---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 05/14/07: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:22 AM - Re: Nuckolls is bailing out of the OEM airframe business (Steve Thomas) 2. 08:36 AM - Re: Nuckolls is bailing out of the OEM airframe business (Robert L. Nuckolls, III) 3. 09:04 AM - Re: Nuckolls is bailing out of the OEM airframe business (Robert L. Nuckolls, III) 4. 10:41 AM - Instrument Cluster Ground Wires (Michael Hinchcliff) 5. 11:09 AM - Re: Instrument Cluster Ground Wires (Bill Steer) 6. 11:42 AM - Re: Instrument Cluster Ground Wires (Hinde, Frank George (Corvallis)) 7. 02:28 PM - Re: Instrument Cluster Ground Wires (Peter Harris) 8. 03:35 PM - Re: Instrument Cluster Ground Wires (Robert L. Nuckolls, III) 9. 05:31 PM - Re: Instrument Cluster Ground Wires (Michael Hinchcliff) 10. 06:09 PM - Re: Nuckolls is bailing out of the OEM airframe businessNuckolls is bailing out of the OEM airframe (Todd Heffley) 11. 07:30 PM - Avionics Master (Greg Vouga) 12. 08:41 PM - Connetor Shells-Loctite (DEAN PSIROPOULOS) 13. 08:57 PM - Re: Avionics Master (Robert L. Nuckolls, III) 14. 08:57 PM - Re: Connetor Shells-Loctite (Bob White) 15. 09:06 PM - Re: Re: Battery Capacity Check (Robert L. Nuckolls, III) 16. 09:19 PM - Re: Avionics Master (B Tomm) 17. 10:24 PM - Re: Connetor Shells-Loctite (Jim Jewell) 18. 10:45 PM - Re: Avionics Master (Michel Creek) ________________________________ Message 1 _____________________________________ Time: 07:22:15 AM PST US From: Steve Thomas Subject: Re: AeroElectric-List: Nuckolls is bailing out of the OEM airframe business Congratulations Bob! There is nothing like stimulating the creative mind by doing something new. Best of luck in your new adventure. Best Regards, Steve ____________________________________________________________________ On May 13, 2007, at 10:32 PM, Robert L. Nuckolls, III wrote: > I just e-mailed the necessary folks at Hawker-Beechcraft that I'm > retiring from that activity after 13 years and 10 days. They're > just not doing any real EE design work any more. > > I'll be joining forces with a gray-matter consortium here in > Wichita. We've already got a firm request and a couple of tentative > inquiries about developing the best we know how to do in flap and > pitch trim actuation systems. This is going to be fun! > > > Bob . . . ________________________________ Message 2 _____________________________________ Time: 08:36:50 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Nuckolls is bailing out of the OEM airframe business > > >Bob, > >Who is doing the real EE work for Hawker-Beechcraft? Essentially nobody. The "new order" is to farm out as much new development as possible. This makes sense to individuals who's business model is to fabricate from existing technologies . . . the Legos-TinkerToy approach. Problem is, that folks expected to understand what goes out in our airplanes are isolated from the innards so completely that trying to be a Subject Matter Expert on any one system is exceedingly difficult if not impossible to do. >Congrats on your new job. I'm sure you will love it. It's an extension of work I've been doing as a hobby that makes a little money for over 40 years. It's always been fun . . . when it stops being fun, I'll go find something else to do. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 3 _____________________________________ Time: 09:04:09 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Nuckolls is bailing out of the OEM airframe business At 09:43 PM 5/13/2007 -0700, you wrote: > >As a start-up? Not really . . . it's an extension of an activty that's been going on for about 30 years. We're just formalizing it and hanging out the shingle. Bob . . . ________________________________ Message 4 _____________________________________ Time: 10:41:30 AM PST US From: "Michael Hinchcliff" Subject: AeroElectric-List: Instrument Cluster Ground Wires Perhaps I'm over-thinking a very simple problem. I have a modular instrument cluster from Mitchell Aircraft products. Each modular instrument has its own ground and return line, as well as wires for the lighting circuits. The wires for each instrument are 20 AWG and about a foot long, however, I need them to be longer to reach the B&C tabbed ground block that will be mounted on the inside of the firewall. I see two options for resolving this problem: Option 1: Solder or crimp all of the ground wires together as they are and then use a larger wire to complete the necessary distance to the ground tab. -Would it be advisable to even attempt to bring as many as 10 wires together at one point? Option 2: Extend the length of each 20 AWG wire so that each one can reach the ground tab individually. Again, the question stands: Is it unreasonable to solder or crimp up to 10 ground wires together at the end or should I plan to crimp a fast-on connector to each individual wire? If the latter, than I will need to upgrade my 24 tab block to the 48 tab. (Would seem like a lot of tabs for one device, however.) Let me know if you have another idea I should consider. Thanks in advance for the input. Michael H. ________________________________ Message 5 _____________________________________ Time: 11:09:19 AM PST US From: Bill Steer Subject: Re: AeroElectric-List: Instrument Cluster Ground Wires If you have a metal airframe, why couldn't you ground them locally? Bill Michael Hinchcliff wrote: > > Perhaps Im over-thinking a very simple problem. I have a modular > instrument cluster from Mitchell Aircraft products. Each modular > instrument has its own ground and return line, as well as wires for > the lighting circuits. The wires for each instrument are 20 AWG and > about a foot long, however, I need them to be longer to reach the B&C > tabbed ground block that will be mounted on the inside of the > firewall. I see two options for resolving this problem: > > Option 1: Solder or crimp all of the ground wires together as they are > and then use a larger wire to complete the necessary distance to the > ground tab. Would it be advisable to even attempt to bring as many as > 10 wires together at one point? > > Option 2: Extend the length of each 20 AWG wire so that each one can > reach the ground tab individually. Again, the question stands: Is it > unreasonable to solder or crimp up to 10 ground wires together at the > end or should I plan to crimp a fast-on connector to each individual > wire? If the latter, than I will need to upgrade my 24 tab block to > the 48 tab. (Would seem like a lot of tabs for one device, however.) > > Let me know if you have another idea I should consider. > ________________________________ Message 6 _____________________________________ Time: 11:42:15 AM PST US Subject: RE: AeroElectric-List: Instrument Cluster Ground Wires From: "Hinde, Frank George (Corvallis)" I would extend them and ground them to the block...Its only 10 wires or so its not like its that many extra crimps... I would avoid joining to a thick wire as it maybe difficult to get a good joint unless you solder them all together. Frank ________________________________ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Michael Hinchcliff Sent: Monday, May 14, 2007 10:40 AM Subject: AeroElectric-List: Instrument Cluster Ground Wires Perhaps I'm over-thinking a very simple problem. I have a modular instrument cluster from Mitchell Aircraft products. Each modular instrument has its own ground and return line, as well as wires for the lighting circuits. The wires for each instrument are 20 AWG and about a foot long, however, I need them to be longer to reach the B&C tabbed ground block that will be mounted on the inside of the firewall. I see two options for resolving this problem: Option 1: Solder or crimp all of the ground wires together as they are and then use a larger wire to complete the necessary distance to the ground tab. -Would it be advisable to even attempt to bring as many as 10 wires together at one point? Option 2: Extend the length of each 20 AWG wire so that each one can reach the ground tab individually. Again, the question stands: Is it unreasonable to solder or crimp up to 10 ground wires together at the end or should I plan to crimp a fast-on connector to each individual wire? If the latter, than I will need to upgrade my 24 tab block to the 48 tab. (Would seem like a lot of tabs for one device, however.) Let me know if you have another idea I should consider. Thanks in advance for the input. Michael H. ________________________________ Message 7 _____________________________________ Time: 02:28:34 PM PST US From: "Peter Harris" Subject: RE: AeroElectric-List: Instrument Cluster Ground Wires I made two ground collectors from alum angle then ran a single ground from each to the block. Peter H _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Hinde, Frank George (Corvallis) Sent: Tuesday, 15 May 2007 4:39 AM Subject: RE: AeroElectric-List: Instrument Cluster Ground Wires I would extend them and ground them to the block...Its only 10 wires or so its not like its that many extra crimps... I would avoid joining to a thick wire as it maybe difficult to get a good joint unless you solder them all together. Frank _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Michael Hinchcliff Sent: Monday, May 14, 2007 10:40 AM Subject: AeroElectric-List: Instrument Cluster Ground Wires Perhaps I'm over-thinking a very simple problem. I have a modular instrument cluster from Mitchell Aircraft products. Each modular instrument has its own ground and return line, as well as wires for the lighting circuits. The wires for each instrument are 20 AWG and about a foot long, however, I need them to be longer to reach the B&C tabbed ground block that will be mounted on the inside of the firewall. I see two options for resolving this problem: Option 1: Solder or crimp all of the ground wires together as they are and then use a larger wire to complete the necessary distance to the ground tab. -Would it be advisable to even attempt to bring as many as 10 wires together at one point? Option 2: Extend the length of each 20 AWG wire so that each one can reach the ground tab individually. Again, the question stands: Is it unreasonable to solder or crimp up to 10 ground wires together at the end or should I plan to crimp a fast-on connector to each individual wire? If the latter, than I will need to upgrade my 24 tab block to the 48 tab. (Would seem like a lot of tabs for one device, however.) Let me know if you have another idea I should consider. Thanks in advance for the input. Michael H. href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.matro nics.com/Navigator?AeroElectric-List href="http://forums.matronics.com">http://forums.matronics.com ________________________________ Message 8 _____________________________________ Time: 03:35:47 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Instrument Cluster Ground Wires At 12:39 PM 5/14/2007 -0500, you wrote: >Perhaps Im over-thinking a very simple problem. I have a modular >instrument cluster from Mitchell Aircraft products. Each modular >instrument has its own ground and return line, as well as wires for the >lighting circuits. The wires for each instrument are 20 AWG and about a >foot long, however, I need them to be longer to reach the B&C tabbed >ground block that will be mounted on the inside of the firewall. I see >two options for resolving this problem: > > > >Option 1: Solder or crimp all of the ground wires together as they are and >then use a larger wire to complete the necessary distance to the ground >tab. Would it be advisable to even attempt to bring as many as 10 wires >together at one point? > > >Option 2: Extend the length of each 20 AWG wire so that each one can reach >the ground tab individually. Again, the question stands: Is it >unreasonable to solder or crimp up to 10 ground wires together at the end >or should I plan to crimp a fast-on connector to each individual wire? If >the latter, than I will need to upgrade my 24 tab block to the 48 >tab. (Would seem like a lot of tabs for one device, however.) > > >Let me know if you have another idea I should consider. See http://www.aeroelectric.com/Pictures/Grounding/Minibus1.jpg http://www.aeroelectric.com/Pictures/Grounding/Minibus2.jpg http://www.aeroelectric.com/Pictures/Grounding/AVG_RA.jpg http://www.aeroelectric.com/Pictures/Grounding/AGB_V.jpg http://www.aeroelectric.com/Pictures/Grounding/Avionics_Bus_3.jpg Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 9 _____________________________________ Time: 05:31:23 PM PST US From: "Michael Hinchcliff" Subject: Re: AeroElectric-List: Instrument Cluster Ground Wires Good approach. Thanks, Bob. Do not archive. ----- Original Message ----- From: "Robert L. Nuckolls, III" Sent: Monday, May 14, 2007 6:35 PM Subject: Re: AeroElectric-List: Instrument Cluster Ground Wires > > > At 12:39 PM 5/14/2007 -0500, you wrote: > >>Perhaps I'm over-thinking a very simple problem. I have a modular >>instrument cluster from Mitchell Aircraft products. Each modular >>instrument has its own ground and return line, as well as wires for the >>lighting circuits. The wires for each instrument are 20 AWG and about a >>foot long, however, I need them to be longer to reach the B&C tabbed >>ground block that will be mounted on the inside of the firewall. I see >>two options for resolving this problem: >> >>>/> >> >>Option 1: Solder or crimp all of the ground wires together as they are and >>then use a larger wire to complete the necessary distance to the ground >>tab. -Would it be advisable to even attempt to bring as many as 10 wires >>together at one point? >> >> >> >>Option 2: Extend the length of each 20 AWG wire so that each one can reach >>the ground tab individually. Again, the question stands: Is it >>unreasonable to solder or crimp up to 10 ground wires together at the end >>or should I plan to crimp a fast-on connector to each individual wire? If >>the latter, than I will need to upgrade my 24 tab block to the 48 tab. >>(Would seem like a lot of tabs for one device, however.) >> >> >> >>Let me know if you have another idea I should consider. > > See > > http://www.aeroelectric.com/Pictures/Grounding/Minibus1.jpg > > http://www.aeroelectric.com/Pictures/Grounding/Minibus2.jpg > > http://www.aeroelectric.com/Pictures/Grounding/AVG_RA.jpg > > http://www.aeroelectric.com/Pictures/Grounding/AGB_V.jpg > > http://www.aeroelectric.com/Pictures/Grounding/Avionics_Bus_3.jpg > > > Bob . . . > > ---------------------------------------- > ( "Physics is like sex: sure, it may ) > ( give some practical results, but ) > ( that's not why we do it." ) > ( ) > ( Richard P. Feynman ) > ---------------------------------------- > > > ________________________________ Message 10 ____________________________________ Time: 06:09:54 PM PST US From: Todd Heffley Subject: Re: AeroElectric-List: Nuckolls is bailing out of the OEM airframe businessNuckolls is bailing out of the OEM airframe Congratulations, I could tell from you posts you were an eagle waddling in a prairie dog town. Todd ________________________________ Message 11 ____________________________________ Time: 07:30:08 PM PST US From: "Greg Vouga" Subject: AeroElectric-List: Avionics Master All, I'm working on my panel and I'm trying to decide if I should put an Avionics Master switch. In my experience with rental planes this was nice to have since there was one switch to turn everything on or off during engine start or shutdown. Is there any reason not to add this feature? I'm planning an E-Bus and Main Bus configuration similar to the Z-13/8 design. Thanks _________________________________________________________________ Make every IM count. Download Messenger and join the im Initiative now. Its free. http://im.live.com/messenger/im/home/?source=TAGHM_MAY07 ________________________________ Message 12 ____________________________________ Time: 08:41:37 PM PST US From: "DEAN PSIROPOULOS" Subject: AeroElectric-List: Connetor Shells-Loctite Question on keeping the screws and nuts from coming apart on the DB-25 and computer style connector shells and wire clamps. I tried some blue locktite and it seemed to work fine but I was wondering if Locktite is needed or if just installing the screws and nuts dry (but tight) is sufficient? Seems trivial but I don't want the hardware coming apart and falling into my lap while I'm flying (and I don't want to have to crawl up behind the panel to put things back together once the airplane is finished). Also, following Bob's tenet of not using wire smaller than AWG-22 has left me with some large bundles coming out of the DB-25 connectors, especially on the back of the VOR/ILS indicator and the Dynon EFIS. I couldn't use the supplied bundle clamp/strain reliever because the bundle was too large so I ended up using half the clamp and a tie wrap through the two screw holes for strain relief. I wrapped some vinyl tape around the bundle at that point to stave off chaffing the Tefzel insulation of the bundle. Seems kind of kludgey to me though, any words of wisdom on good ways to protect the bundles inside the connectors while providing decent strain relief? Thanks. Dean Psiropoulos RV-6A N197DM Installing radio harnesses ________________________________ Message 13 ____________________________________ Time: 08:57:08 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Avionics Master At 07:28 PM 5/14/2007 -0700, you wrote: > >All, > >I'm working on my panel and I'm trying to decide if I should put an >Avionics Master switch. In my experience with rental planes this was nice >to have since there was one switch to turn everything on or off during >engine start or shutdown. > >Is there any reason not to add this feature? I'm planning an E-Bus and >Main Bus configuration similar to the Z-13/8 design. Why "similar to"? What feature do you find missing or performance goal that has gone lacking. Goto http://aeroelectric.com . . . and put 'avionics master' in the search box. After reviewing the discussions, help us out by citing where you perceive a return on investment for having the feature. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 14 ____________________________________ Time: 08:57:33 PM PST US From: Bob White Subject: Re: AeroElectric-List: Connetor Shells-Loctite Hi Dean, I've never used anything on the threads and I've never seen one come apart. What I've found to work really well for the strain relief is to wrap the cable where it exits the backshell with silicone fusion tape until it's slightly larger than the hole. Then tighten the backshell over it. It make a snug fit and protects the wires at the same time. The tape turns into a solid plug but it's easily cut away if you need to work on it later. Bob W. On Mon, 14 May 2007 23:40:00 -0400 "DEAN PSIROPOULOS" wrote: > > Question on keeping the screws and nuts from coming apart on the DB-25 and > computer style connector shells and wire clamps. I tried some blue locktite > and it seemed to work fine but I was wondering if Locktite is needed or if > just installing the screws and nuts dry (but tight) is sufficient? Seems > trivial but I don't want the hardware coming apart and falling into my lap > while I'm flying (and I don't want to have to crawl up behind the panel to > put things back together once the airplane is finished). > > Also, following Bob's tenet of not using wire smaller than AWG-22 has left > me with some large bundles coming out of the DB-25 connectors, especially on > the back of the VOR/ILS indicator and the Dynon EFIS. I couldn't use the > supplied bundle clamp/strain reliever because the bundle was too large so I > ended up using half the clamp and a tie wrap through the two screw holes for > strain relief. I wrapped some vinyl tape around the bundle at that point to > stave off chaffing the Tefzel insulation of the bundle. Seems kind of > kludgey to me though, any words of wisdom on good ways to protect the > bundles inside the connectors while providing decent strain relief? Thanks. > > Dean Psiropoulos > RV-6A N197DM > Installing radio harnesses > > > > > > > -- N93BD - Rotary Powered BD-4 - http://www.bob-white.com 3.8 Hours Total Time and holding Cables for your rotary installation - http://www.roblinphoto.com/shop/ ________________________________ Message 15 ____________________________________ Time: 09:06:53 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Battery Capacity Check At 07:33 PM 5/13/2007 -0700, you wrote: >At 05:11 5/13/2007, you wrote: >> >>Your B&C alternator delivers 12V x 60A = 720W of electricity at maximum >>rating. Assuming (big assumption) that the alternator is about 75% >>efficient, that would be about 1KW or 1.3 HP of energy taken from the >>engines output. You can apply the same formula to the pump-pad driven version. >> >>Rob > >Good stuff Rob, you beat me to it. >For those not wanting to do the math, 746 watts equals 1 HP. >I might quibble that the B&C, or any other charging device, actually >delivers closer to 14 volts and for a 60A output is closer to 840W output, >but that's a minor nit. > >What all this talk did was finally prod me into doing a load and endurance >test of a Concorde RG-35AXC, new in October 2006. From calculations and >actual measurements we've determined our "normal" load is about 37 amps, >and after load shedding to "essential" equipment it drops to ~11 or 12 >amps. All the essential equipment installed is rated to 10.0 volts minimum. > >The first test was per the ICAW, as nearly as I could replicate without a >constant current load. >The second test assumed an alternator failure at time zero with a fully >charged battery. We have a JPI EDM-800 installed with the bus voltage >alarm set point at 12.0 volts and tested it will annunciate at that >voltage. At 20 minutes (+/- one minute) into the test we reached 12.0 >volts and shed to essential at ~12.5 amps. Again, not having a constant >current load, adjustments were necessiated during the test. However this >time they were to maintain constant load power, as newer avionics will >increase their current draw with decreasing supply voltage. Here I've >tried to maintain ~140 to 150 watts. Note the adjustments at 1:00, 2:00, >2:30 and 2:45 into the test. > >It was a pleasant surprise to find we have better than two hours endurance! >That battery delivered over 2.5kW/Hr of power. > >Pics of the test setup and raw data upon request. > >Ron Q. GOOD WORK! A very learned gentleman once noted . . . "When you can measure what you are speaking about and express it in numbers, you know something about it." Lord William Thomson Kelvin (1824-1907) See: http://sse.jpl.nasa.gov/scitech/display.cfm?ST_ID=330 You now have a benchmark by which you can craft your Plan-B ritual for dealing with an alternator-out situation . . . assuming of course that you've also initated a plan for tracking the battery's abilty to support Plan-B. Thanks for sharing this with us . . . Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 16 ____________________________________ Time: 09:19:45 PM PST US From: "B Tomm" Subject: RE: AeroElectric-List: Avionics Master Greg, It's been discussed several times and as I recall, the reason to not do it is a) theoretical single point of failure, and b) no real good reason to do it. Bevan RV7A Wiring and misc panel work -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Greg Vouga Sent: Monday, May 14, 2007 7:28 PM Subject: AeroElectric-List: Avionics Master --> All, I'm working on my panel and I'm trying to decide if I should put an Avionics Master switch. In my experience with rental planes this was nice to have since there was one switch to turn everything on or off during engine start or shutdown. Is there any reason not to add this feature? I'm planning an E-Bus and Main Bus configuration similar to the Z-13/8 design. Thanks _________________________________________________________________ Make every IM count. Download Messenger and join the i'm Initiative now. It's free. http://im.live.com/messenger/im/home/?source=TAGHM_MAY07 ________________________________ Message 17 ____________________________________ Time: 10:24:50 PM PST US From: "Jim Jewell" Subject: Re: AeroElectric-List: Connetor Shells-Loctite Hi Dean, As for securing DB connectors: Due to vibration the engine DB 9 connector for the Lightspeed EI hall effect unit was one place that I felt needed to be secured beyond just dry tightening the screws. I thought Locktite might make removal for servicing a headache. After tightening the screws I used .016 safety wire laid over the screw slots and then twisted tight. This aproach of course would only be useful in areas where there is room for relatively easy physical access. Build on, Jim Jewell in Kelowna - RV6A 10 plus hr. into the flight testing ----- Original Message ----- From: "DEAN PSIROPOULOS" Sent: Monday, May 14, 2007 8:40 PM Subject: AeroElectric-List: Connetor Shells-Loctite > > > Question on keeping the screws and nuts from coming apart on the DB-25 and > computer style connector shells and wire clamps. I tried some blue > locktite > and it seemed to work fine but I was wondering if Locktite is needed or if > just installing the screws and nuts dry (but tight) is sufficient? Seems > trivial but I don't want the hardware coming apart and falling into my lap > while I'm flying (and I don't want to have to crawl up behind the panel to > put things back together once the airplane is finished). > > Also, following Bob's tenet of not using wire smaller than AWG-22 has left > me with some large bundles coming out of the DB-25 connectors, especially > on > the back of the VOR/ILS indicator and the Dynon EFIS. I couldn't use the > supplied bundle clamp/strain reliever because the bundle was too large so > I > ended up using half the clamp and a tie wrap through the two screw holes > for > strain relief. I wrapped some vinyl tape around the bundle at that point > to > stave off chaffing the Tefzel insulation of the bundle. Seems kind of > kludgey to me though, any words of wisdom on good ways to protect the > bundles inside the connectors while providing decent strain relief? > Thanks. > > Dean Psiropoulos > RV-6A N197DM > Installing radio harnesses > > > ________________________________ Message 18 ____________________________________ Time: 10:45:39 PM PST US From: "Michel Creek" Subject: RE: AeroElectric-List: Avionics Master This is an excerpt from the GRT install manual referring to the use of an avionics master (at least that is what I read into it). Perhaps Bob can clear this up as it is somewhat ambiguous. Power Connections The display units each include 2 isolated power input connections. This allows redundant power sources, such as a main and secondary bus. The display units consume approximately 1 amp, making even a small 3 Amp-Hour gel cell a suitable emergency source. The configuration of the power supplied to the display unit(s) is left to the installer. Considerations such as the number of power buses, the desire or not to supply one pieceof equipment with power from redundant buses (which in theory allows the possibility of one device affecting both buses), the configuration of the electrical system with respect to backup equipment, and so on, may dictate the best configuration for a particular airplane. No provision is included within the display units for a power switch. If a power switch is desired for the EFIS, the +12V power should be controlled with the switch (not ground). The display units include internal thermally-activated fuses. This protects the equipment from internal electrical faults. Power supplied to the EFIS must pass through a fuse or 4 circuit breaker or fuse. It should be sized to allow at least 1.5 amps per display unit, with a maximum rating of 5 amps. The AHRS and display units monitor all of their power inputs, and alarms are available to annunciate the loss of any power source that was provided and is expected to be working according to the "General Setup" menu. The majority of the current flow into the display unit will occur on the bus with thehighest voltage. It is desirable to have the display units and AHRS off during the engine start if all of the buses which power them are used for supplying power to the engine starter. This maximizes the current available for the starter, and may extend the life of the CCFL backlight in the display unit. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, May 14, 2007 9:56 PM Subject: Re: AeroElectric-List: Avionics Master At 07:28 PM 5/14/2007 -0700, you wrote: > >All, > >I'm working on my panel and I'm trying to decide if I should put an >Avionics Master switch. In my experience with rental planes this was nice >to have since there was one switch to turn everything on or off during >engine start or shutdown. > >Is there any reason not to add this feature? I'm planning an E-Bus and >Main Bus configuration similar to the Z-13/8 design. Why "similar to"? What feature do you find missing or performance goal that has gone lacking. Goto http://aeroelectric.com . . . and put 'avionics master' in the search box. After reviewing the discussions, help us out by citing where you perceive a return on investment for having the feature. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.