fine. I have >been chasing this for a couple of months now. By the way, this is a >Rotax powered RV-12. I know that when this happens the starter >solenoid chatters. I can hear it. This chatter is caused by >another starter circuit interrupt on the RV-12 called the spar pin >relay. This safety device ensures that the removable wings spar >pins are fully engaged, then completed the circuit to the start >relay. I am now analyzing the battery. I downloaded data from the >Dynon skyview, searched the spreadsheet and came up with a chart >that shows the battery voltage during a typical start. If someone >could take a look at the link below and offer some thoughts about >the battery performance, or offer other advice, I would greatly >appreciate it. Neat chart, and you can see the compression cycles >on the chart. Thanks.........Tom As Charlie points out, without knowing exactly where the Dynon gets its data, the value of that data is weak. The plots show that the voltage doesn't drop below 8v or so . . . normally too high for contactor 'chatter'. I suspect that the data is being gathered at the bus . . . which may well be a voltage different than what drives the starter and/or it's control contactor. Is this a new condition? What size and how old the battery. Have you load checked it? Is there a wiring diagram for the system you can share? Just for grins, you might try clipping a charge car battery across the ship's battery and repeat the cold start experiment to see if there's a marked difference in behaviors. Bob . . . ________________________________________________________________________________
Date: Sep 09, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
At 04:55 PM 9/8/2015, you wrote: > >I read the faqs, and know the recommendation to just take the pitot >ground to the chassis. > >But I have a specific situation in mind, and would like some >thoughts on it. I'm building an RV14 and the pitot heat controller >will be about 4 feet outboard of an ADAHRS in the wing with a built >in magnetometer. I figured if I ran the 14V/Gnd pair together as >far from the magnetometer as possible I stood a chance of not >interfering with it when the heater is on. > >I've gotten a Dynon heated pitot tube with controller. In this >controller the aluminum controller box is connected to ground as is >the ground lead leaving the box. Dynon says to a) not use the box >for ground, and b) run a ground wire all the way to the battery. NOBODY should ever need to run any applicance wire(s) ground or otherwise, directly to the battery. Can you point us to a copy of the system wiring diagram? Do you KNOW how much power the pitot heater needs? Bob . . . ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: Lyle Peterson <lyleap(at)centurylink.net>
Date: Sep 09, 2015
I was going to say what Bob says here. The battery posts are for one, and only one, purpose. That is the connect for the main supply cables for the vehicle. No other wire should be attached at that point. Terminal strips are for that purpose. Wiring connected directly to the battery posts will corrode. Even large battery cables will corrode internally. I have a ten inch cable that ran from the battery to the starter solenoid that was green under the insulation for its entire length. This reduces the useable conductor in the cable and restricts its ability to carry the required current. With smaller gauge wires that reduction is tantamount to cutting the wire. On 9/9/2015 12:06 PM, Robert L. Nuckolls, III wrote: > At 04:55 PM 9/8/2015, you wrote: >> >> >> I read the faqs, and know the recommendation to just take the pitot >> ground to the chassis. >> >> But I have a specific situation in mind, and would like some thoughts >> on it. I'm building an RV14 and the pitot heat controller will be >> about 4 feet outboard of an ADAHRS in the wing with a built in >> magnetometer. I figured if I ran the 14V/Gnd pair together as far >> from the magnetometer as possible I stood a chance of not interfering >> with it when the heater is on. >> >> I've gotten a Dynon heated pitot tube with controller. In this >> controller the aluminum controller box is connected to ground as is >> the ground lead leaving the box. Dynon says to a) not use the box >> for ground, and b) run a ground wire all the way to the battery. > > NOBODY should ever need to run any applicance > wire(s) ground or otherwise, directly to the > battery. Can you point us to a copy of the > system wiring diagram? Do you KNOW how much > power the pitot heater needs? > > > Bob . . . > > http://www.matronics.com/contribution ________________________________________________________________________________
From: Ryan Brown <ribrdb(at)gmail.com>
Date: Sep 09, 2015
Subject: Re: Pitot Heat Ground
I don't see anything in the dynon installation manual about connecting directly to the battery. http://dynonavionics.com/downloads/Install_Guides/Heated_Unheated_AOA_Pitot_Probe_Installation_Guide_-_Rev_C.pdf` It says: Do not connect the Black (Ground) wire to the airframe as a Ground connection. Doing so will introduce high currents (10A) into the airframe. This can introduce a significant voltage drop, and potentially cause engine instrumentation, avionics, and audio system electrical problems. Also it says the ground wire should be: Constant connection to ground (not routed through a switch or fuse / circuit breaker). Must be sized to conduct 10A with minimal voltage drop. Ground connection must be constant FOR PITOT HEAT STATUS LINE (White wire) to operate when the controller is powered Off or not functioning. On Wed, Sep 9, 2015 at 11:21 AM Lyle Peterson wrote: > I was going to say what Bob says here. The battery posts are for one, and > only one, purpose. That is the connect for the main supply cables for the > vehicle. No other wire should be attached at that point. Terminal strips > are for that purpose. > > Wiring connected directly to the battery posts will corrode. Even large > battery cables will corrode internally. I have a ten inch cable that ran > from the battery to the starter solenoid that was green under the > insulation for its entire length. This reduces the useable conductor in > the cable and restricts its ability to carry the required current. With > smaller gauge wires that reduction is tantamount to cutting the wire. > > > On 9/9/2015 12:06 PM, Robert L. Nuckolls, III wrote: > > At 04:55 PM 9/8/2015, you wrote: > > > > I read the faqs, and know the recommendation to just take the pitot ground > to the chassis. > > But I have a specific situation in mind, and would like some thoughts on > it. I'm building an RV14 and the pitot heat controller will be about 4 > feet outboard of an ADAHRS in the wing with a built in magnetometer. I > figured if I ran the 14V/Gnd pair together as far from the magnetometer as > possible I stood a chance of not interfering with it when the heater is on. > > I've gotten a Dynon heated pitot tube with controller. In this controller > the aluminum controller box is connected to ground as is the ground lead > leaving the box. Dynon says to a) not use the box for ground, and b) run a > ground wire all the way to the battery. > > > NOBODY should ever need to run any applicance > wire(s) ground or otherwise, directly to the > battery. Can you point us to a copy of the > system wiring diagram? Do you KNOW how much > power the pitot heater needs? > > > Bob . . . > > > * > > > * > > ________________________________________________________________________________
From: Tim Andres <tim2542(at)sbcglobal.net>
Subject: Re: Engine Starter Stalling
Date: Sep 09, 2015
Don't forget the ground side of the circuit, you can have high resistance anywhere. One diagnostic method is to put a volt meter in series with the ground circuit, ie one probe on the battery negative post and the other on the engine case. You should see about a volt or less while cranking. Do the same on the positive side next, battery positive post and the other on the terminal on the starter. Anything over a volt or so and you have high resistance in the circuit, which can then be easily found by moving the probe backwards from the starter measuring at each terminal toward the battery. Having said all that, your chattering solenoid is pretty typical of a weak battery. Tim Andres > On Sep 9, 2015, at 9:50 AM, Charlie England wrote: > > >> On 9/9/2015 11:04 AM, todehnal wrote: >> >> I did build my RV-12 under EAB rules. Pretty sure Dynon is monitoring the voltage at the Avionics Bus, right at the amperage shunt. As far as the starter, I have hooked a +12 volt lead directly to it, and it functions flawlessly. I also have removed, cleaned, and reattached every connection from the battery plus, through the master relay, through the start relay, and starter, and back to the battery ground post, with no change. I guess my real question should be, is it a problem when the active starter voltage dips below 7 volts? Not sure what I should typically be seeing here........Tom >> >> -------- >> RV-12 with Skyview Panel built EAB by my wife & I. >> First Flight: 11/21/13. It's a keeper....Tom > Does that mean that you *started the engine* by hooking a battery lead directly to the starter? Because if you removed the starter & just spun it up with the battery, that doesn't give you much useful info that you didn't already know (that the windings have some continuity and the bearings allow it to turn). > > If you're monitoring voltage anywhere except at the battery terminals, you really need to know actual battery voltage *at the battery posts* before proceeding further. If it's staying higher than 8-10 volts while cranking, and you're seeing 6 volts at the remote monitoring point, you've got high resistance somewhere in the power circuit between battery & monitoring point. Don't forget that every connection using a terminal on a wire is really *two* connections: the transition in the bolted joint, and the joint between the terminal and the wire itself, whether crimped or soldered. > > Voltage will typically drop to between 8 & 10 volts while under starting load. Dropping to 6 volts can often cause electronics to drop off line, & may cause relays to drop out, as well. Try eliminating 'stuff' that's between the battery & starter. > > Eliminate the master contactor by putting both heavy terminals on the same post (this will obviously power up the plane even with the master switch off). Try starting the engine & see if your symptoms change for the better. If so, likely bad contacts in the master contactor. > > No change? return to 'normal' configuration & move on. > > Temporarily eliminate the wing spar interlock by jumping across it's contacts, & try starting. If symptoms change, perhaps the interlock is misadjusted or its contacts are flaky, causing it to be intermittent with vibration. > > The above are just examples; follow the power circuit and eliminate or 'bridge' each joint in sequence. > > > > > > ________________________________________________________________________________
Date: Sep 10, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
> >But I'd hope someone at Dynon could give you the real answer. Agreed. I've had some conversation with Dynon in years past . . . conversations that gave the impression of solid technical competence. Given their successes in this market, your expectations for the quality of their support is not unwarranted. >If the magnetometer is built into the ADAHRS, >you could just prepare for having to remote it >(a few extra wires), and just try it before purchasing the extra magnetometer. > >On Tue, Sep 8, 2015 at 5:37 PM, JDA_BTR ><dudley(at)jdatkinson.net> wrote: >"JDA_BTR" <dudley(at)jdatkinson.net> > >It's a good thought.=C2 The ADAHRS location in >the wing is very convenient to the pitot for >AOA.=C2 The magnetometer can be had as a remote unit and put elsewhere. > >Nonetheless I would like to know about the >situation as presented, because I'm curious - >why would the controller box be grounded if it >is so important to carry a ground wire all the >way back to the battery; and when the faqs here >say the ground can be local and simple.=C2 Would >running that wire reduce magnetometer interference even if I ran it? Exactly, that "ground wire directly to the battery" phrase has popped up over the years in several OBAM aviation installation manuals . . . were anyone at King Radio, Collins, Narco or ARC to make such an assertion, the writer should be tasked with a "lunchtime learning session" for colleagues and instructed to "bring us up to date on the physics of your assertion." I would LOVE to be in the audience for THAT one! I'm not clear as to where the all the components are located on the airplane with respect to each other . . . pitot tubes are generally on the wing, the AHRS is out there too? Help me understand . . . Bob . . . ________________________________________________________________________________
Date: Sep 10, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
At 01:50 PM 9/9/2015, you wrote: >I don't see anything in the dynon installation manual about >connecting directly to the battery. ><http://dynonavionics.com/downloads/Install_Guides/Heated_Unheated_AOA_Pitot_Probe_Installation_Guide_-_Rev_C.pdf`>http://dynonavionics.com/downloads/Install_Guides/Heated_Unheated_AOA_Pitot_Probe_Installation_Guide_-_Rev_C.pdf` >It says: > >Do not connect the Black (Ground) wire to the airframe as a Ground >connection. Doing so will introduce high currents (10A) into the >airframe. This can introduce a significant voltage drop, and >potentially cause engine instrumentation, avionics, and audio system >electrical problems. Good find . . . the author of these words demonstrates a poor understanding of grounding for the purposes of achieving (1) reliable power to the device and (2) minimizing risk of noise propagation to other systems. >Also it says the ground wire should be: >Constant connection to ground (not routed through a switch or fuse / >circuit breaker). Must be sized to conduct 10A with minimal voltage >drop. Ground connection must be constant FOR PITOT HEAT STATUS LINE >(White wire) to operate when the controller is powered Off or not functioning. Just why anyone would run a ground wire through a switch is a mystery . . . It's sad to discover these kinds of muddy thought in the manuals for what should be a no-brainer installation. Those kinds of statement inject what I have dubbed a "divide by zero" factor into the document. Emacs! Whether you're a politician, engineer, philosopher, CEO . . . what ever. Validity of many hours/pages of ideas become suspect when you include the "divide by zero" assertion into your 'formula for success'. Such assertions will at best make the rest of your ideas suspect . . . if not nullify them entirely. It's sort like spending an hour on the phone with tech support before somebody notices that the thing isn't even plugged in . . . I used to have a contact in Dynon management . . . haven't talked in years. I'll see if he's even still there . . . Bob . . . ________________________________________________________________________________
From: Gerry Van Dyk <gerry.vandyk(at)eastlink.ca>
Date: Sep 10, 2015
Subject: Re: Pitot Heat Ground
Bob=2C perhaps I=27m misunderstanding this thread=2E You said=3A =3E =3E =3E =3E Just why anyone would run a ground wire through a =3E switch is a mystery =2E =2E =2E- =3E =3E It=27s sad to discover these kinds of muddy thoughts =3E in the manuals for what should be a no-brainer =3E installation=2E =3E =3E =3E The quote from the installation manual is=3A =3E =3E =3E =3E =3E =3E Constant connection to ground (NOT routed through a switch or fu se / circuit breaker)=2E =3E =3E =3E =3E Isn=27t the manual telling the installer to bring the ground wire back t o the main ground block=2C presumably the forest-of-tabs on the firewall =3F Why would this manual be cause for concern=3F Gerry ________________________________________________________________________________
Date: Sep 10, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
>>>Constant connection to ground (NOT routed through a switch or fuse >>>/ circuit breaker). >Isn't the manual telling the installer to bring the ground wire back >to the main ground block, presumably the forest-of-tabs on the >firewall? Why would this manual be cause for concern? Why would such a statement even be necessary? Are there cases in the wild where someone's on-purpose design did take ground through a fuse or switch? The mere mention this would probably bring smiles to the system integrators at Textron but it plant's seeds of an exceedingly poor idea in the minds of their target market . . . the neophyte builder/installer. "Gee, are there instances where ground paths SHOULD go through switches or breakers?" This is why I have always encouraged folks to supply lucid wiring schematics with their products. No pictograms. Schematics are to electronics as numbers and operator symbols to mathematicians. The universal language understanding of how best to assemble something is the annotated schematic . . . like those you see in Appendix Z of the book, diagrams at the back of a Cesnna Service Manual, or the EXCELLENT diagrams published for KIA cars. Those diagrams offer a path for understanding between designers and users. I once spent a couple weeks in CA giving Japanese technicians an overview of a television time base corrector that my company built . . . and I wrote the manual for. Their English was poor, my Japanese nil, but they understood television, waveforms and SCHEMATICS. If an idea can be easily depicted on the wiring diagram, then do it. This completely negates the need for words. If words ARE offered, they should re-enforce the schematic with very low risk for doubt. Words are 'icing' on a an underlying 'cake' that should stand alone on the language of universal symbology and mathematical expression. I would hope the author of the ground wire statement was simply trying to compensate for the lack of lucid illustrations. As we've seen in this thread, vagaries in the use and understanding of language have generated a whole lot of conversation trying to figure out what COULD have been described in a few lines on a page. Unfortunately, other words in the document do not suggest that the author has a good handle on how the various appliances on an airplane can be encouraged to happily co-exist. This may well be an example of a condition common to many tech manufacturers. Marketing hands down goals, engineering designs to the goals, production experts package and manufacture the thing and 'tech writers' put out the books. It's the Silo-Syndrome where good stuff can get blown to the winds as a task is pitched from one silo to the next. Bob . . . ________________________________________________________________________________
Date: Sep 10, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
At 04:55 PM 9/8/2015, you wrote: >Subject: AeroElectric-List: Pitot Heat Ground >From: "JDA_BTR" <dudley(at)jdatkinson.net> >To: aeroelectric-list(at)matronics.com > > >I read the faqs, and know the recommendation to just take the pitot >ground to the chassis. Let's see if we can zero in on the physics. Is The pitot heat controller in conductive enclosure? Does its ground wire make electrical connection to the enclosure? If the above are both 'yes' then run the power ground to a point on the airframe separate from but in the vicinity of where the controller lives in the airplane. Adding a 'ground wire' off to some other portion of the airplane is of no value. It will simply be a conductor of much higher resistance than the airframe and carry a exceedingly small proportion of pitot heater current. Bob . . . ________________________________________________________________________________
Date: Sep 10, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
Another 'point of physics' that goes to your question. I just went to the workbench, laid my handy military surplus compass on the bench then held a wire over the needle at the optimal angle to antagonize the readings. With 3A flowing in the wire, I had to lower it to within about 5 inches to detect any movement of the needle. 10A would probably produce noticed motion at 14 inches or so. The interference I noted was 1 degree or less. The most rigorous certification of hardware under DO160 for magnetic effects is 'category Z' which may produce 1 degree of deflection while located 0.3 meters away from the compass . . . or about 12 inches. My 'shade tree' magnetic effects experiment suggests that 12' of separation for a 10A conductor will produce no observable deflections from real magnetic heading. Bob . . . ________________________________________________________________________________
From: Gerald Champagne <gerald.champagne(at)gmail.com>
Date: Sep 10, 2015
Subject: Re: Pitot Heat Ground
On Thu, Sep 10, 2015 at 4:02 PM, Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > > With 3A flowing in the wire, I had to lower > it to within about 5 inches to detect any > movement of the needle. 10A would probably > produce noticed motion at 14 inches or so. > That doesn't sound right. The strength of a magnetic field should increase linearly with current, but should fall off as a function of distance cubed. A 3A current at 5 inches should show the same deflection as a 10A current at about 7.5 inches, not 14 inches. Did I miss something? Gerald ________________________________________________________________________________
Date: Sep 11, 2015
From: BobbyPaulk(at)comcast.net
Subject: Magnetometers
When we were building two Zodiacs in the same hangar at the same time we stored the kit parts on opposite sides of the hangar to keep the confusion to a minimum. When we were calibrating the remote magnetometer in my plane the compass indicated 230 degrees on a north heading. Nobody could figure it out. Every heading was over 90 degrees off. I had located the Dynon magnetometer in the tail cone to get it away from any electrical or RF energy. I finally realized I could move the compass over 180 degrees by just moving the rudder cables sitting still. Someone ( ? ) had stored my rudder cables just above a DC welding machine. Duh! We degauzed the cables as best we could but had to re-locate the magnetometer. It is now the most accurate compass I have ever flown behind. Near perfect on any heading. Bobby ________________________________________________________________________________
Date: Sep 11, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
>That doesn't sound right.=C2 The strength of a >magnetic field should increase linearly with >current, but should fall off as a function of >distance cubed.=C2 A 3A current at 5 inches >should show the same deflection as a 10A current >at about 7.5 inches, not 14 inches.=C2 Did I miss something? Nope . . . looks like I punched the 1/sqrt button instead of 1/3rdrt . . . thank's for the heads-up! Bob . . . ________________________________________________________________________________
Subject: Radio battery voltage?
From: Ron Burnett <ronburnett(at)charter.net>
Date: Sep 14, 2015
I have a Luscombe and use an ICOM radio/VOR on a Quantum rechargeable battery. On the radio I also use a 10 cell AA attached battery which measures 16 volts with new cells in it. My question is does this high battery voltage "trump" my 12.6 rechargeable? It seems to as my batteries keep needing to be replaced and I rarely need to charge the rechargeable. Inquiring minds want to know. Thanks, Ron Burnett N1131B Luscombe 8A N524RB RV-6A Sent from my iPad May you have the blessings of the Lord today. ________________________________________________________________________________
Subject: Re: Radio battery voltage?
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 14, 2015
On 9/14/2015 7:53 PM, Ron Burnett wrote: > > I have a Luscombe and use an ICOM radio/VOR on a Quantum rechargeable battery. On the radio I also use a 10 cell AA attached battery which measures 16 volts with new cells in it. > > My question is does this high battery voltage "trump" my 12.6 rechargeable? It seems to as my batteries keep needing to be replaced and I rarely need to charge the rechargeable. > > Inquiring minds want to know. > > Thanks, > > Ron Burnett N1131B Luscombe 8A > N524RB RV-6A > Are you saying that you're using an Icom portable, with a 10 cell internal battery pack, and you're supplying 12V to the same portable through its external power jack? If so, then 'it depends'. Some portables will charge the internal pack from the external power jack; some won't. But 12V won't charge a 16V battery pack, in any case. Some portables actually disconnect the internal battery pack when powered off the external power jack. Why not simply remove the battery pack & run off the 12V battery. If you lose the battery, reinstall the internal pack. ________________________________________________________________________________
Subject: Re: Radio battery voltage?
From: "user9253" <fransew(at)gmail.com>
Date: Sep 14, 2015
If two power sources are connected to a load, the load will draw all current from the higher voltage source and draw no current from the lower voltage source. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447070#447070 ________________________________________________________________________________
From: "Jim Kale" <jimkale(at)roadrunner.com>
Subject: Re: Radio battery voltage?
Date: Sep 14, 2015
The explanation below is true, but too simplistic. Most battery devices have a diode built in so that if a higher voltage is applied, the device will use power from the higher voltage source, but the diode will prevent current from flowing into the battery (lower voltage source in this case) If the battery is rechargeable, there may be a path to charge the battery while the device is using the higher source. However, with regard to non-rechargeable batteries, that would be bad news. Bottom line it all depends on how the device circuitry for using outside sources, and internal batteries. Let the user beware with regard to devices where the circuitry is not known. I once used an ICOM IC A-23 handheld radio. The instructions were unclear about recharging the rechargeable battery while using the external plug. I finally experimented at the risk of the handheld smoking. Turned out that my rechargeable batteries did charge while the radio used the higher external source voltage, and I did no harm to my handheld. However, the results may have been much less desirable. Jim Kale -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of user9253 Sent: Monday, September 14, 2015 9:30 PM Subject: AeroElectric-List: Re: Radio battery voltage? If two power sources are connected to a load, the load will draw all current from the higher voltage source and draw no current from the lower voltage source. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447070#447070 ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Low Air Pressure Sensor
From: Jared Yates <email(at)jaredyates.com>
I've found a desire to measure differential air pressure inside the engine cowl for cooling diagnostics. Some folks have used an old airspeed indicator for this role. Is there a better way for someone like me who doesn't have an old airspeed indicator? Perhaps some sensors that I could plug into a computer to record the measurements? Thanks in advance! ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Richard Girard <aslsa.rng(at)gmail.com>
Make a multi-channel manometer out of irrigation tubing. Cheap and easy. I think the Rotary engine site still has info on this. Rick Girard On Tue, Sep 15, 2015 at 11:03 PM, Jared Yates wrote: > I've found a desire to measure differential air pressure inside the engin e > cowl for cooling diagnostics. Some folks have used an old airspeed > indicator for this role. Is there a better way for someone like me who > doesn't have an old airspeed indicator? Perhaps some sensors that I coul d > plug into a computer to record the measurements? Thanks in advance! > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx <http://www.goodreads.com/author/show/43244.Groucho_Marx> ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Charlie England <ceengland7(at)gmail.com>
http://www.digikey.com/product-detail/en/MPX5010DP/MPX5010DP-ND/464054?WT.mc_id=IQ60891383-VQ6-41244574155-VQ16-c&wt.srch=1&wt.medium=cpc&WT.srch=1&WT.medium=cpc This has been used with a volt meter to do what you're after, but obviously would require a bit of fabrication. Once built, you could feed multiple devices to spare 0-5V inputs in an EFIS or engine monitor. The device(s) and their pressure tubing can remain in the cowl, or where ever they're needed, with only wires coming back to the cockpit. The water manometer Richard mentioned is a lot simpler to fabricate, but a lot a bit harder to use while in flight. Charlie On Tue, Sep 15, 2015 at 11:03 PM, Jared Yates wrote: > I've found a desire to measure differential air pressure inside the engine > cowl for cooling diagnostics. Some folks have used an old airspeed > indicator for this role. Is there a better way for someone like me who > doesn't have an old airspeed indicator? Perhaps some sensors that I could > plug into a computer to record the measurements? Thanks in advance! > > * > > > * > > ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: "user9253" <fransew(at)gmail.com>
Date: Sep 16, 2015
When you consider the cost of a pressure transducer and knowledge and skill required to connect it to a computer, buying an old airspeed indicator is easier and less expensive. Alternatives are a differential pressure gauge or a homemade manometer. Omega sells transducers and gauges. http://www.omega.com/pptst/PGL-25.html A manometer can be made with 3/8" clear plastic tubing. Form it into the shape of a "U" and fill it half full of water. Route the ends of the tubing to the two areas where pressure needs to be compared. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447106#447106 ________________________________________________________________________________
From: Kent or Jackie Ashton <kjashton(at)vnet.net>
Subject: Re: Low Air Pressure Sensor
Date: Sep 16, 2015
Jared, Maybe you only need to measure the pressure differential above and blow the cylinders. Lycoming recommends about 5=9D of water differential, depending on HP. This discussion on the Van=99s site gave me the idea for a good manometer arrangement. I used it to run some tests on a Long-ez that were informative. http://www.vansairforce.com/community/showthread.php?p=978583 -Kent > On Sep 16, 2015, at 12:03 AM, Jared Yates wrote: > > I've found a desire to measure differential air pressure inside the engine cowl for cooling diagnostics. Some folks have used an old airspeed indicator for this role. Is there a better way for someone like me who doesn't have an old airspeed indicator? Perhaps some sensors that I could plug into a computer to record the measurements? Thanks in advance! ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Jared Yates <email(at)jaredyates.com>
Thanks for the help! In this case I'm wanting to measure the differential before and after the oil cooler, but I'd also like to check above and below the cylinders eventually. I hadn't considered the manometer, but I'll look into that. On Wed, Sep 16, 2015 at 9:09 AM, Kent or Jackie Ashton wrote: > Jared, Maybe you only need to measure the pressure differential above an d > blow the cylinders. Lycoming recommends about 5=9D of water differ ential, > depending on HP. This discussion on the Van=99s site gave me the i dea for a > good manometer arrangement. I used it to run some tests on a Long-ez tha t > were informative. > http://www.vansairforce.com/community/showthread.php?p=978583 > > -Kent > > On Sep 16, 2015, at 12:03 AM, Jared Yates wrote: > > I've found a desire to measure differential air pressure inside the engin e > cowl for cooling diagnostics. Some folks have used an old > airspeed indicator for this role. Is there a better way for someone like > me who doesn't have an old airspeed indicator? Perhaps some sensors that > I could plug into a computer to record the measurements? Thanks in advan ce! > > ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 16, 2015
Many RVs in hot climates have issues with oil cooling. Solutions have included larger or more efficient coolers, in a few cases adding a second cooler. If the cooler is fed from the rear baffle by scat tubing. the differential will be a bit less than the differential above and below the cylinders, due to losses in the scat tubing and the drop through the cooler. On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: > Jared, Maybe you only need to measure the pressure differential above > and blow the cylinders. Lycoming recommends about 5 of water > differential, depending on HP. This discussion on the Vans site gave > me the idea for a good manometer arrangement. I used it to run some > tests on a Long-ez that were informative. > http://www.vansairforce.com/community/showthread.php?p=978583 > > -Kent >> On Sep 16, 2015, at 12:03 AM, Jared Yates wrote: >> >> I've found a desire to measure differential air pressure inside the >> engine cowl for cooling diagnostics. Some folks have used an old >> airspeed indicator for this role. Is there a better way for someone >> like me who doesn't have an old airspeed indicator? Perhaps some >> sensors that I could plug into a computer to record the measurements? >> Thanks in advance! ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Jared Yates <email(at)jaredyates.com>
Thanks Kelly, my theory is that my 4-into-1 exhaust system is radiating a lot of heat into the lower part of the engine, but before I build a new exhaust system to test that theory, I'd like to make sure that I'm getting good flow through the cooler. I don't have the airspeed advantage that the RVs have, being just a 100-knot airplane. On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen wrote: > kellym(at)aviating.com> > > Many RVs in hot climates have issues with oil cooling. Solutions have > included larger or more efficient coolers, in a few cases adding a second > cooler. If the cooler is fed from the rear baffle by scat tubing. the > differential will be a bit less than the differential above and below the > cylinders, due to losses in the scat tubing and the drop through the cool er. > > On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: > >> Jared, Maybe you only need to measure the pressure differential above >> and blow the cylinders. Lycoming recommends about 5=9D of water >> differential, depending on HP. This discussion on the Van=99s sit e gave me >> the idea for a good manometer arrangement. I used it to run some tests on >> a Long-ez that were informative. >> http://www.vansairforce.com/community/showthread.php?p=978583 >> >> -Kent >> >>> On Sep 16, 2015, at 12:03 AM, Jared Yates wrote: >>> >>> I've found a desire to measure differential air pressure inside the >>> engine cowl for cooling diagnostics. Some folks have used an old airsp eed >>> indicator for this role. Is there a better way for someone like me who >>> doesn't have an old airspeed indicator? Perhaps some sensors that I co uld >>> plug into a computer to record the measurements? Thanks in advance! >>> >> > =========== =========== =========== =========== > > ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 16, 2015
More options, if one measurement at a time is sufficient & you want plug&play: http://www.ebay.com/sch/i.html?_odkw=pressure+gauge&_osacat=0&_from=R40&_trksid=p2045573.m570.l1311.R10.TR9.TRC6.A0.H0.Xdifferential+pressure.TRS2&_nkw=differential+pressure+meter&_sacat=0 Some are <$40, ready to go. Charlie On 9/16/2015 8:45 AM, Jared Yates wrote: > Thanks for the help! In this case I'm wanting to measure the > differential before and after the oil cooler, but I'd also like to > check above and below the cylinders eventually. I hadn't considered > the manometer, but I'll look into that. > > On Wed, Sep 16, 2015 at 9:09 AM, Kent or Jackie Ashton > > wrote: > > Jared, Maybe you only need to measure the pressure differential > above and blow the cylinders. Lycoming recommends about 5 of > water differential, depending on HP. This discussion on the Vans > site gave me the idea for a good manometer arrangement. I used it > to run some tests on a Long-ez that were informative. > http://www.vansairforce.com/community/showthread.php?p=978583 > > -Kent >> On Sep 16, 2015, at 12:03 AM, Jared Yates > > wrote: >> >> I've found a desire to measure differential air pressure inside >> the engine cowl for cooling diagnostics. Some folks have used an >> old airspeed indicator for this role. Is there a better way for >> someone like me who doesn't have an old airspeed indicator? >> Perhaps some sensors that I could plug into a computer to record >> the measurements? Thanks in advance! > > ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 16, 2015
Could you put heat shields on top of the exhaust pipes.. while stainless is best, with enough standoff, even aluminum can work. I kind of doubt your exhaust would be heating the oil from the pipes. Maybe from blowby. Location of oil cooler and airflow can be tricky. Mooney got it wrong on their '60s version M20s, putting cooler low on front of cowling, which is a low pressure area, and in a max performance climb the airflow actually reverses. Problem was fixed by moving cooler to rear of engine baffling. On 9/16/2015 7:15 AM, Jared Yates wrote: > Thanks Kelly, my theory is that my 4-into-1 exhaust system is > radiating a lot of heat into the lower part of the engine, but before > I build a new exhaust system to test that theory, I'd like to make > sure that I'm getting good flow through the cooler. I don't have the > airspeed advantage that the RVs have, being just a 100-knot airplane. > > On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen > wrote: > > > > > Many RVs in hot climates have issues with oil cooling. Solutions > have included larger or more efficient coolers, in a few cases > adding a second cooler. If the cooler is fed from the rear baffle > by scat tubing. the differential will be a bit less than the > differential above and below the cylinders, due to losses in the > scat tubing and the drop through the cooler. > > On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: > > Jared, Maybe you only need to measure the pressure > differential above and blow the cylinders. Lycoming > recommends about 5 of water differential, depending on HP. > This discussion on the Vans site gave me the idea for a good > manometer arrangement. I used it to run some tests on a > Long-ez that were informative. > http://www.vansairforce.com/community/showthread.php?p=978583 > > -Kent > > On Sep 16, 2015, at 12:03 AM, Jared Yates > > wrote: > > I've found a desire to measure differential air pressure > inside the engine cowl for cooling diagnostics. Some > folks have used an old airspeed indicator for this role. > Is there a better way for someone like me who doesn't have > an old airspeed indicator? Perhaps some sensors that I > could plug into a computer to record the measurements? > Thanks in advance! > > > ========== > - > Electric-List" rel="noreferrer" > target="_blank">http://www.matronics.com/Navigator?AeroElectric-List > ========== > FORUMS - > eferrer" target="_blank">http://forums.matronics.com > ========== > b Site - > -Matt Dralle, List Admin. > rel="noreferrer" target="_blank">http://www.matronics.com/contribution > ========== > > > http://www.matronics.com/contribution ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 16, 2015
You don't need to test it; it *is* radiating a lot of heat. :-) But heat shields that will protect from radiant heat are relatively easy to make. Also, distance is a big factor (variation on inverse square law). Only areas where the exhaust is within an inch or two of the engine will it likely have any significant effect. Years ago, I played with reflective shielding on the oil pan of my O-320 (RV-4, very tight cowl and close crossover 4x2 exhaust) and it had no noticeable effect on oil temps. I'll bet you're on the right path, looking for air pressure differential issues. BTW, is the oil cooler mounted so that air can't get trapped in it? Trapped air can have a huge effect on a heat exchanger's efficiency. Got pics? Charlie On 9/16/2015 9:15 AM, Jared Yates wrote: > Thanks Kelly, my theory is that my 4-into-1 exhaust system is > radiating a lot of heat into the lower part of the engine, but before > I build a new exhaust system to test that theory, I'd like to make > sure that I'm getting good flow through the cooler. I don't have the > airspeed advantage that the RVs have, being just a 100-knot airplane. > > On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen > wrote: > > > > > Many RVs in hot climates have issues with oil cooling. Solutions > have included larger or more efficient coolers, in a few cases > adding a second cooler. If the cooler is fed from the rear baffle > by scat tubing. the differential will be a bit less than the > differential above and below the cylinders, due to losses in the > scat tubing and the drop through the cooler. > > On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: > > Jared, Maybe you only need to measure the pressure > differential above and blow the cylinders. Lycoming > recommends about 5 of water differential, depending on HP. > This discussion on the Vans site gave me the idea for a good > manometer arrangement. I used it to run some tests on a > Long-ez that were informative. > http://www.vansairforce.com/community/showthread.php?p=978583 > > -Kent > > On Sep 16, 2015, at 12:03 AM, Jared Yates > > wrote: > > I've found a desire to measure differential air pressure > inside the engine cowl for cooling diagnostics. Some > folks have used an old airspeed indicator for this role. > Is there a better way for someone like me who doesn't have > an old airspeed indicator? Perhaps some sensors that I > could plug into a computer to record the measurements? > Thanks in advance! > > ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Jared Yates <email(at)jaredyates.com>
Here's one of the oil cooler mounted. It's a 9-row cooler in a triangular bracket sold for the RV-10, and the outlet is the higher port: http://bearhawkblue.com/wp-content/uploads/IMG_6711.jpg Here's one that kind of shows the exhaust situation. It doesn't show well how the left side cylinders cross under the sump and very close to it: http://bearhawkblue.com/wp-content/uploads/IMG_6712.jpg I've been running about 140-150 degrees over ambient temp. After flying, the oil cooler body measures pretty close to the indicated oil temp with an infrared thermometer, and I've replaced the vernatherm with no measurable change. I have good reason to believe that the oil is flowing, which is why I'd like to verify that the air is flowing too. On Wed, Sep 16, 2015 at 10:42 AM, Charlie England wrote: > You don't need to test it; it *is* radiating a lot of heat. :-) But heat > shields that will protect from radiant heat are relatively easy to make. > Also, distance is a big factor (variation on inverse square law). Only > areas where the exhaust is within an inch or two of the engine will it > likely have any significant effect. Years ago, I played with reflective > shielding on the oil pan of my O-320 (RV-4, very tight cowl and close > crossover 4x2 exhaust) and it had no noticeable effect on oil temps. > > I'll bet you're on the right path, looking for air pressure differential > issues. BTW, is the oil cooler mounted so that air can't get trapped in i t? > Trapped air can have a huge effect on a heat exchanger's efficiency. Got > pics? > > Charlie > > On 9/16/2015 9:15 AM, Jared Yates wrote: > > Thanks Kelly, my theory is that my 4-into-1 exhaust system is radiating a > lot of heat into the lower part of the engine, but before I build a new > exhaust system to test that theory, I'd like to make sure that I'm gettin g > good flow through the cooler. I don't have the airspeed advantage that t he > RVs have, being just a 100-knot airplane. > > On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen > wrote: > >> kellym(at)aviating.com> >> >> Many RVs in hot climates have issues with oil cooling. Solutions have >> included larger or more efficient coolers, in a few cases adding a secon d >> cooler. If the cooler is fed from the rear baffle by scat tubing. the >> differential will be a bit less than the differential above and below th e >> cylinders, due to losses in the scat tubing and the drop through the coo ler. >> >> On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: >> >>> Jared, Maybe you only need to measure the pressure differential above >>> and blow the cylinders. Lycoming recommends about 5=9D of water >>> differential, depending on HP. This discussion on the Van=99s si te gave me >>> the idea for a good manometer arrangement. I used it to run some tests on >>> a Long-ez that were informative. >>> http://www.vansairforce.com/community/showthread.php?p=978583 >>> >>> -Kent >>> >>>> On Sep 16, 2015, at 12:03 AM, Jared Yates < >>>> email(at)jaredyates.com> wrote: >>>> >>>> I've found a desire to measure differential air pressure inside the >>>> engine cowl for cooling diagnostics. Some folks have used an old airs peed >>>> indicator for this role. Is there a better way for someone like me wh o >>>> doesn't have an old airspeed indicator? Perhaps some sensors that I c ould >>>> plug into a computer to record the measurements? Thanks in advance! >>>> >>> >> > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 16, 2015
OK. That engine install strongly resembles the RV-10 I have. ;-) That mount is not the most efficient, due to the need for the air to make a 90 to enter the cooler and a 90 to exit. Many -10 builders use an Airflow Performance cooler that is the same size as what Vans supplies, but has extra row of cooling fins. Some go up to IIRC the 2007 or 2008 size cooler. The -10 setup runs hot until wheel pants and fairings are installed, moving cruise from 155 to 165-170 range. I don't know if it is adequate at 100kt speed for an IO-540. On 9/16/2015 8:07 AM, Jared Yates wrote: > Here's one of the oil cooler mounted. It's a 9-row cooler in a > triangular bracket sold for the RV-10, and the outlet is the higher port: > http://bearhawkblue.com/wp-content/uploads/IMG_6711.jpg > > Here's one that kind of shows the exhaust situation. It doesn't show > well how the left side cylinders cross under the sump and very close > to it: > http://bearhawkblue.com/wp-content/uploads/IMG_6712.jpg > > I've been running about 140-150 degrees over ambient temp. After > flying, the oil cooler body measures pretty close to the indicated oil > temp with an infrared thermometer, and I've replaced the vernatherm > with no measurable change. I have good reason to believe that the oil > is flowing, which is why I'd like to verify that the air is flowing too. > > > On Wed, Sep 16, 2015 at 10:42 AM, Charlie England > > wrote: > > You don't need to test it; it *is* radiating a lot of heat. :-) > But heat shields that will protect from radiant heat are > relatively easy to make. Also, distance is a big factor (variation > on inverse square law). Only areas where the exhaust is within an > inch or two of the engine will it likely have any significant > effect. Years ago, I played with reflective shielding on the oil > pan of my O-320 (RV-4, very tight cowl and close crossover 4x2 > exhaust) and it had no noticeable effect on oil temps. > > I'll bet you're on the right path, looking for air pressure > differential issues. BTW, is the oil cooler mounted so that air > can't get trapped in it? Trapped air can have a huge effect on a > heat exchanger's efficiency. Got pics? > > Charlie > > On 9/16/2015 9:15 AM, Jared Yates wrote: >> Thanks Kelly, my theory is that my 4-into-1 exhaust system is >> radiating a lot of heat into the lower part of the engine, but >> before I build a new exhaust system to test that theory, I'd like >> to make sure that I'm getting good flow through the cooler. I >> don't have the airspeed advantage that the RVs have, being just a >> 100-knot airplane. >> >> On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen >> > wrote: >> >> > >> >> Many RVs in hot climates have issues with oil cooling. >> Solutions have included larger or more efficient coolers, in >> a few cases adding a second cooler. If the cooler is fed from >> the rear baffle by scat tubing. the differential will be a >> bit less than the differential above and below the cylinders, >> due to losses in the scat tubing and the drop through the cooler. >> >> On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: >> >> Jared, Maybe you only need to measure the pressure >> differential above and blow the cylinders. Lycoming >> recommends about 5 of water differential, depending on >> HP. This discussion on the Vans site gave me the idea >> for a good manometer arrangement. I used it to run some >> tests on a Long-ez that were informative. >> http://www.vansairforce.com/community/showthread.php?p=978583 >> >> -Kent >> >> On Sep 16, 2015, at 12:03 AM, Jared Yates >> > >> wrote: >> >> I've found a desire to measure differential air >> pressure inside the engine cowl for cooling >> diagnostics. Some folks have used an old airspeed >> indicator for this role. Is there a better way for >> someone like me who doesn't have an old airspeed >> indicator? Perhaps some sensors that I could plug >> into a computer to record the measurements? Thanks >> in advance! >> >> > > *ist" > target="_blank">http://www.matronics.com/Navigator?AeroElectric-Listtp://forums.matronics.com > _blank">http://www.matronics.com/contribution * > > > http://www.matronics.com/contribution ________________________________________________________________________________
Date: Sep 16, 2015
Subject: Re: Low Air Pressure Sensor
From: Jared Yates <email(at)jaredyates.com>
Thanks Kelly, an inadequate oil cooler size is a likely factor. Mine is only a 360 and not a 540, which is partly why I didn't start with the 13-row cooler in the first place. ________________________________________________________________________________
From: <rnjcurtis(at)charter.net>
Subject: =?utf-8?Q?Low_resistance_measurement?
Date: Sep 16, 2015
Qm9iLA0KDQoNCkkgYW0gaW50ZXJlc3RlZCBpbiBjb25zdHJ1Y3RpbmcgYSBsb3cgcmVzaXN0YW5j ZSBtZWFzdXJlbWVudCBhZGFwdG9yLiAgSSBoYXZlIGEgTE0zMzcuICBDYW4gSSB1c2UgdGhpcyBk ZXZpY2UsIGluIHBsYWNlIG9mIHRoZSBMTTMxNywgd2l0aCBhIHNtYWxsIG1vZGlmaWNhdGlvbiB0 byB5b3VyIHNjaGVtYXRpYz8NCg0KDQpSb2dlcg= ________________________________________________________________________________
Date: Sep 16, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Low Air Pressure Sensor
At 11:03 PM 9/15/2015, you wrote: >I've found a desire to measure differential air >pressure inside the engine cowl for cooling >diagnostics.=C2 Some folks have used an old >airspeed indicator for this role.=C2 Is there a >better way for someone like me who doesn't have >an old airspeed indicator?=C2 Perhaps some >sensors that I could plug into a computer to >record the measurements?=C2 Thanks in advance! The quick-n-dirty way is to acquire a low-differential- pressure like this http://tinyurl.com/pujah48 There's a number of ranges for these instruments on eBay. I've got a couple buried in stuff not yet unpacked from my move to M.L from Wichita. They ARE g-loading sensitive to a degree so stright-n- level measurements will be the most meaningful. An all electronic solution may present in the form of sensors like this" http://tinyurl.com/ps2adq9 Amplified analog outputs that can be readily observed on a multi-meter. No g-loading sensitivities. Also, you could use a gage sensor as opposed to a ported differential device as long as the sensor itself can be positioned at the lower pressure environs. Bob . . . ________________________________________________________________________________
Date: Sep 16, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Low resistance measurement
At 12:38 PM 9/16/2015, you wrote: >Bob, > >I am interested in constructing a low resistance measurement >adaptor. I have a LM337. Can I use this device, in place of the >LM317, with a small modification to your schematic? > >Roger > > Sure, any of the 3-terminal, adjustable regulators can be adapted to this service. Here's the schematic for the AEC9008-3 adapter Emacs! If you choose to include the 1.0 Amp excitation option, be aware that the regulator chip warms up rapidly. Make QUICK measurements or include appropriate heat sink. 0.1A measurements require no heat-sink. Bob . . . ________________________________________________________________________________
Date: Sep 09, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Pitot Heat Ground
At 04:55 PM 9/8/2015, you wrote: > >I read the faqs, and know the recommendation to just take the pitot >ground to the chassis. > >But I have a specific situation in mind, and would like some >thoughts on it. I'm building an RV14 and the pitot heat controller >will be about 4 feet outboard of an ADAHRS in the wing with a built >in magnetometer. I figured if I ran the 14V/Gnd pair together as >far from the magnetometer as possible I stood a chance of not >interfering with it when the heater is on. >I've gotten a Dynon heated pitot tube with controller. In this >controller the aluminum controller box is connected to ground as is >the ground lead leaving the box. Dynon says to a) not use the box >for ground, and b) run a ground wire all the way to the battery. > >So I'm struggling with the idea that my ground wire will return the >current to the battery in a sufficient way to stifle interference of >the ADAHRS magnetometer. I figure a lot of current will take the >controller box path and a lot will take the wire path, but since I >don't own two ammeters I won't be knowing for sure. Do I understand that the power ground for pitot heat connects to chassis ground of the controller? In other words, if there were NO external ground wire attached, the pitot heater would continue to function? >So if the controller box is going to ground, seems like taking the >ground wire to a lug near the box might as well be done, because I >won't get an interference benefit running the ground wire back to >the battery. Lots of people ground the controller locally without >trouble despite the reccs by Dynon to run a wire all the way back. Your reasoning seems sound. The LOWEST resistance ground path will be through the box mounting and the longer the ground wire, the lower will be its share of the load. >Anyone have an expert opinion? > >I'm about at the point of blowing off the long ground return and >just getting a remote magnetometer if it makes a difference. You're conducting the grand experiment. I think your interference effects will be minimal. If the ground currents were being carried on a linear hunk of structure adjacent to the magnetometer, the potential for interference is higher than for the fields associated with sheet current spread out over the area of the skin. Could you put the pitot tube on the other wing? But your gut feeling is correct . . . separate ground all the way to battery does not speak well of Dynon's grasp of the art and sciences involved. Were I designing such a beast, all power wiring between tube and box . . . and from box to ship's power would be on twisted pairs with the box providing EMC grounding only . . . power would float (this is the way the BIG guys do it). The Dynon manual speaks to about 3' of harness between box and tube? Does then cause you mount the control box close to the magnetometer? Bob . . . ________________________________________________________________________________
Date: Aug 16, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Alternator B-lead circuit protection
At 03:41 AM 8/7/2015, you wrote: > >Hi everyone. I have a quick question with regards to protecting >alternator B-leads. > >A lot of people do so with ANL fuses, yet I know some aircraft (like >my C150) do so with a circuit breaker. Of course, a disadvantage of >the ANL is that if it blew while on a trip, after fixing whatever >caused the problem, a person would have to source a new fuse which >could result in the aircraft being grounded waiting for one to be >shipped (are ANL fuses that easy to find? B-lead protection is a legacy design philosophy with roots dating back to generators . . . it pay homage to failure mode effects analysis rules that ASSUMES that even unthinkable/unlikely thing will happen and mitigates the effects. 99.999% of all circuit breakers and fuses installed on airplanes go the lifetime of the airplane NEVER being tasked with saving a wire at risk for fault, overheating and fire. Yet, we have installed tons of such devices on airplanes from C-140 to B-747 because it's 'never been a bad thing to do.' This knowledge combined with a fortuitous introduction to fuse bocks by a Bussmann salesman at OSH gave rise to the notion that we could save a LOT of weight, cost of ownership, installation time and panel space with no impact on a failure tolerant system. http://tinyurl.com/o3cjb84 Referring to the FARs we find that regulatory (and for the most part) good design practices will protect all but battery and engine cranking conductors from the ravages of a hard fault (we're talking perhaps 1000 amps here) . . . that Breakers http://tinyurl.com/oypxaot Current limiters http://tinyurl.com/k9tmfmh Fuses vs. breakers http://tinyurl.com/o9joztv http://tinyurl.com/pvmvs62 http://tinyurl.com/pw2bbgg Bob . . . ________________________________________________________________________________
From: <rnjcurtis(at)charter.net>
Subject: Re:_AeroElectric-List:_Low_resistance_measurement?
Date: Sep 16, 2015
VGhlIExNMzM3IGJlaW5nIGEgbmVnYXRpdmUgcmVndWxhdG9yLCBjYW4gdGhpcyBjaXJjdWl0IGJl IHVzZWQgYnkgcmV2ZXJzaW5nIHRoZSBiYXR0ZXJ5IHBvbGFyaXR5LCBvciB0aGVyZSBvdGhlciBp c3N1ZXM/DQoNCg0KUm9nZXINCg0KDQoNCg0KDQoNCkZyb206IG51Y2tvbGxzLmJvYkBhZXJvZWxl Y3RyaWMuY29tDQpTZW50OiDigI5XZWRuZXNkYXnigI4sIOKAjlNlcHRlbWJlcuKAjiDigI4xNuKA jiwg4oCOMjAxNSDigI4y4oCOOuKAjjI54oCOIOKAjlBNDQpUbzogYWVyb2VsZWN0cmljLWxpc3RA bWF0cm9uaWNzLmNvbQ0KDQoNCg0KDQpBdCAxMjozOCBQTSA5LzE2LzIwMTUsIHlvdSB3cm90ZToN Cg0KQm9iLA0KDQpJIGFtIGludGVyZXN0ZWQgaW4gY29uc3RydWN0aW5nIGEgbG93IHJlc2lzdGFu Y2UgbWVhc3VyZW1lbnQgYWRhcHRvci4gIEkgaGF2ZSBhIExNMzM3LiAgQ2FuIEkgdXNlIHRoaXMg ZGV2aWNlLCBpbiBwbGFjZSBvZiB0aGUgTE0zMTcsIHdpdGggYSBzbWFsbCBtb2RpZmljYXRpb24g dG8geW91ciBzY2hlbWF0aWM/DQoNClJvZ2VyDQoNCg0KIA0KDQogIFN1cmUsIGFueSBvZiB0aGUg My10ZXJtaW5hbCwgYWRqdXN0YWJsZSByZWd1bGF0b3JzDQogIGNhbiBiZSBhZGFwdGVkIHRvIHRo aXMgc2VydmljZS4gSGVyZSdzIHRoZSBzY2hlbWF0aWMNCiAgZm9yIHRoZSBBRUM5MDA4LTMgYWRh cHRlcg0KDQogRW1hY3MhIA0KDQogIElmIHlvdSBjaG9vc2UgdG8gaW5jbHVkZSB0aGUgMS4wIEFt cCBleGNpdGF0aW9uDQogIG9wdGlvbiwgYmUgYXdhcmUgdGhhdCB0aGUgcmVndWxhdG9yIGNoaXAg d2FybXMNCiAgdXAgcmFwaWRseS4gTWFrZSBRVUlDSyBtZWFzdXJlbWVudHMgb3IgaW5jbHVkZQ0K ICBhcHByb3ByaWF0ZSBoZWF0IHNpbmsuIDAuMUEgbWVhc3VyZW1lbnRzIA0KICByZXF1aXJlIG5v IGhlYXQtc2luay4NCg0KDQoNCiAgQm9iIC4gLiAu ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: D L Josephson <dlj04(at)josephson.com>
Date: Sep 16, 2015
> > I've found a desire to measure differential air pressure inside the engine > cowl for cooling diagnostics. Some folks have used an old airspeed > indicator for this role. Is there a better way for someone like me who > doesn't have an old airspeed indicator? Perhaps some sensors that I could > plug into a computer to record the measurements? Thanks in advance! The simplest is a Magnehelic gauge, search an auction site with 'magnehelic differential' and skip the ones where the pointer doesn't sit at zero in the picture. There are differential pressure sensors that produce an analog voltage output if you have logging capability, such as with an inexpensive logger like a Dataq DI-145. It is more of a project, with the requirement to set up a quiet regulated power source for the sensor. ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: D L Josephson <dlj04(at)josephson.com>
Date: Sep 16, 2015
> > I've found a desire to measure differential air pressure inside the engine > cowl for cooling diagnostics. Some folks have used an old airspeed > indicator for this role. Is there a better way for someone like me who > doesn't have an old airspeed indicator? Perhaps some sensors that I could > plug into a computer to record the measurements? Thanks in advance! The simplest is a Magnehelic gauge, search an auction site with 'magnehelic differential' and skip the ones where the pointer doesn't sit at zero in the picture. There are differential pressure sensors that produce an analog voltage output if you have logging capability, such as with an inexpensive logger like a Dataq DI-145. It is more of a project, with the requirement to set up a quiet regulated power source for the sensor. ________________________________________________________________________________
Date: Sep 16, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Low Air Pressure Sensor
> An all electronic solution may present in the > form of sensors like this" > >http://tinyurl.com/ps2adq9 > > Amplified analog outputs that can be readily > observed on a multi-meter. No g-loading sensitivities. > Also, you could use a gage sensor as opposed to a > ported differential device as long as the sensor > itself can be positioned at the lower pressure > environs. I dug around in the archives to see the last time I used one of these critters. ONLY about 13 years ago . . . http://tinyurl.com/qe4z856 Had to get some data on pitot-heater performance on a Beechjet. Two of the my DAS channels recorded pressure altitude and IAS as presented by a couple of amplified transducers. Got these nice traces on a 'short hop' to 41000 feet in the venerable ol' flight test airplane at RAC . . . http://tinyurl.com/qe4z856 Bob . . . ________________________________________________________________________________
Date: Sep 16, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Low resistance measurement
At 01:54 PM 9/16/2015, you wrote: >The LM337 being a negative regulator, can this circuit be used by >reversing the battery polarity, or there other issues? > >Roger Ooops . . . missed that. Yes, you can turn the battery around and it will work fine . . . Bob . . . ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 16, 2015
Not necessarily. Van's supplies the same cooler for both 360 and 540 engines. Most do find the 13 row 2006A cooler needed for the 540. Airflow systems also supplies a diverter plate to install inside the mount to ensure not all the air goes through the bottom half of the cooler. On 9/16/2015 8:50 AM, Jared Yates wrote: > Thanks Kelly, an inadequate oil cooler size is a likely factor. Mine > is only a 360 and not a 540, which is partly why I didn't start with > the 13-row cooler in the first place. > > http://www.matronics.com/contribution ________________________________________________________________________________
Subject: Re: Low Air Pressure Sensor
From: Charlie England <ceengland7(at)gmail.com>
Date: Sep 16, 2015
That SCAT tubing is a prime suspect. It has very high internal skin drag. A friend with an alt. engine in an RV had several inches of manifold pressure loss through about 4' of SCAT (admittedly, smaller diameter, but still....). Most of the RV guys have the cooler mounted on a similar wedge shaped 'adapter', but the side you have facing the firewall is typically the inlet, attached to a hole in the engine baffle where you have your SCAT tube fitting. Your SCAT inlet would be blocked off (no opening). Yes, there are lots of cracked baffles until the baffle gets reinforced. :-) But most do cool adequately. Probably a minor factor, but the cooler exit in the pic is at 90 degrees to likely flow exiting the cowl. I know that velocity is relatively low there, but little things do add up.... Charlie On 9/16/2015 10:07 AM, Jared Yates wrote: > Here's one of the oil cooler mounted. It's a 9-row cooler in a > triangular bracket sold for the RV-10, and the outlet is the higher port: > http://bearhawkblue.com/wp-content/uploads/IMG_6711.jpg > > Here's one that kind of shows the exhaust situation. It doesn't show > well how the left side cylinders cross under the sump and very close > to it: > http://bearhawkblue.com/wp-content/uploads/IMG_6712.jpg > > I've been running about 140-150 degrees over ambient temp. After > flying, the oil cooler body measures pretty close to the indicated oil > temp with an infrared thermometer, and I've replaced the vernatherm > with no measurable change. I have good reason to believe that the oil > is flowing, which is why I'd like to verify that the air is flowing too. > > > On Wed, Sep 16, 2015 at 10:42 AM, Charlie England > > wrote: > > You don't need to test it; it *is* radiating a lot of heat. :-) > But heat shields that will protect from radiant heat are > relatively easy to make. Also, distance is a big factor (variation > on inverse square law). Only areas where the exhaust is within an > inch or two of the engine will it likely have any significant > effect. Years ago, I played with reflective shielding on the oil > pan of my O-320 (RV-4, very tight cowl and close crossover 4x2 > exhaust) and it had no noticeable effect on oil temps. > > I'll bet you're on the right path, looking for air pressure > differential issues. BTW, is the oil cooler mounted so that air > can't get trapped in it? Trapped air can have a huge effect on a > heat exchanger's efficiency. Got pics? > > Charlie > > On 9/16/2015 9:15 AM, Jared Yates wrote: >> Thanks Kelly, my theory is that my 4-into-1 exhaust system is >> radiating a lot of heat into the lower part of the engine, but >> before I build a new exhaust system to test that theory, I'd like >> to make sure that I'm getting good flow through the cooler. I >> don't have the airspeed advantage that the RVs have, being just a >> 100-knot airplane. >> >> On Wed, Sep 16, 2015 at 10:01 AM, Kelly McMullen >> > wrote: >> >> > >> >> Many RVs in hot climates have issues with oil cooling. >> Solutions have included larger or more efficient coolers, in >> a few cases adding a second cooler. If the cooler is fed from >> the rear baffle by scat tubing. the differential will be a >> bit less than the differential above and below the cylinders, >> due to losses in the scat tubing and the drop through the cooler. >> >> On 9/16/2015 6:09 AM, Kent or Jackie Ashton wrote: >> >> Jared, Maybe you only need to measure the pressure >> differential above and blow the cylinders. Lycoming >> recommends about 5 of water differential, depending on >> HP. This discussion on the Vans site gave me the idea >> for a good manometer arrangement. I used it to run some >> tests on a Long-ez that were informative. >> http://www.vansairforce.com/community/showthread.php?p=978583 >> >> -Kent >> >> On Sep 16, 2015, at 12:03 AM, Jared Yates >> > >> wrote: >> >> I've found a desire to measure differential air >> pressure inside the engine cowl for cooling >> diagnostics. Some folks have used an old airspeed >> indicator for this role. Is there a better way for >> someone like me who doesn't have an old airspeed >> indicator? Perhaps some sensors that I could plug >> into a computer to record the measurements? Thanks >> in advance! >> >> > ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: Kelly McMullen <kellym(at)aviating.com>
Date: Sep 16, 2015
I just went through the Dynon Pitot Install manual as a refresher. I agree that whoever wrote the caution about not grounding the negative power lead to the wing, for a metal wing aircraft, makes zero sense, The peak current in question is 10 amps. Wings on multi-engine aircraft routinely serve as ground path for engine ground and starter currents. I would be surprised to see any magnetometer interference if the current were carried in the wing skin. The only issue would be the changing current as the controller maintained the set temp with more or less current. The compass calibration is now done in flight, so it could be done without pitot heat, then repeated with pitot heat to see if it degraded at all. I will have to look at my own install, but since the distance from wing mounting to forrest of tabs was about 12 ft. I probably just used a red/black 14 gauge twisted pair to my central grounding point. I do not understand mounting the Skyview ADAHRS in the wing if there is any reasonable place for it in the fuselage. If magnetic interference is the issue, Dynon sells a remote magnetometer that can be mounted near the outer end of either wing. Performance of the ADAHRS will be better in the fuselage than within the wing, even is staying within the recommended 6 ft of centerline, in a wing. On 9/9/2015 11:20 AM, Robert L. Nuckolls, III wrote: > At 04:55 PM 9/8/2015, you wrote: >> >> >> I read the faqs, and know the recommendation to just take the pitot >> ground to the chassis. >> >> But I have a specific situation in mind, and would like some thoughts >> on it. I'm building an RV14 and the pitot heat controller will be >> about 4 feet outboard of an ADAHRS in the wing with a built in >> magnetometer. I figured if I ran the 14V/Gnd pair together as far >> from the magnetometer as possible I stood a chance of not interfering >> with it when the heater is on. > > >> I've gotten a Dynon heated pitot tube with controller. In this >> controller the aluminum controller box is connected to ground as is >> the ground lead leaving the box. Dynon says to a) not use the box for >> ground, and b) run a ground wire all the way to the battery. >> >> So I'm struggling with the idea that my ground wire will return the >> current to the battery in a sufficient way to stifle interference of >> the ADAHRS magnetometer. I figure a lot of current will take the >> controller box path and a lot will take the wire path, but since I >> don't own two ammeters I won't be knowing for sure. > > Do I understand that the power ground for pitot > heat connects to chassis ground of the controller? > In other words, if there were NO external ground wire > attached, the pitot heater would continue to function? > >> So if the controller box is going to ground, seems like taking the >> ground wire to a lug near the box might as well be done, because I >> won't get an interference benefit running the ground wire back to the >> battery. Lots of people ground the controller locally without trouble >> despite the reccs by Dynon to run a wire all the way back. > > Your reasoning seems sound. The LOWEST resistance > ground path will be through the box mounting and > the longer the ground wire, the lower will be its > share of the load. > > >> Anyone have an expert opinion? >> >> I'm about at the point of blowing off the long ground return and just >> getting a remote magnetometer if it makes a difference. > > You're conducting the grand experiment. I think > your interference effects will be minimal. If > the ground currents were being carried on a linear > hunk of structure adjacent to the magnetometer, > the potential for interference is higher than > for the fields associated with sheet current spread > out over the area of the skin. Could you put the > pitot tube on the other wing? > > But your gut feeling is correct . . . separate ground > all the way to battery does not speak well of > Dynon's grasp of the art and sciences involved. > > Were I designing such a beast, all power wiring > between tube and box . . . and from box to ship's power > would be on twisted pairs with the box providing > EMC grounding only . . . power would float (this > is the way the BIG guys do it). > > The Dynon manual speaks to about 3' of harness > between box and tube? Does then cause you mount > the control box close to the magnetometer? > > > Bob . . . > > http://www.matronics.com/contribution ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: "DougW" <N1deltawhiskey(at)comcast.net>
Date: Sep 17, 2015
Bob, This has been a rather lengthy thread. Being somewhat confused by various elements of the discussion, and as a recent acquirer of the Dynon heated pitot, I decided to look at the latest installation instructions. On page 3-1, it states to keep wires to the controller and between the controller and pitot away from any magnetometer/ADHRS, as well as audio devices. On page 3-2, it states "Do not connect the Black (Ground) wire to the airframe as a Ground connection." On page 3-4, the figure shows the black wire going "To permanent connection to aircraft ground" I could not find anywhere where it indicated that the metal case of the controller was and electrical ground for the controller. As a longtime follower of your comments and advice, I have avoided using the airframe as a ground except at one point on the firewall where it is grounded to the electrical system ground. For my installation, I will be generally following this comment of yours even though my magnetometer is in the tail cone, well away from the pitot heat wiring path: Were I designing such a beast, all power wiring between tube and box . . . and from box to ship's power would be on twisted pairs with the box providing EMC grounding only . . . power would float (this is the way the BIG guys do it). However, given the state of the conversation, I am wondering it a resistance measurement has been made between the proposed installation site and a common electrical ground point. Also, as the current must flow through the single +12v wire to power the controller/pitot provide the electromagnetic interference that the originator of this thread is trying to avoid? Regards, Doug Windhorn Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447162#447162 ________________________________________________________________________________
Subject: Re: Pitot Heat Ground
From: "DougW" <N1deltawhiskey(at)comcast.net>
Date: Sep 17, 2015
Bob, This has been a rather lengthy thread. Being somewhat confused by various elements of the discussion, and as a recent acquirer of the Dynon heated pitot, I decided to look at the latest installation instructions. On page 3-1, it states to keep wires to the controller and between the controller and pitot away from any magnetometer/ADHRS, as well as audio devices. On page 3-2, it states "Do not connect the Black (Ground) wire to the airframe as a Ground connection." On page 3-4, the figure shows the black wire going "To permanent connection to aircraft ground" I could not find anywhere where it indicated that the metal case of the controller was and electrical ground for the controller. As a longtime follower of your comments and advice, I have avoided using the airframe as a ground except at one point on the firewall where it is grounded to the electrical system ground. For my installation, I will be generally following this comment of yours even though my magnetometer is in the tail cone, well away from the pitot heat wiring path: Were I designing such a beast, all power wiring between tube and box . . . and from box to ship's power would be on twisted pairs with the box providing EMC grounding only . . . power would float (this is the way the BIG guys do it). However, given the state of the conversation, I am wondering if a resistance measurement has been made between the proposed installation site and a common electrical ground point. I don't trust my airframe to conduct low resistance currents as it has been corrosion proofed internally. As the current for the heated pitot also must flow through the single +12v wire to power the controller/pitot, would this not provide the electromagnetic interference that the originator of this thread is attempting to avoid? Regards, Doug Windhorn Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447172#447172 ________________________________________________________________________________
Subject: Antenna troubleshooting
From: "donjohnston" <don@velocity-xl.com>
Date: Sep 19, 2015
I've got (what I think is) a peculiar antenna problem. Composite aircraft with foil antennas embedded in the wings per RST Engineering manual. I have discovered that I couldn't hear anything on Com2. All aspects of Com1 work fine. When I key the mic three times on Com2 (for airport information), I don't hear anything (no surprise). But if I switch to Com 1, I hear the announcement. Which indicates to me that the mic keying is being transmitted. (I haven't been able to do a voice check yet). As a test, I swapped the antennas to the radios. The problem moves with the antenna. So I figure it's either a bad connector termination, bad cable, or bad antenna. I'm planning on checking for continuity between the center conductor and shield from the radio to and the last connector which should tell me if it's the cable. Does anyone know of way to you have any suggestions as to how to determine if the antenna is causing the problem? Thanks, Don Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447249#447249 ________________________________________________________________________________
Subject: Re: Antenna troubleshooting
From: "user9253" <fransew(at)gmail.com>
Date: Sep 19, 2015
It is highly unlikely that the cable is bad unless it has been pinched or bent with too small of a radius. The most likely problem is a bad connection between the coax and one of its connectors or between connector and antenna. The antenna foil could be cracked. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447251#447251 ________________________________________________________________________________
Subject: Re: Antenna troubleshooting
From: "donjohnston" <don@velocity-xl.com>
Date: Sep 21, 2015
Problem identified and resolved. The BNC connector on the wing root had a short. I really thought that I checked each connector when I installed them. Either I missed this one (likely) or the short developed after (unlikely but I'm going with that explanation). Re-terminated and all is well. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447315#447315 ________________________________________________________________________________
Date: Sep 23, 2015
Subject: Re: Active VOR antenna
From: Hariharan Gopalan <rdu.hari(at)gmail.com>
Hi Bob Will this antenna design work on an all metal plane? A fiberglass wingtip is used though. Thanks Hari On Wed, Sep 9, 2015 at 10:26 AM, wrote: > > VOR antenna project update: > > I want to extend a big THANK YOU to all that helped with this project and > tell you it was a complete success! > > We have been progressing through Phase I testing and the non-standard > VOL/ILS antenna design is working splendidly. It is being used with a > Garmin 650 (internal splitter) and locks onto VOR signals from 100mi @ > 10,000=99 and has no problem at all with ILS capture either. It wa s made > from RG-58 coax and a short scrap of 22-AWG wire for the counterpoise per > the dimensions below. > > We are very pleased with it=99s performance and can=99t imagi ne that a > standard antenna would perform any better in this application. Testing > will continue to determine if there are any blind or degraded spots or > freqs. But for now, mark it up as a successful alternate design! > > Thanks again! > -James > Berkut/Race 13 > > > *From:* Robert L. Nuckolls, III > *Sent:* Thursday, June 04, 2015 5:26 PM > *To:* aeroelectric-list(at)matronics.com > *Subject:* Re: AeroElectric-List: Active VOR antenna > > > Jim, finished one of these and was disappointed in performance. > The thing is so tiny that it's hard to troubleshoot, > assembled a second just in case. > > I think the best plan-b for now is to install > a quasi-sleeve dipole . . . except that the 'sleeve' > is just a piece of wire. I forget how long you said > your antenna conduit was, hopefully considerably > more than 26". > > Make the antenna from wire stiff enough to push > into the tube on the end of the coax. Wouldn't > put a connector in the counterpoise. Just thread > it to the ship's interior on installation and tape > it sort out of the way. > [image: Emacs!] > I've got a couple other antenna projects on the bench > but some buys waving credit cards have purchased some > keyboard/hammer-n-tongs time . . . and I've got a couple > of pots boiling for B&C. I'd like to pursue the > active antenna experiment. It would be useful to field > test the idea in close proximity to transponder and > vhf/comm transmitters! > > In the mean time, let's get your airplane flying. > > Bob . . . > ________________________________________________________________________________
Date: Sep 23, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Active VOR antenna
At 11:10 AM 9/23/2015, you wrote: >Hi Bob > >Will this antenna design work on an all metal plane? A fiberglass >wingtip is used though. No . . . suggest you consider a VOR tip antenna like this . . . http://tinyurl.com/qc9qyla Bob . . . ________________________________________________________________________________
Subject: Re: Active VOR antenna
From: "eschlanser" <eschlanser(at)yahoo.com>
Date: Sep 24, 2015
Is the BNC connector connected directly to the Garmin 650? A picture of the antenna would be a big help, if possible. Eric Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447416#447416 ________________________________________________________________________________
Date: Sep 24, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Active VOR antenna
At 01:08 PM 9/24/2015, you wrote: > >Is the BNC connector connected directly to the Garmin 650? >A picture of the antenna would be a big help, if possible. > >Eric Eric, that project has been put on the back burner . . . too many pots on the stove. Bob . . . ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: RE: Request for some direction and advice
Date: Sep 25, 2015
Well, here is an update to the sad state of affairs with the radio/autopilot. I found last Saturday that the problem was worse than it had ever been. Every time I keyed the mike, either the autopilot or the radio or both would power off, along with a lot of clicking in the headset. So I rigged up a separate coax and a separate antenna and tried transmitting through that setup. It didn't seem to make any difference. The problem was still the same. So I decided to try and find a local radio shop to take the plane to for them to check out. I contacted a couple of them and both told me that it sounded like a high resistance connection in either the power or ground circuit. By the way, I don't think I have mentioned that both these units are on the E-buss. So yesterday I went out and used a couple of VOM meters to see what the voltage did when I keyed the mike. I had one meter on the E-buss fuse block radio power wire just after the fuse and the ground connected to the radio back plate. The other meter was connected similarly to the autopilot. I couldn't get the problem to appear! Everything worked fine! No fricking clicking! The voltage would drop to the range of low 11 volts during transmission on both units. Turning on the E-buss diode bypass improved this by about a half volt. I put the batteries on charger and the voltage would hold around 12 volts. The meter that was connected to the autopilot had shorter leads and as a result it was physically closer to the radio. When I keyed the mike, this meter would usually go up to 15. 17. and even once to 20 volts. One of the radio shop guys told me that was caused by the radio and was not true voltage. This sounds like it may be proof that Bob is correct about RF leakage? Bottom line is that the radio and autopilot have (probably temporarily) fixed themselves. I doubt that this is permanent so further advise would be appreciated. Thanks, Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Bradburry Sent: Thursday, September 03, 2015 11:52 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advice Ok, I will report after I know more of what I have fixed..I am wildly optimistic at this point! I did check the coax connector at the antenna and it seemed solid. I really have no way to check the potted box at the antenna, but I do have a spare antenna just like it that I could try if necessary. I also have a piece of RG-400 about 10 ft long with connectors on both ends that I can try with both antennas. Bill _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, September 03, 2015 10:06 AM Subject: RE: AeroElectric-List: RE: Request for some direction and advise At 11:27 PM 9/2/2015, you wrote: Sounds like the project is moving forward again. Great! Let us know what you discover. As I recall, we still have a receiving noise issue that MIGHT be related to the antenna connector . . . but probably not. We can tackle that one after you've had more time to assess the state of your universe. Bob . . . http://www.matronics.com/Navigator?AeroElectric-List http://forums.matronics.com http://www.matronics.com/contribution ________________________________________________________________________________
Subject: Re: Request for some direction and advice
From: "user9253" <fransew(at)gmail.com>
Date: Sep 25, 2015
The vast majority of electrical problems are caused by bad connections. Those bad connections will be easier to find when the circuit is heavily loaded. I suggest that you connect a high wattage lamp in parallel with the problem avionics (using the same +12 volt and ground connections as the avionics). Then measure the voltage across the lamp. It should be pretty close to battery voltage. If not, then use the positive battery post as a reference and measure voltage drop along the positive half of the circuit. Then use the negative battery post as a reference and measure the voltage drop along the grounded side of the circuit. If all is well with the DC power, then check the radio antenna. Is the radio fully seated in its tray? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447436#447436 ________________________________________________________________________________
From: "David Lloyd" <skywagon(at)charter.net>
Subject: Re: Request for some direction and advice
Date: Sep 25, 2015
Joe is so right on this problem and his suggestion is the way to go. You need to push current thru the wiring path to find the flaw. While doing his method of checking for voltage drops, reach in and bump/jiggle all connections associated with the path being measured. And, lastly, read his last line again. This radio and tray thing/problem has been covered in the past. Again, one example is the Garmin 430 Navigators, etc. If the tray is bolted in "slightly" behind the planes "panel", then when the radio is inserted it will NOT fully seat with all the connectors in the rear of the tray. Because. . . the radio and its bezel during insertion is stopped at the front panel. And, thus it will never be fully seated. Randomly, the radio will loose a connection and go haywire. Fix is. . to remove the radio, unbolt the chassis tray and pull it forward to be even or maybe a tad ( 1/16" )forward of the front panel and rebolt it in place. D. Lloyd ----- Original Message ----- From: "user9253" <fransew(at)gmail.com> Sent: Friday, September 25, 2015 8:09 AM Subject: AeroElectric-List: Re: Request for some direction and advice > > The vast majority of electrical problems are caused by bad connections. > Those bad connections will be easier to find when the circuit is heavily > loaded. I suggest that you connect a high wattage lamp in parallel with > the problem avionics (using the same +12 volt and ground connections as > the avionics). Then measure the voltage across the lamp. It should be > pretty close to battery voltage. If not, then use the positive battery > post as a reference and measure voltage drop along the positive half of > the circuit. Then use the negative battery post as a reference and > measure the voltage drop along the grounded side of the circuit. > If all is well with the DC power, then check the radio antenna. Is the > radio fully seated in its tray? > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=447436#447436 > > > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________________________________________________________
From: "Bill Bradburry" <bbradburry(at)verizon.net>
Subject: Re: Request for some direction and advice
Date: Sep 25, 2015
Regarding the radio being seated in the tray. The tray was mounted just slightly proud of the panel. I then made a bezel to go around the radio stack. When I made the bezel, I tried to fit it around the top item in the stack which is a KMD150 moving map. I didn't do such a good job of fitting this bezel opening so I decided to place the bezel under the faceplate of the rest of the stack. This included the radio and the transponder. I realized this was a possible problem during this recent search and I opened the bezel up so that all the items in the stack could fit inside it. This seated the radio an sdditional 1/8 inch and as a result, the problems with the engine going haywire during transmit went away. This caused me to think that I had solved the problem. Apparently, not so fast! What ever this problem is, it is very intermittent. After reseating the radio, and the problem going away, the problem came back worse than it has ever been. Now, the last time I tried it, the problem has gone away again. Regarding the suggestions below. The avionics and ground connections end with a pin in a connector. I am not certain how I would connect a high wattage lamp in this circuit. Are we talking about like a landing light? Would this blow the fuse? How close is pretty close to battery voltage? If I checked the voltage at incremental steps in the circuit, what should I expect to see? Will the voltage drop a tenth or so volts at each connection? Or not much at all? I know I sound like a total idiot about electrical stuff, but unfortunately, what you hear is what you get. :>( When the problem was presenting itself I tried a different coax and a different antenna. I didn't see any change in the effect. Unless the problem is in the radio backplate or radio itself, I am not certain that it is an RF leak. However, I am also pretty certain that there is enough of an RF leak to cause the meter to go haywire even if the other stuff does not. Bill -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of user9253 Sent: Friday, September 25, 2015 10:10 AM Subject: AeroElectric-List: Re: Request for some direction and advice The vast majority of electrical problems are caused by bad connections. Those bad connections will be easier to find when the circuit is heavily loaded. I suggest that you connect a high wattage lamp in parallel with the problem avionics (using the same +12 volt and ground connections as the avionics). Then measure the voltage across the lamp. It should be pretty close to battery voltage. If not, then use the positive battery post as a reference and measure voltage drop along the positive half of the circuit. Then use the negative battery post as a reference and measure the voltage drop along the grounded side of the circuit. If all is well with the DC power, then check the radio antenna. Is the radio fully seated in its tray? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447436#447436 ________________________________________________________________________________
Subject: Re: Request for some direction and advice
From: "user9253" <fransew(at)gmail.com>
Date: Sep 25, 2015
A landing light would probably blow the fuse. How about an automotive brake light? A bigger fuse could be installed temporarily for a few minutes while testing. If a bad power connection is causing the autopilot to shut off, I would suspect that the bad connection is located between the bus and battery. If the radio power connections are not readily available, then test at the closest point that is available. The total voltage drop from the battery to radio should not be more than a few tenths. And that drop should be spread evenly over the entire circuit, not concentrated at any one connection. Do the voltage measurements suggested in my previous post while keying the transmitter. Are you sure that the battery is good? 11 volts is way too low. It should be closer to 13 volts, especially with the charger connected. It is normal for the E-bus diode to drop a half volt. The interface between the radio and its tray are highly suspect. Is there any way to measure the distance between the back of the radio and the back of the tray? > This sounds like it may be proof that Bob is correct about RF leakage? Bob is usually right. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447447#447447 ________________________________________________________________________________
Subject: Rotax 912 Noisy Regulator
From: "Guy Buchanan" <gebuchanan(at)cox.net>
Date: Sep 29, 2015
A brief problem description: I changed from a fried Key West voltage regulator on the front of my firewall to a Rotax VR on the back of my firewall. (Kitfox w/ 912ULS.) Now the music input to my intercom (SLA-400 TSO) is muted because of noise coming into the intercom via the IC-200 radio. So far I've shielded the input all the way to the VR, tried a noise filter right in front of the DC bus, and a faraday cage over the VR. I've improved the problem to the point that I can hear the music up to about 3000 rpm, then it mutes. So I bought an oscilloscope and took some measurements today. I'm seeing a weird 20Hz 360mv spike downstream of the VR, and the VR input (generator output) looks terrible. (I thought it was a kind of square wave.) I can't seem to find what the 912 generator output is supposed to look like online. Any ideas? Any ideas what the downstream voltage spikes are? Thanks, -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447548#447548 Attachments: http://forums.matronics.com//files/a_vr_out_b_bus__2490_rpm_678.jpg http://forums.matronics.com//files/a_vr_in__b_vr_in_braid_2200_rpm_127.jpg http://forums.matronics.com//files/a_main_bus__b__2310rpm_200.jpg ________________________________________________________________________________
Date: Sep 30, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Rotax 912 Noisy Regulator
At 06:49 PM 9/29/2015, you wrote: > >A brief problem description: I changed from a fried Key West voltage >regulator on the front of my firewall to a Rotax VR on the back of >my firewall. (Kitfox w/ 912ULS.) Now the music input to my intercom >(SLA-400 TSO) is muted because of noise coming into the intercom via >the IC-200 radio. So far I've shielded the input all the way to the >VR, tried a noise filter right in front of the DC bus, and a faraday >cage over the VR. I've improved the problem to the point that I can >hear the music up to about 3000 rpm, then it mutes. So I bought an >oscilloscope and took some measurements today. I'm seeing a weird >20Hz 360mv spike downstream of the VR, and the VR input (generator >output) looks terrible. (I thought it was a kind of square wave.) I >can't seem to find what the 912 generator output is supposed to look >like online. Any ideas? Any ideas what the downstream voltage spikes are? The fact that you didn't have noise . . . an now you do suggests a change in WIRING of the alternator and rectifier/regulator. I'm guessing on where and how the various components are grounded. Electro-static shielding of wires, magnetic shielding of the rectifier/regulator are almost guaranteed to be no help with what appears to be a ground-loop situation. The 'noises' you observed are all quite normal for the components of an engine driven power generation system. The alternator is the most trashy device in any airplane but the noise levels are limited, known and easily managed in the design of potential victims. The now-you-have-it and then-you-didn't points strongly FIRST toward a change in grounding and SECOND toward an interference coupled magnetically between adjacent wires bundled together. ALL potential victims (radios, nav, entertainment systems should ground together ON the panel with a single robust ground feeder extending down to DC system grounds on the firewall. See View-A of http://tinyurl.com/6m3bk8k Bob . . . ________________________________________________________________________________
Subject: Re: Rotax 912 Noisy Regulator
From: "Guy Buchanan" <gebuchanan(at)cox.net>
Date: Sep 30, 2015
Bob, Thanks for the response. I have no "firewall ground bus" but do have the "Panel Ground" forest of tabs inside the firewall. The engine ground strap is passed through the firewall with a brass or bronze bolt. The few grounds I have from the engine side pass through the firewall to the forest of tabs. The penetration for these grounds is away from the penetration for the VR, but they then pass near to the VR, as do the wires from the battery to the positive bus. I have an avionics ground forest of tabs on the panel, but I think the only thing connected are the headset grounds. I don't think I connected the radio and intercom grounds to it. (Checking) As to wires bundled together, the VR input and output go through the same firewall penetration. That's bad, isn't it? They're together for a distance of maybe three inches, then separate. I think I could separate them completely if necessary. This same system worked fine with my Rotax 582 with the VR forward of the firewall. Replacing the 582 with the 912 with its VR behind the firewall seems to have resulted in more noise. I have tracked one possible ground loop with the tachometer ground. I'll check it for continuity and will try to update my wiring diagram and post it. Thanks again. -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447572#447572 ________________________________________________________________________________
Subject: Re: Rotax 912 Noisy Regulator
From: "user9253" <fransew(at)gmail.com>
Date: Sep 30, 2015
> the VR input and output go through the same firewall penetration. Does the voltage regulator output have to go through the firewall? Can it be connected directly to the main power bus though a fuse? Are the AC wires from the dynamo to the voltage regulator twisted? If they are too big to twist, how about using two pairs of smaller wires? Is the faraday cage made from steel or aluminum? Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447574#447574 ________________________________________________________________________________
Subject: Re: Rotax 912 Noisy Regulator
From: "Guy Buchanan" <gebuchanan(at)cox.net>
Date: Oct 01, 2015
OK Bob, You got me of my sorry, no good, lazy butt and checking ground loops. Starting at the inside firewall ground tabs I found the following loops: 1) 0 Ohms: Com ground (Normally attached to tabs) -> IC-200 radio neg. -> (Not sure of this link) -> IC-200 chassis body -> com antenna braid -> airframe at com antenna -> firewall -> tabs. 2) 1800 Ohms: Transponder ground (Normally attached to tabs) -> Transponder neg. -> Transponder case -> carbon fiber panel -> (Not sure of this link) -> airframe -> firewall -> tabs. 3) 1800 Ohms: Engine Information System (EIS) ground (Normally attached to tabs)-> EIS neg. -> EIS case -> carbon fiber panel -> (Not sure of this link) -> airframe -> firewall -> tabs. 4) 0 Ohms: Intercom ground (Normally attached to tabs)-> panel tabs -> (Not sure of this link) -> IC-200 chassis -> com antenna braid -> airframe at com antenna -> firewall -> tabs. I think I can isolate the transponder from the carbon panel, if it matters to com noise. Clearly I have two whopper ground loops in the com system which I'm not sure how to rectify, since the com antenna braid is grounded both to the com chassis and the airframe. The one wiring variation from your design was that for some reason I carried the com ground back to the firewall forest of tabs instead of grounding it at the panel tabs. I'll fix that. However I think I'll still have the ground loop through the antenna shield. (I'll check continuity between the antenna braid and IC-200 ground tomorrow.) Any suggestions regarding that loop? Thanks. -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447580#447580 ________________________________________________________________________________
Subject: Re: Rotax 912 Noisy Regulator
From: "Guy Buchanan" <gebuchanan(at)cox.net>
Date: Oct 01, 2015
OK I went out and confirmed that the IC-200 com antenna ground is connected to the radio chassis and on to the power ground. Therefore in order to avoid a ground loop I've got to break either the antenna ground or the power ground. (Right now the antenna braid is attached to ground at the radio chassis and the airframe at the antenna. It's attached at the antenna presumably to make the ground plane on my rag and tube aircraft.) Not sure how to avoid a ground loop here. -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447581#447581 ________________________________________________________________________________
From: "Trent Heidtke" <theidtke(at)cox.net>
Subject: Grounding Question On dual Buss Dual Battery Aircraft
Date: Oct 01, 2015
Hello everyone, I am new here, building a Prescott Pusher, and have a question. My plane is totally electric dependent and so I have been following the Aero Connection Diagram Z-19 which addresses an outline for a dual battery, single alternator, and totally electronic fuel injection system. Additionally, I have subscribed 100% to the wiring philosophy whereby all powered device grounds go directly to the battery running the device instead of the massive common ground to frame approach (I have a metal sub-frame with composite skins over it). As illustrated in Diagram Z-19, I have set up primary and secondary batteries and busses with diodes so that #1 fuel pump and ECU have power all the time from #1 battery. In case of battery failure, flipping secondary power switch sends power from #2 battery through the diode to #1 fuel pump and ECU. The challenge is that if I remain pure to the philosophy of power and ground for any device go to/from the same battery, #1 fuel pump and ECU are not grounded and so if secondary power switch is turned on, pump does not work...obviously since it is not grounded to #2 battery. So I could add a switch to switch grounds (another level of complexity), or, wire the grounds together at the fuel pump connection in the back of the plane. Which approach is better? It is not really addressed in the diagram..that I can interpret anyway. Maybe I am being overly cautious about the grounding thing but am trying desperately not to end up with ground loops - about 70% wired and so far so good, except for this condition. Any and all help appreciated... Thank you Trent ________________________________________________________________________________
From: Bob Verwey <bob.verwey(at)gmail.com>
Date: Oct 02, 2015
Subject: Re: Grounding Question On dual Buss Dual Battery Aircraft
Hey Trent, my favorite aeroplane! What power plant? On 2 October 2015 at 01:22, Trent Heidtke wrote: > Hello everyone, I am new here, building a Prescott Pusher, and have a > question. My plane is totally electric dependent and so I have been > following the Aero Connection Diagram Z-19 which addresses an outline for a > dual battery, single alternator, and totally electronic fuel injection > system. Additionally, I have subscribed 100% to the wiring philosophy > whereby all powered device grounds go directly to the battery running the > device instead of the massive common ground to frame approach (I have a > metal sub-frame with composite skins over it). As illustrated in Diagram > Z-19, I have set up primary and secondary batteries and busses with diode s > so that #1 fuel pump and ECU have power all the time from #1 battery. In > case of battery failure, flipping secondary power switch sends power from > #2 battery through the diode to #1 fuel pump and ECU. The challenge is > that if I remain pure to the philosophy of power and ground for any devic e > go to/from the same battery, #1 fuel pump and ECU are not grounded and so > if secondary power switch is turned on, pump does not work..obvi ously > since it is not grounded to #2 battery. So I could add a switch to switc h > grounds (another level of complexity), or, wire the grounds together at t he > fuel pump connection in the back of the plane. Which approach is better? > It is not really addressed in the diagram.that I can interpret a nyway. > Maybe I am being overly cautious about the grounding thing but am trying > desperately not to end up with ground loops =93 about 70% wired and so far so > good, except for this condition. Any and all help appreciated.. > > Thank you > > Trent > > * > =========== www.matronics.com/Navigator?AeroElectric-List> =========== =========== om/contribution> =========== > > * > > -- Best... Bob Verwey ________________________________________________________________________________
Subject: Re: Grounding Question On dual Buss Dual Battery Aircraft
From: "user9253" <fransew(at)gmail.com>
Date: Oct 02, 2015
Yes, you are being overly cautious about grounding and might create more serious problems. Connect the negative terminal of each battery to a common ground point and connect the negative side of all loads to that common point. Doing that will not create ground loops. Consider dual alternators instead of dual batteries, perhaps Z-13/8. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447588#447588 ________________________________________________________________________________
Subject: Re: Grounding Question On dual Buss Dual Battery
Aircraft
From: Kent or Jackie Ashton <kjashton(at)vnet.net>
Date: Oct 02, 2015
Ditto on avoiding ground loops (a small difference in ground potential at different ground points that causes a small current loop). In my Cozy, I pulled was puzzled for years by a squirrelly fuel pressure indicator. The FP sender was grounded at the engine, FP gauge grounded up front. It is really a problem with gauging systems that use tiny currents. Probably not so much with big-amp devices. -Kent > On Oct 2, 2015, at 9:38 AM, user9253 wrote: > > > Yes, you are being overly cautious about grounding and might create more serious problems. Connect the negative terminal of each battery to a common ground point and connect the negative side of all loads to that common point. Doing that will not create ground loops. > Consider dual alternators instead of dual batteries, perhaps Z-13/8. > > -------- > Joe Gores > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=447588#447588 > > > > > > > > > > ________________________________________________________________________________
Date: Oct 02, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Grounding Question On dual Buss Dual Battery
Aircraft At 01:13 AM 10/2/2015, you wrote: >Hey Trent, my favorite aeroplane! > >What power plant? > >On 2 October 2015 at 01:22, Trent Heidtke ><theidtke(at)cox.net> wrote: > >Hello everyone, I am new here, building a >Prescott Pusher, and have a question.=C2 My plane >is totally electric dependent and so I have been >following the Aero Connection Diagram Z-19 which >addresses an outline for a dual battery, single >alternator, and totally electronic fuel >injection system.=C2 Additionally, I have >subscribed 100% to the wiring philosophy whereby >all powered device grounds go directly to the >battery running the device instead of the >massive common ground to frame approach Please don't do this. See Figure Z-15. ONE ground for all potential antagonists on the firewall . . . batteries ground here too. This ground gets a good connnection to the welded frame as well. ONE ground for all potential victims on the panel with a single feed path between panel ground and firewall ground. It's okay to use the frame as a ground for remotely located antagonists . . . just don't run battery charging currents or starter currents through the frame. Had the pleasure of working with Mr. Prescott during my first tenure at Beech in the Targets Division. Bob . . . ________________________________________________________________________________
Date: Oct 02, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Grounding Question On dual Buss Dual Battery
Aircraft At 09:29 AM 10/2/2015, you wrote: > > >Ditto on avoiding ground loops (a small difference in ground >potential at different ground points that causes a small current >loop). In my Cozy, I pulled was puzzled for years by a squirrelly >fuel pressure indicator. The FP sender was grounded at the engine, >FP gauge grounded up front. It is really a problem with gauging >systems that use tiny currents. Probably not so much with big-amp devices. Actually, it was the BIG amp devices that generated the difference in potential between what was expected to be same-voltage-grounds. This was a common problem in early LongEz ships with no starter and a 30-40a alternator. The builder RATED his ground return from crankcase to battery(-) for ALTERNATOR currents . . . so 10A wire at 1 milliohm per foot x 15ft long x 30A would generate as much as 1/2 volt difference between CRANKCASE ground and BATTERY ground. Hence, engine grounded 'senders' would produce strange and variable readings as the alternator loads varied and only read correctly when the alternator was off. Problem was still there . . . only much smaller if the builder added a starter and the crankcase ground was up-sized to 4 or 2AWG. Seldom a problem on BIG airplanes. A Beechjet measures about .001 ohm from stem to stern . . . enough to experience significant differences in 'ground' potentials during lighting strikes . . . but seldom an issue for more mundane current flows circulating between system grounds. This is why potential victims are grounded at various locations about the airframe . . . thusly . . . http://tinyurl.com/odvpk6z . . . but the ground systems in smaller airplanes and of course composite aircraft are not so robust. Hence the need for artful grounding architectures. Bob . . . ________________________________________________________________________________
From: "Trent Heidtke" <theidtke(at)cox.net>
Subject: Grounding Question On dual Buss Dual Battery Aircraft
Date: Oct 02, 2015
Hi Bob, The Prescott Pusher I am building is using a Mazda 20B 3-rotor engine. I live in the AZ desert so particularly in the summer when going North to Prescott, Sedona, or Flagstaff I need a bit more than 200 HP/60 inch prop (original spec=99d items) to get me off the ground. Mazda 3-rotor was about the only weight/HP choice to keep W/B about as close to original as possible. Still about a year and a half from finishing but everything has been on it to check fit/function. Just trying to make sure I am doing wiring right at this point. Trent From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob Verwey Sent: Thursday, October 01, 2015 11:14 PM Subject: Re: AeroElectric-List: Grounding Question On dual Buss Dual Battery Aircraft Hey Trent, my favorite aeroplane! What power plant? On 2 October 2015 at 01:22, Trent Heidtke wrote: Hello everyone, I am new here, building a Prescott Pusher, and have a question. My plane is totally electric dependent and so I have been following the Aero Connection Diagram Z-19 which addresses an outline for a dual battery, single alternator, and totally electronic fuel injection system. Additionally, I have subscribed 100% to the wiring philosophy whereby all powered device grounds go directly to the battery running the device instead of the massive common ground to frame approach (I have a metal sub-frame with composite skins over it). As illustrated in Diagram Z-19, I have set up primary and secondary batteries and busses with diodes so that #1 fuel pump and ECU have power all the time from #1 battery. In case of battery failure, flipping secondary power switch sends power from #2 battery through the diode to #1 fuel pump and ECU. The challenge is that if I remain pure to the philosophy of power and ground for any device go to/from the same battery, #1 fuel pump and ECU are not grounded and so if secondary power switch is turned on, pump does not work..obviously since it is not grounded to #2 battery. So I could add a switch to switch grounds (another level of complexity), or, wire the grounds together at the fuel pump connection in the back of the plane. Which approach is better? It is not really addressed in the diagram.that I can interpret anyway. Maybe I am being overly cautious about the grounding thing but am trying desperately not to end up with ground loops =93 about 70% wired and so far so good, except for this condition. Any and all help appreciated.. Thank you Trent ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution -- Best... Bob Verwey ________________________________________________________________________________
From: "Trent Heidtke" <theidtke(at)cox.net>
Subject: Grounding Question On dual Buss Dual Battery
Aircraft
Date: Oct 02, 2015
Thank you Bob and everyone that replied to my request for help. It is very much appreciated. While I can read and implement schematics done by people way more intelligent than I, it is hard sometimes to discern the finer points that years of experience yields those who have been there and lived that. Based on the feedback, I am commencing to rewire the parts that need to be changed to comply more with the wisdom shared here. Regarding the Pusher project, it has been an amazing journey and both Ole Sindberg, and Tom Prescott have been immensely helpful (only 2 Prescott Pushers flying in the US to my knowledge). I hope that first flight will be in about 18 months now that I am back full time on the project. At present though, the wiring help will ensure success in that department so thank you all again. The next big challenge after wiring is making sure the Mazda 20B installation goes well. Glad there is an engine thread/forum as well for that=85. ;-) Trent From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Friday, October 02, 2015 8:28 AM Subject: Re: AeroElectric-List: Grounding Question On dual Buss Dual Battery Aircraft At 01:13 AM 10/2/2015, you wrote: Hey Trent, my favorite aeroplane! What power plant? On 2 October 2015 at 01:22, Trent Heidtke wrote: Hello everyone, I am new here, building a Prescott Pusher, and have a question.=C2 My plane is totally electric dependent and so I have been following the Aero Connection Diagram Z-19 which addresses an outline for a dual battery, single alternator, and totally electronic fuel injection system.=C2 Additionally, I have subscribed 100% to the wiring philosophy whereby all powered device grounds go directly to the battery running the device instead of the massive common ground to frame approach Please don't do this. See Figure Z-15. ONE ground for all potential antagonists on the firewall . . . batteries ground here too. This ground gets a good connnection to the welded frame as well. ONE ground for all potential victims on the panel with a single feed path between panel ground and firewall ground. It's okay to use the frame as a ground for remotely located antagonists . . . just don't run battery charging currents or starter currents through the frame. Had the pleasure of working with Mr. Prescott during my first tenure at Beech in the Targets Division. Bob . . . ________________________________________________________________________________
Date: Oct 02, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Grounding Question On dual Buss Dual Battery
Aircraft At 04:53 PM 10/2/2015, you wrote: >Hi Bob, >The Prescott Pusher I am building is using a >Mazda 20B 3-rotor engine.=C2 I live in the AZ >desert so particularly in the summer when going >North to Prescott, Sedona, or Flagstaff I need a >bit more than 200 HP/60 inch prop (original >spec=99d items) to get me off the >ground.=C2 Mazda 3-rotor was about the only >weight/HP choice to keep W/B about as close to >original as possible.=C2 Still about a year and a >half from finishing but everything has been on >it to check fit/function.=C2 Just trying to make >sure I am doing wiring right at this point. >Trent Understand. Have you crafted a load analysis and prioritized loads under various operating and failure modes? Bob . . . ________________________________________________________________________________
Subject: Re: Rotax 912 Noisy Regulator
From: "Guy Buchanan" <gebuchanan(at)cox.net>
Date: Oct 06, 2015
Score another one for Bob. Cleaned up three of the ground loops, including the intercom and radio and voila, the audio noise is gone and my music is no longer muted. Amazing. (Not really.) Thanks Bob. -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447739#447739 ________________________________________________________________________________
Date: Oct 07, 2015
Subject: Re: Rotax 912 Noisy Regulator
From: "j. davis" <jwd3ca(at)gmail.com>
Hi Guy... just out of curiosity, can you explain how you test for ground loops? Using an ohm meter, apparently, but hoe exactly? Thanks! On 6 October 2015 at 23:44, Guy Buchanan wrote: > gebuchanan(at)cox.net> > > Score another one for Bob. Cleaned up three of the ground loops, including > the intercom and radio and voila, the audio noise is gone and my music is > no longer muted. Amazing. (Not really.) > > Thanks Bob. > > -------- > Guy Buchanan > K-IV 1200 / 912Uls / Warp / 500 hours and flying again. > Now a glider pilot too. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=447739#447739 > > -- Regards, J. ----------------------------- J. Davis, - Zenith STOL CH750 C-FJNJ: Jab 3300, Whirlwind GA prop, Bing - Sonex #325 (ex)C-FJNJ, Jab 3300a, Prince P-Tip, Aerocarb - former C-IGGY CH701 owner/builder - see these and more at 'www dot cleco dot ca' web page ________________________________________________________________________________
Date: Oct 12, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Rotax 912 Noisy Regulator
At 09:57 AM 10/7/2015, you wrote: >Hi Guy... just out of curiosity, can you explain how you test for >ground loops? Using an ohm meter, apparently, but hoe exactly? Thanks! A 'ground loop' is said to exist when a potential antagonist (most often an alternator, motor or sometimes a strobe) shares a ground path with a potential victim (most often an audio system or some instrument that responds to millivolt level signals). Hence, the victim's performance is compromised by the DC/AC components of the antagonist's functionality. Ground loops are avoided with judicious attention to architecture where failure to 'avoid by design' cannot be readily detected except for the victim's mis-behaviors. I'm not sure how any sort of instrument or other measuring process would be useful in detecting/analyzing a ground loop. Bob . . . ________________________________________________________________________________
Subject: Re: detecting ground loops, was re: re: noisy 912 alternator
From: D L Josephson <dlj04(at)josephson.com>
Date: Oct 13, 2015
On 10/12/15 11:59 PM, AeroElectric-List Digest Server wrote: >> Hi Guy... just out of curiosity, can you explain how you test for >> ground loops? Using an ohm meter, apparently, but hoe exactly? Thanks! > > A 'ground loop' is said to exist when a potential > antagonist (most often an alternator, motor or > sometimes a strobe) shares a ground path with a > potential victim (most often an audio system or > some instrument that responds to millivolt level > signals). > > Hence, the victim's performance is compromised > by the DC/AC components of the antagonist's > functionality. Ground loops are avoided with > judicious attention to architecture where failure > to 'avoid by design' cannot be readily detected > except for the victim's mis-behaviors. > > I'm not sure how any sort of instrument or > other measuring process would be useful in > detecting/analyzing a ground loop. Some parts of the audio world are trying to get away from the name "ground loop" because the wording is confusing (it's seldom a loop and can be in the power lead, not just ground.) We are using the term "common impedance coupling" because a common path is used for two currents, variations in one being superimposed on the other. A differential scope is actually quite useful in analyzing this condition -- you look for AC signals with one probe connected to each end of the "ground" wire. David Josephson ________________________________________________________________________________
From: "Jim Kale" <jimkale(at)roadrunner.com>
Subject: Re: detecting ground loops, was re: re: noisy 912
alternator
Date: Oct 13, 2015
I have heard the term "Ground Loop" used a lot and as I understand the problem, it mostly occurs when a unit that is sensitive to very small fluctuations in voltage is used and the common ground circuit is not a single common point, but a lengthy circuit distributed around the airplane using wires or airframe components. This can lead to small resistances distributed along the common ground circuit. As current increases in the common ground circuit, these small resistances develop voltages along the common ground circuit. Electrical devices, (radios, etc.) that are sensitive to very small voltage differences and that are connected at different points along the ground circuit, sense the very small voltage and behave as if they are not connected to a common ground point, but to different values of ground. The solution seems to be to have a very current hefty single point (robust common Bus Bar) to connect each of the using devices to so that minor voltages cannot develop across distributed resistance in a long common ground path. A hefty bus bar (preferably near the alternator/battery current source): and all using devices have the common ground lead tied to that point. Is that a layman's description of the solution? This seems to be what is being discussed below. I am just trying to get it all straight in my brain. -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of D L Josephson Sent: Tuesday, October 13, 2015 2:39 AM Subject: AeroElectric-List: Re: detecting ground loops, was re: re: noisy 912 alternator --> On 10/12/15 11:59 PM, AeroElectric-List Digest Server wrote: >> Hi Guy... just out of curiosity, can you explain how you test for >> ground loops? Using an ohm meter, apparently, but hoe exactly? Thanks! > > A 'ground loop' is said to exist when a potential > antagonist (most often an alternator, motor or > sometimes a strobe) shares a ground path with a > potential victim (most often an audio system or > some instrument that responds to millivolt level > signals). > > Hence, the victim's performance is compromised > by the DC/AC components of the antagonist's > functionality. Ground loops are avoided with > judicious attention to architecture where failure > to 'avoid by design' cannot be readily detected > except for the victim's mis-behaviors. > > I'm not sure how any sort of instrument or > other measuring process would be useful in > detecting/analyzing a ground loop. Some parts of the audio world are trying to get away from the name "ground loop" because the wording is confusing (it's seldom a loop and can be in the power lead, not just ground.) We are using the term "common impedance coupling" because a common path is used for two currents, variations in one being superimposed on the other. A differential scope is actually quite useful in analyzing this condition -- you look for AC signals with one probe connected to each end of the "ground" wire. David Josephson ________________________________________________________________________________
Subject: Technique for DSub Pin / data breakout for RPM issue
From: "plevyakh" <hplevyak(at)mac.com>
Date: Oct 13, 2015
Folks, I've come across this a few times in the System Test and Flight test of my GlaStar. Can you please share a technique you've used to break into a DSub connector pin and read the data going through that Pin/Wire? Currently...I'm looking for something that will allow me to easily disconnect a DSub 15 and DSub25 connectors, insert the data Breakout board, and then read the data going through any Pin with a Voltmeter. I found this on eBay, and it would work, but I'd have to also get a short pigtail connector to enable the connections due to space. http://www.ebay.com/itm/DIN-Rail-Mount-D-SUB-Interface-Module-DSUB-Header-Breakout-Board-/191703597826?var=&hash=item2ca26cc302 Here's my recent flight test issue. I have dual LightSpeed Ignition System Plasma IIIs. The RPM sensor on Ignition #1 is working great! I feed this into my Grand Rapids EIS4000 engine monitor and get reliable RPM readings. My problem is with Lightspeed Ignition #2. When I switch to Ign #2 only, my RPM goes to zero. So either my Lightspeed #2 signal tach reading voltage is bad, or my connection to to the EIS4000 engine monitor is bad. I need to break into the Dsub 15 connector on the Lightspeed Ignition #2, and read Pin 6 (Signal Tach), and Pin 13 (Shield Ground) to confirm I'm getting 0V at idle, and 5V or higher at higher throttle settings. If this checks good, then I'll have to break into the EIS4000 DSub 25 connector and check Pin 24 (Tach Input #2) and see if it's sensing a value. Is there an easy way to break into a DSub and measure readings without having to pull apart the connector and patch in a test wire? Thanks for your experience'd inputs! Howard GlaStar N19HL (flying and loving every minute!) -------- Howard Plevyak GlaStar / North Bend, Ohio hplevyak(at)mac.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447881#447881 ________________________________________________________________________________
From: ARGOLDMAN(at)aol.com
Date: Oct 13, 2015
Subject: Re: Technique for DSub Pin / data breakout for RPM
issue One thing I have found helpful is to make a "jumper/diagnoser cable. Use a flat ribbon cable (much longer than you think that you need) and get several press-on sub d-s of both genders in vairous sizes (obviously the largest one (probably a 25 pin)) but also 15 and 9 pin ones. Be careful to keep the proper pin alignment as these press on things do not indicate pin 1. Start with a 25 pin male, a few inches down put a 25 pin female (again ascertain that pin 1 is correct then a few inches down put a 15 pin male then a 15 pin female and then a 9 pin male and female. if you want to use only 1 size use that size only. now in the middle just put a male plug (of each size for ease). At the other end of the wire put the same arrangement of plugs that you originally used in the beginning of the harness. What you now have is a jumper cable, usable for 3 or more sizes of sub-ds with a male (pins exposed) sub-d in the middle( or males of vaarious sizes)-- remember that the pin numbers (over 5, I believe) will be different as the d-subs get larger-- . With this cable, you can do invivo studies (all systems connected). this jumper cable can be used for many other things. Since I have a Cozy with rotary engine, I use tit to verify 9, 15 and 25 pin sub-ds from the IP to the FW. Just don't run over the cable with a chair (Don't ask me how I know the damage that causes.) Good luck (did I say make sure that the pins are on the appropriate wires Rich In a message dated 10/13/2015 10:10:07 A.M. Central Daylight Time, hplevyak(at)mac.com writes: --> AeroElectric-List message posted by: "plevyakh" Folks, I've come across this a few times in the System Test and Flight test of my GlaStar. Can you please share a technique you've used to break into a DSub connector pin and read the data going through that Pin/Wire? Currently...I'm looking for something that will allow me to easily disconnect a DSub 15 and DSub25 connectors, insert the data Breakout board, and then read the data going through any Pin with a Voltmeter. I found this on eBay, and it would work, but I'd have to also get a short pigtail connector to enable the connections due to space. http://www.ebay.com/itm/DIN-Rail-Mount-D-SUB-Interface-Module-DSUB-Header-Br eakout-Board-/191703597826?var=&hash=item2ca26cc302 Here's my recent flight test issue. I have dual LightSpeed Ignition System Plasma IIIs. The RPM sensor on Ignition #1 is working great! I feed this into my Grand Rapids EIS4000 engine monitor and get reliable RPM readings. My problem is with Lightspeed Ignition #2. When I switch to Ign #2 only, my RPM goes to zero. So either my Lightspeed #2 signal tach reading voltage is bad, or my connection to to the EIS4000 engine monitor is bad. I need to break into the Dsub 15 connector on the Lightspeed Ignition #2, and read Pin 6 (Signal Tach), and Pin 13 (Shield Ground) to confirm I'm getting 0V at idle, and 5V or higher at higher throttle settings. If this checks good, then I'll have to break into the EIS4000 DSub 25 connector and check Pin 24 (Tach Input #2) and see if it's sensing a value. Is there an easy way to break into a DSub and measure readings without having to pull apart the connector and patch in a test wire? Thanks for your experience'd inputs! Howard GlaStar N19HL (flying and loving every minute!) -------- Howard Plevyak GlaStar / North Bend, Ohio hplevyak(at)mac.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447881#447881 ________________________________________________________________________________
Date: Oct 13, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Technique for DSub Pin / data breakout for RPM
issue At 10:01 AM 10/13/2015, you wrote: > >Folks, >I've come across this a few times in the System Test and Flight test >of my GlaStar. Can you please share a technique you've used to >break into a DSub connector pin and read the data going through that Pin/Wire? here is a cheep/n/dirty that I've used many times using a short chunk of ribbon cable and the appropriate connectors. Of course, this is for signal/low-power levels only. Limit this technique to wire currents of 1A or less. Emacs! More robust techniques call for a specialized break-out fixture not unlike this Emacs! Here's a breakout box I built in a few hours to explore signals in a starter-generator controller. Your tool would, of course, be fitted with d-subs. Emacs! Here's a specific application example for examining data at altitude and 'from a distance'. Connectors on the left tied into a system back in the hell-hole of a Beechjet. The ribbon cable was routed through the gasket on the baggage compartment door, taped to the side of the fuselage and brought into the cabin through the passenger entry door gasket. I sat in pressurized comfort watching for an intermittent that had plagued the airplane for months. It only occurred at altitude. Spotted the problem in the DAS data which led to discovery of a pushed back pin in a connector on the pressure bulkhead. Your task DOES have a practical solution that lies somewhere between the cheap-n-dirty to the high-altitude remote explorations cited. But you will have to build something. Bob . . . ________________________________________________________________________________
Subject: Re: Newbie with PM alternator feed question
From: "blues750" <den_beaulieu(at)yahoo.com>
Date: Oct 13, 2015
[quote="nuckolls.bob(at)aeroelect"] > > > > Trying to sort things out as I proceed and appreciate this forum and your literature! > > Pleased that you find it useful. I need to take > care of some other pressing business. I'll see if I > can sketch a diagram of what I've described above > and post it later today. > I've posted a drawing that describes on/off control of a 3-phase PM alternator with Over Voltage Protection http://tinyurl.com/n9tottf Bob, After doing a more detailed electrical load budget / requirements study, it looks like it will really be near the limits of the 30A rated PMA I currently have in my build. I am considering increasing the 30A PMA to a 50A PMA by changing to a 50A alternator stator the company has available. With that in mind, what do I need to do with the components on the drawing you provided earlier. Do I need to spec different relays or capacitor? Any other considerations? Your thoughts and insight will be much appreciated Thanks! Dave Bob . . . > [b] Read this topic online here: http://forums.matronics.com/viewtopic.php?p=447895#447895 ________________________________________________________________________________
Date: Oct 13, 2015
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Newbie with PM alternator feed question
> >Bob, > >After doing a more detailed electrical load budget / requirements >study, it looks like it will really be near the limits of the 30A >rated PMA I currently have in my build. I am considering increasing >the 30A PMA to a 50A PMA by changing to a 50A alternator stator the >company has available. With that in mind, what do I need to do with >the components on the drawing you provided earlier. Do I need to >spec different relays or capacitor? Any other considerations? Your >thoughts and insight will be much appreciated > >Thanks! A FIFTY amp PM alternator? Drops into the existing stator space? What rectifier/regulator do they recommend? Forgive my raside eyebrows . . . that's a BIG jump in performance . . . which is physically possible with bigger magnets, more iron, etc. But to make it a drop-in replacement raises some questions. Are there links to the company and to any data they offer for this 'upgrade'? Also, could you share your load analysis with us? It would be interesting to see how you've walled off the various requirements for the alternator-out failure mode. Bob . . . ________________________________________________________________________________
Date: Oct 13, 2015
From: Joe Dubner <jdubner(at)yahoo.com>
Subject: Re: Technique for DSub Pin / data breakout for RPM
issue plevyakh wrote, On 10/13/2015 08:01: >Can you please share a technique you've used to break into a DSub connector pin and read the data going through that Pin/Wire? Howard, A technique I use is to make up some short pairs of wires with D-subminiature pins like in the first attached image. The wires can be used to "bridge" a D-subminiature connector pair and at the same time allow connecting a test lead. http://www.mail2600.com/misc/D-subFixture1.jpg This technique gets old fast if the mating pair contains more than about four wires. :-( In that case, I use a fixture similar to the ones shown in the second image (but with more connectors). http://www.mail2600.com/misc/D-subFixture2.jpg The ribbon cable can have any reasonable number of D-sub connectors attached (they are easily crimped in a small vise). My favorite is to crimp on 5 connectors: a male and a female at each end and an additional connector for probing. This makes a universal breakout fixture and can also function as a temporary gender changer. -- Joe RV-8A Independence, OR ________________________________________________________________________________
Subject: US 240v to power EU 240v machine?
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Oct 18, 2015
During the lull in aerolectric posts... What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU machine uses a single hot leg, neutral and ground through the plug in the picture attached. Thanks, John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=448050#448050 Attachments: http://forums.matronics.com//files/dsc03159_small_173.jpg ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: John Tipton <jmtipton(at)btopenworld.com>
Date: Oct 18, 2015
That's not a EU plug, it's our standard 'ring main' plug here in the UK: the plug as you look at it (upside down) has three pins, the longest (at the bottom of the picture) is the earth, first to go into the socket when inserted and last to leave when removed, the pin on the left is the neutral, and the one on the right (as viewed) is the live and is fitted with a fuse up to 13amps ie: 3000watts (maximum load) divide by 240volts equals 12.5 (13amps) I presume you have similar 'wires' in USA ie: Live, Neutral and Earth John Sent from my iPad ----x--O--x---- > On 18 Oct 2015, at 07:45 pm, "jonlaury" wrote: > > > During the lull in aerolectric posts... > > What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU machine uses a single hot leg, neutral and ground through the plug in the picture attached. > > Thanks, > John > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=448050#448050 > > > > > Attachments: > > http://forums.matronics.com//files/dsc03159_small_173.jpg > > > > > > > ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: John Tipton <jmtipton(at)btopenworld.com>
Date: Oct 18, 2015
And just to make it clear: Earth lead is: green/yellow Live lead is: Brown Neutral lead is: Blue John Sent from my iPad ----x--O--x---- > On 18 Oct 2015, at 08:41 pm, John Tipton wrote: > > > That's not a EU plug, it's our standard 'ring main' plug here in the UK: the plug as you look at it (upside down) has three pins, the longest (at the bottom of the picture) is the earth, first to go into the socket when inserted and last to leave when removed, the pin on the left is the neutral, and the one on the right (as viewed) is the live and is fitted with a fuse up to 13amps ie: 3000watts (maximum load) divide by 240volts equals 12.5 (13amps) > > I presume you have similar 'wires' in USA ie: Live, Neutral and Earth > > John > > Sent from my iPad > > ----x--O--x---- > >> On 18 Oct 2015, at 07:45 pm, "jonlaury" wrote: >> >> >> During the lull in aerolectric posts... >> >> What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU machine uses a single hot leg, neutral and ground through the plug in the picture attached. >> >> Thanks, >> John >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=448050#448050 >> >> >> >> >> Attachments: >> >> http://forums.matronics.com//files/dsc03159_small_173.jpg > > > > > ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: Charlie England <ceengland7(at)gmail.com>
Date: Oct 18, 2015
> > >During the lull in aerolectric posts... > >What's the simplest way to use US 240v to power a EU 240v @ 150w >machine. The EU machine uses a single hot leg, neutral and ground >through the plug in the picture attached. > >Thanks, >John > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=448050#448050 > > >Attachments: > >http://forums.matronics.com//files/dsc03159_small_173.jpg > > One us leg (phase) to hot; other us leg to neutral....BUT....that may well leave some 'touchable' part of the device at 120-240 volts above ground potential, which could kill. Much safer to use a 120-240volt stepup transformer (pricey). -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ________________________________________________________________________________
From: "Bob McCallum" <robert.mccallum2(at)sympatico.ca>
Subject: US 240v to power EU 240v machine?
Date: Oct 18, 2015
The plug you've pictured is actually "British Standard" not EU, but simply connect your two North American 240 volt hot lines to the "line" and "neutral" of the British plug and ground to ground of course and you're good to go. (Ignore/don't connect, the North American neutral.) As someone else mentioned if this is a permanent conversion, cut off the British plug, attach a NEMA 6-15 North American plug http://tinyurl.com/nfrrzrx the matching receptacle such as this http://tinyurl.com/pags86c , and you're set. If you don't wish to modify the existing plug, here's the matching British receptacle. http://tinyurl.com/qcqqd9p By the way the British plugs are internally fused @ 13 Amps so the concern for connecting to a North American dryer or stove circuit is minimal as long as you retain the existing plug. (you can actually see the fuse in your photo) Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of jonlaury > Sent: Sunday, October 18, 2015 2:45 PM > To: aeroelectric-list(at)matronics.com > Subject: AeroElectric-List: US 240v to power EU 240v machine? > > > During the lull in aerolectric posts... > > What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU > machine uses a single hot leg, neutral and ground through the plug in the picture > attached. > > Thanks, > John > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=448050#448050 > > > > > Attachments: > > http://forums.matronics.com//files/dsc03159_small_173.jpg > > > > > _- > ===================================================== > ===== > _- > ===================================================== > ===== > _- > ===================================================== > ===== > _- > ===================================================== > ===== > > ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: Peter Pengilly <peter(at)sportingaero.com>
Date: Oct 18, 2015
Assuming you have a UK extension lead, fit a US 240v plug and hook it up. I lived in Texas for 5 years and did exactly that with several appliances - all seemed to work OK. Motors will run 20% faster as US uses 60Hz and UK/Europe uses 50Hz. When looks at the pins of the plug, hot is on the left (usually brown wire), earth is at the top (usually green or yellow/green wire) and neutral on the right (blue wire). The hot pin is usually protected by a fuse within the plug body. Peter PS US motors run in Europe can suffer from overheating. On 18/10/2015 19:45, jonlaury wrote: > > During the lull in aerolectric posts... > > What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU machine uses a single hot leg, neutral and ground through the plug in the picture attached. > > Thanks, > John > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=448050#448050 > > > Attachments: > > http://forums.matronics.com//files/dsc03159_small_173.jpg > > ________________________________________________________________________________
From: Mark Moyle <moylemc(at)gmail.com>
Subject: Re: US 240v to power EU 240v machine?
Date: Oct 18, 2015
http://www.amazon.com/STEP-UP-DOWN-TRANSFORMER-WATT/dp/B002RRPTZU/ref=sr_1_78?srs=2530188011&ie=UTF8&qid=1445199307&sr=8-78 Sent from my iPad > On Oct 18, 2015, at 10:45 AM, "jonlaury" wrote: > > > During the lull in aerolectric posts... > > What's the simplest way to use US 240v to power a EU 240v @ 150w machine. The EU machine uses a single hot leg, neutral and ground through the plug in the picture attached. > > Thanks, > John > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=448050#448050 > > > > > Attachments: > > http://forums.matronics.com//files/dsc03159_small_173.jpg > > > > > > > ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: Bill Putney <billp(at)wwpc.com>
Date: Oct 18, 2015
Ouch! So, in the U.S. on single phase services, the usual arrangement is 120V (L1) -neutral-120V (L2) and a separate protective ground that is tied to neutral at the load panel. A 240V to 240V isolation transformer can be used to make the connection you need. On the U.S. side, L1 and L2 are connected to the transformer's primary and on the U.K. side connect one leg of the transformer to neutral and one leg to 240V hot. Pass the protective ground through. If you connect the L1 and L2 of the U.S. system together you will make a lot of sparks and pop the circuit breaker! L1 and L2 are 2 120V legs 180 out of phase. Don't connect them! For just a 150W device I think you'll find an "International Step-up Transformer" is probably the simplest solution. Forget the U.S. 240V circuit all together. For $35 on Amazon I don't think you can buy all the connectors and stuff you need to build a solution for that price. http://www.amazon.com/Dynastar-Converter-Transformer-Lifetime-5-Year-Warranty/dp/B00KAJ8KG2/ref=sr_1_6?ie=UTF8&qid=1445203102&sr=8-6&keywords=international+transformer Bill On 10/18/15 13:09, Bob McCallum wrote: > > The plug you've pictured is actually "British Standard" not EU, but simply > connect your two North American 240 volt hot lines to the "line" and > "neutral" of the British plug and ground to ground of course and you're good > to go. (Ignore/don't connect, the North American neutral.) As someone else > mentioned if this is a permanent conversion, cut off the British plug, > attach a NEMA 6-15 North American plug http://tinyurl.com/nfrrzrx the > matching receptacle such as this http://tinyurl.com/pags86c , and you're > set. > > If you don't wish to modify the existing plug, here's the matching British > receptacle. http://tinyurl.com/qcqqd9p > By the way the British plugs are internally fused @ 13 Amps so the concern > for connecting to a North American dryer or stove circuit is minimal as long > as you retain the existing plug. (you can actually see the fuse in your > photo) > > Bob McC > >> -----Original Message----- >> From: owner-aeroelectric-list-server(at)matronics.com > [mailto:owner-aeroelectric-list- >> server(at)matronics.com] On Behalf Of jonlaury >> Sent: Sunday, October 18, 2015 2:45 PM >> To: aeroelectric-list(at)matronics.com >> Subject: AeroElectric-List: US 240v to power EU 240v machine? >> >> >> During the lull in aerolectric posts... >> >> What's the simplest way to use US 240v to power a EU 240v @ 150w machine. > The EU >> machine uses a single hot leg, neutral and ground through the plug in the > picture >> attached. >> >> Thanks, >> John >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=448050#448050 >> >> >> >> >> Attachments: >> >> http://forums.matronics.com//files/dsc03159_small_173.jpg >> >> >> >> >> _- >> ===================================================== >> ===== >> _- >> ===================================================== >> ===== >> _- >> ===================================================== >> ===== >> _- >> ===================================================== >> ===== >> >> > > ________________________________________________________________________________
From: "Bob McCallum" <robert.mccallum2(at)sympatico.ca>
Subject: US 240v to power EU 240v machine?
Date: Oct 18, 2015
The original question was for the "simplest" way to operate the UK device on a North American power system. The "Simplest" way is what I described. No transformer is required. A 240 volt device is a 240 volt device no matter which side of the ocean it resides on. In the UK (or Europe) 240 volt single phase devices are connected between a "hot" line and a "neutral" (grounded) line. In North America that same 240 volt single phase device would be connected between the two live line connections (L1, L2, as you've described) and not connected to the "neutral" (grounded) connection. In either case the actual "ground" (earth) connection would be made as usual. My original description in no way suggested connecting together the two "line" connections creating a direct short as you seem to have interpreted. Maybe I should have said "Connect your two North American 240 volt hot lines to the "line" and "neutral" RESPECTIVLY of the British plug and ground to ground of course and you're good to go" to make it clearer. If that British supply cord were cut open you would find a Brown conductor which you would connect to L1 of the North American system, a blue conductor which you would connect to L2, and a green/yellow striped conductor which you would connect to ground. (green or bare in the American system). The transformer connections you describe are correct and would work, but the transformer is not necessary. Simply connect directly to the 240 lines plus ground. The only slight difference, as someone else pointed out, is frequency, which in North America is 60 Hertz and most of the rest of the planet 50 hertz. This will make a difference in the speed of motors which will be faster on 60 and slower on 50. Also depending on the iron content 60 cycle motors may tend to overheat on 50 cycle. Respectfully Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of Bill Putney > Sent: Sunday, October 18, 2015 5:22 PM > To: aeroelectric-list(at)matronics.com > Subject: Re: AeroElectric-List: US 240v to power EU 240v machine? > > > Ouch! So, in the U.S. on single phase services, the usual arrangement is > 120V (L1) -neutral-120V (L2) and a separate protective ground that is > tied to neutral at the load panel. A 240V to 240V isolation transformer > can be used to make the connection you need. On the U.S. side, L1 and L2 > are connected to the transformer's primary and on the U.K. side connect > one leg of the transformer to neutral and one leg to 240V hot. Pass the > protective ground through. > > If you connect the L1 and L2 of the U.S. system together you will make a > lot of sparks and pop the circuit breaker! L1 and L2 are 2 120V legs > 180 out of phase. Don't connect them! > > For just a 150W device I think you'll find an "International Step-up > Transformer" is probably the simplest solution. Forget the U.S. 240V > circuit all together. For $35 on Amazon I don't think you can buy all > the connectors and stuff you need to build a solution for that price. > > http://www.amazon.com/Dynastar-Converter-Transformer-Lifetime-5-Year- > Warranty/dp/B00KAJ8KG2/ref=sr_1_6?ie=UTF8&qid=1445203102&sr=8- > 6&keywords=international+transformer > > > Bill > > On 10/18/15 13:09, Bob McCallum wrote: > > > > > The plug you've pictured is actually "British Standard" not EU, but simply > > connect your two North American 240 volt hot lines to the "line" and > > "neutral" of the British plug and ground to ground of course and you're good > > to go. (Ignore/don't connect, the North American neutral.) As someone else > > mentioned if this is a permanent conversion, cut off the British plug, > > attach a NEMA 6-15 North American plug http://tinyurl.com/nfrrzrx the > > matching receptacle such as this http://tinyurl.com/pags86c , and you're > > set. > > > > If you don't wish to modify the existing plug, here's the matching British > > receptacle. http://tinyurl.com/qcqqd9p > > By the way the British plugs are internally fused @ 13 Amps so the concern > > for connecting to a North American dryer or stove circuit is minimal as long > > as you retain the existing plug. (you can actually see the fuse in your > > photo) > > > > Bob McC > > > >> -----Original Message----- > >> From: owner-aeroelectric-list-server(at)matronics.com > > [mailto:owner-aeroelectric-list- > >> server(at)matronics.com] On Behalf Of jonlaury > >> Sent: Sunday, October 18, 2015 2:45 PM > >> To: aeroelectric-list(at)matronics.com > >> Subject: AeroElectric-List: US 240v to power EU 240v machine? > >> > >> > >> During the lull in aerolectric posts... > >> > >> What's the simplest way to use US 240v to power a EU 240v @ 150w machine. > > The EU > >> machine uses a single hot leg, neutral and ground through the plug in the > > picture > >> attached. > >> > >> Thanks, > >> John > >> > >> > >> > >> > >> Read this topic online here: > >> > >> http://forums.matronics.com/viewtopic.php?p=448050#448050 > >> > >> > >> > >> > >> Attachments: > >> > >> http://forums.matronics.com//files/dsc03159_small_173.jpg > >> > >> > >> > >> > >> _- > >> > ===================================================== > >> ===== > >> _- > >> > ===================================================== > >> ===== > >> _- > >> > ===================================================== > >> ===== > >> _- > >> > ===================================================== > >> ===== > >> > >> > > > > > > > > > > > > > _- > ===================================================== > ===== > _- > ===================================================== > ===== > _- > ===================================================== > ===== > _- > ===================================================== > ===== > > ________________________________________________________________________________
Date: Oct 18, 2015
Subject: Re: US 240v to power EU 240v machine?
From: Paul Kuntz <paul.r.kuntz(at)gmail.com>
Bob McC is correct. I was on assignment to the UK for a few years, and took a 240V US power tool with me to the UK, then brought a couple of 240V UK power tools back with me when the assignment ended. The only thing I had to do at each end of the assignment was cut off the plugs and replace them. There are also plug adapters available from many sources if you don't want to replace the plugs. As Bob notes, since they were powered by synchronous AC motors, they ran faster on 60 Hz US power than they did on 50 Hz electric power. That's almost never a problem, unless the application is dependent on the motor speed, such as an electric clock. Paul Kuntz On Sun, Oct 18, 2015 at 3:53 PM, Bob McCallum wrote: > robert.mccallum2(at)sympatico.ca> > > The original question was for the "simplest" way to operate the UK device > on > a North American power system. The "Simplest" way is what I described. No > transformer is required. A 240 volt device is a 240 volt device no matter > which side of the ocean it resides on. In the UK (or Europe) 240 volt > single > phase devices are connected between a "hot" line and a "neutral" (grounde d) > line. In North America that same 240 volt single phase device would be > connected between the two live line connections (L1, L2, as you've > described) and not connected to the "neutral" (grounded) connection. In > either case the actual "ground" (earth) connection would be made as usual . > > My original description in no way suggested connecting together the two > "line" connections creating a direct short as you seem to have interprete d. > Maybe I should have said "Connect your two North American 240 volt hot > lines > to the "line" and > "neutral" RESPECTIVLY of the British plug and ground to ground of course > and > you're good > to go" to make it clearer. > > If that British supply cord were cut open you would find a Brown conducto r > which you would connect to L1 of the North American system, a blue > conductor > which you would connect to L2, and a green/yellow striped conductor which > you would connect to ground. (green or bare in the American system). > > The transformer connections you describe are correct and would work, but > the > transformer is not necessary. Simply connect directly to the 240 lines pl us > ground. > > The only slight difference, as someone else pointed out, is frequency, > which > in North America is 60 Hertz and most of the rest of the planet 50 hertz. > This will make a difference in the speed of motors which will be faster o n > 60 and slower on 50. Also depending on the iron content 60 cycle motors m ay > tend to overheat on 50 cycle. > > Respectfully > Bob McC > > > -----Original Message----- > > From: owner-aeroelectric-list-server(at)matronics.com > [mailto:owner-aeroelectric-list- > > server(at)matronics.com] On Behalf Of Bill Putney > > Sent: Sunday, October 18, 2015 5:22 PM > > To: aeroelectric-list(at)matronics.com > > Subject: Re: AeroElectric-List: US 240v to power EU 240v machine? > > > > > > Ouch! So, in the U.S. on single phase services, the usual arrangement i s > > 120V (L1) -neutral-120V (L2) and a separate protective ground that is > > tied to neutral at the load panel. A 240V to 240V isolation transformer > > can be used to make the connection you need. On the U.S. side, L1 and L 2 > > are connected to the transformer's primary and on the U.K. side connect > > one leg of the transformer to neutral and one leg to 240V hot. Pass the > > protective ground through. > > > > If you connect the L1 and L2 of the U.S. system together you will make a > > lot of sparks and pop the circuit breaker! L1 and L2 are 2 120V legs > > 180=C2=BA out of phase. Don't connect them! > > > > For just a 150W device I think you'll find an "International Step-up > > Transformer" is probably the simplest solution. Forget the U.S. 240V > > circuit all together. For $35 on Amazon I don't think you can buy all > > the connectors and stuff you need to build a solution for that price. > > > > http://www.amazon.com/Dynastar-Converter-Transformer-Lifetime-5-Year- > > Warranty/dp/B00KAJ8KG2/ref=sr_1_6?ie=UTF8&qid=1445203102&sr=8- > > 6&keywords=international+transformer > > > > > > Bill > > > > On 10/18/15 13:09, Bob McCallum wrote: > > > > > > > > The plug you've pictured is actually "British Standard" not EU, but > simply > > > connect your two North American 240 volt hot lines to the "line" and > > > "neutral" of the British plug and ground to ground of course and you' re > good > > > to go. (Ignore/don't connect, the North American neutral.) As someone > else > > > mentioned if this is a permanent conversion, cut off the British plug , > > > attach a NEMA 6-15 North American plug http://tinyurl.com/nfrrzrx > the > > > matching receptacle such as this http://tinyurl.com/pags86c , and > you're > > > set. > > > > > > If you don't wish to modify the existing plug, here's the matching > British > > > receptacle. http://tinyurl.com/qcqqd9p > > > By the way the British plugs are internally fused @ 13 Amps so the > concern > > > for connecting to a North American dryer or stove circuit is minimal as > long > > > as you retain the existing plug. (you can actually see the fuse in yo ur > > > photo) > > > > > > Bob McC > > > > > >> -----Original Message----- > > >> From: owner-aeroelectric-list-server(at)matronics.com > > > [mailto:owner-aeroelectric-list- > > >> server(at)matronics.com] On Behalf Of jonlaury > > >> Sent: Sunday, October 18, 2015 2:45 PM > > >> To: aeroelectric-list(at)matronics.com > > >> Subject: AeroElectric-List: US 240v to power EU 240v machine? > > >> > > > >> > > >> During the lull in aerolectric posts... > > >> > > >> What's the simplest way to use US 240v to power a EU 240v @ 150w > machine. > > > The EU > > >> machine uses a single hot leg, neutral and ground through the plug i n > the > > > picture > > >> attached. > > >> > > >> Thanks, > > >> John > > >> > > >> > > >> > > >> > > >> Read this topic online here: > > >> > > >> http://forums.matronics.com/viewtopic.php?p=448050#448050 > > >> > > >> > > >> > > >> > > >> Attachments: > > >> > > >> http://forums.matronics.com//files/dsc03159_small_173.jpg > > >> > > >> > > >> > > >> > > >> _- > > >> > > ======================= ===== > > >> ===== > > >> _- > > >> > > ======================= ===== > > >> ===== > > >> _- > > >> > > ======================= ===== > > >> ===== > > >> _- > > >> > > ======================= ===== > > >> ===== > > >> > > >> > > > > > > > > > > > > > > > > > > > > > _- > > ======================= ===== > > ===== > > _- > > ======================= ===== > > ===== > > _- > > ======================= ===== > > ===== > > _- > > ======================= ===== > > ===== > > > > > > =========== =========== =========== =========== > > ________________________________________________________________________________
Subject: Re: US 240v to power EU 240v machine?
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Oct 19, 2015
WOW! >From the response to my rather pedestrian dilemma, and with no competing posts, it sounds like there's a bunch of Aerolectric List junkies needing a fix ! :D Big THANKS! to all. John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=448087#448087 ________________________________________________________________________________
From: <rnjcurtis(at)charter.net>
Subject: Re: Q?Re:_AeroElectric-List:_Re:_US_240v_to_power_EU_240v_machine=3F?
Date: Oct 19, 2015
DQoNCg0KDQoNCg0KV09XIQ0KPkZyb20gdGhlIHJlc3BvbnNlIHRvIG15IHJhdGhlciBwZWRlc3Ry aWFuIGRpbGVtbWEsIGFuZCB3aXRoIG5vIGNvbXBldGluZyBwb3N0cywgaXQgc291bmRzIGxpa2Ug dGhlcmUncyBhIGJ1bmNoIG9mIEFlcm9sZWN0cmljIExpc3QganVua2llcyBuZWVkaW5nIGEgZml4 ICEgOkQNCkJpZyBUSEFOS1MhIHRvIGFsbC4NCg0KDQoNCg0KDQoNCk5PISAgSnVzdCBzb21lIG1p c3VuZGVyc3RhbmRpbmdzIHRoYXQgbmVlZGVkIHRvIGJlIGNsZWFyZWQgdXAsIGFuZCB3YXMgZG9u ZS4NCg0KDQpSb2dlcg= ________________________________________________________________________________
From: Dennis A Glaeser <dennis.glaeser(at)gm.com>
Subject: Bouncing ammeter question


August 19, 2015 - October 19, 2015

AeroElectric-Archive.digest.vol-mw