---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 10/07/18: 11 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:13 AM - Re: Question: can these wires be put in one wire bundle? (zwakie) 2. 06:45 AM - Re: Re: Question: can these wires be put in one wire bundle? (FLYaDIVE) 3. 10:42 AM - Re: Question: can these wires be put in one wire bundle? (Robert L. Nuckolls, III) 4. 10:52 AM - Re: Re: Question: can these wires be put in one wire bundle? (Robert L. Nuckolls, III) 5. 11:43 AM - Re: Re: Question: can these wires be put in one wire bundle? (FLYaDIVE) 6. 01:43 PM - Re: Re: Question: can these wires be put in one wire bundle? (Robert L. Nuckolls, III) 7. 02:22 PM - Re: Question: can these wires be put in one wire bundle? (zwakie) 8. 03:47 PM - Rear battery earthing structure (Neil Parkinson) 9. 04:23 PM - Re: Rear battery earthing structure (Robert L. Nuckolls, III) 10. 06:43 PM - Re: Re: Question: can these wires be put in one wire bundle? (Rick Beebe) 11. 09:02 PM - Re: Re: Question: can these wires be put in one wire bundle? (jim) ________________________________ Message 1 _____________________________________ Time: 01:13:19 AM PST US Subject: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? From: "zwakie" BARRY CHECK 6 wrote: > Keep the Transponder COAX out of the bundle. Run it as far away from ALL other wires as possible and away from other COAX also. Thanks Barry. I guess I should have mentioned that in my opening post: the radio and transponder antennas are aft of the units, so both coax cables will not be in the bundle. -------- Marcel Zwakenberg XS TG || 912ULS || PH-SBR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483671#483671 ________________________________ Message 2 _____________________________________ Time: 06:45:25 AM PST US From: FLYaDIVE Subject: Re: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? Oh, Marcel: Some other tricks I do: 1 - I use Black and Red wire for primary B+ voltages. 2 - I twist the B+ wires - about 4 to 6 twists per inch. This helps in keeping noise out of the system. 3 - Use shielded cables for Audio lines. 4 - Audio lines are Grounded ONLY at the source - Example: At the radio and at the intercom. 5 - If you have two set of similar wires - Example: A RS232 from one Nav/Comm and another Nav/Comm keep them apart and/or use shielded wires. Side note: I have installed 4 sets of Garmin G5's. NOISE is a huge issue with them. I use Toroids on the B+ hot wires, wrap them well, the more wraps the better and ONLY on the B+ Positive wire. Good NOISELESS Luck, Barry ________________________________ Message 3 _____________________________________ Time: 10:42:56 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Question: can these wires be put in one wire bundle? >My plan was to put all the wires for both units into a single wire >bundle except for the mic, phone and ptt wires. In addition I plan >of putting a single power and ground wire into this bundle, >connecting to a separate fuseblock near the units in the back (of >course, the AWG of these will be scaled upwards appropriately). There are no noise problems associated with bundling mixed signals. It's done in the big birds all the time . . . even the shielded wires. The whole reason for shielding is to break the electro-static coupling path between potential antagonist/ victim pairs. Suggest you not put part of your bus structure in the rear. Keep it simple, one fuse for each protected feeder from the central bus structure to each powered device. A combined ground for all rear mounted devices works. We show this 'star' configuration grounding system in Figure Z-15 with an extension to the instrument panel . . . a second extension to rear mounted appliances works too. >I will also need to put two shielded audio cables back to front to >connect into the AP60 audio mixer that is also in the back near the >radio/xpdr units. I guess it's best to keep those separate from this >bundle, but as these audio wries will be running sort of parallel to >mentioned wire bundle what is the minimum distance between these two >runs to avoid audio issues? Also: if my guess of keeping the audio >wires separate is wrong, please let me know. I would bundle all power and ground wires from panel rearward together including the audio. Further, there is no reason to route coax separately . . . the signal isolation physics for shielding applies to radio frequencies as it does for low level audio. Spent 40 years herding electrons in everything from C150 to B400 and Learjets. There is vigorous competition between the various system groups for space, weight and volume on the airplane. Finding placed to put things and wire it all up can be challenging. Worries about mixed signals in wire bundles is wwaaaayyy down on the list of concerns. Proper design and qualification of the appliances makes 'em installer/user friendly. It's called electromagnetic compatibility or EMC for short. Bob . . . ________________________________ Message 4 _____________________________________ Time: 10:52:57 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? At 08:44 AM 10/7/2018, you wrote: >Oh, Marcel: > >Some other tricks I do: >1 - I use Black and Red wire for primary B+ voltages. >2 - I twist the B+ wires - about 4 to 6 twists >per inch.=C2 This helps in keeping noise out of the system. Noise from where to where? >3 - Use shielded cables for Audio lines. >4 - Audio lines are Grounded ONLY at the source >- Example: At the radio and at the intercom. Treat shields per manufacturer's installation instructions. Shields are sometimes part of the energy management. >5 - If you have two set of similar wires - >Example: A RS232 from one Nav/Comm and another >Nav/Comm keep them apart and/or use shielded wires. There is no reason for doing this. If we attempted to keep everythting separated behind the panel of a King Air, it would look like a spider-web as opposed to an organized, mechanically secure installtion. >Side note:=C2 I have installed 4 sets of Garmin >G5's.=C2 NOISE is a huge issue with them.=C2 I use >Toroids on the B+ hot wires, wrap them well, the >more wraps the better and ONLY on the B+ Positive wire. Noise from where to where? What is the nature of the noise? Are these not a DO160 qualified system? Is the G5 the victim or the antagonist? Bob . . . ________________________________ Message 5 _____________________________________ Time: 11:43:49 AM PST US From: FLYaDIVE Subject: Re: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? Bob: On Sun, Oct 7, 2018 at 1:56 PM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 08:44 AM 10/7/2018, you wrote: > > Oh, Marcel: > > Some other tricks I do: > 1 - I use Black and Red wire for primary B+ voltages. > 2 - I twist the B+ wires - about 4 to 6 twists per inch.=C3=82 This help s in > keeping noise out of the system. > > > Noise from where to where? > Barry - When I know where the noise is coming from I attack the noise. In the meantime I do what I can to prevent the noise from attacking the system. > 3 - Use shielded cables for Audio lines. > 4 - Audio lines are Grounded ONLY at the source - Example: At the radio > and at the intercom. > > > Treat shields per manufacturer's installation instructions. > Shields are sometimes part of the energy management. > > 5 - If you have two set of similar wires - Example: A RS232 from one > Nav/Comm and another Nav/Comm keep them apart and/or use shielded wires. > > > There is no reason for doing this. > Barry - There sure is! You do what you can where you can to keep the noise down OR you are forced to live with it. > If we attempted > to keep everythting separated behind the panel > of a King Air, it would look like a spider-web > as opposed to an organized, mechanically > secure installtion. > Barry - Spider Web. They are very organized. It's the Rat's Nest I despise. You keep separated what you can. You use shielded wire where you can. You of course do not have to go weird in your actions. But, the issue becomes a problem AFTER the wiring is complete and THEN you find you have noise. Then you scramble with capacitors, coils and filter networks - Maybe or Maybe not being able to solve the problem ONLY to find proper wiring would have eliminated the noise. Why scramble for a band-aid instead of eliminating the problem? > Side note:=C3=82 I have installed 4 sets of Garmin G5's.=C3=82 NOISE is a huge > issue with them.=C3=82 I use Toroids on the B+ hot wires, wrap them well , the > more wraps the better and ONLY on the B+ Positive wire. > > > Noise from where to where? What is the nature > of the noise? Are these not a DO160 > qualified system? > Barry - I do not know! They are a Garmin system (LCD Attitude Indicator, ASI, VSI, HSI and they interface to Panel Mounted GPS & A/P) pretty much an all glass panel. https://www.garmin.com/en-US/blog/aviation/announcement-g5-electronic-fligh t-instrument-as-dghsi-in-certificated-aircraft/ > Is the G5 the victim or > the antagonist? > Barry - It is the VICTIM, as the G5 has a Noise Testing program built into them. The big issue of noise, is because it has a remote mounted Magnetometer. Barry > ________________________________ Message 6 _____________________________________ Time: 01:43:09 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? >>Some other tricks I do: >>1 - I use Black and Red wire for primary B+ voltages. >>2 - I twist the B+ wires - about 4 to 6 twists >>per inch.=C3=82=C2 This helps in keeping noise out of the system. > >=C2 Noise from where to where? > >Barry - When I know where the noise is coming >from I attack the noise.=C2 In the meantime I do >what I can to prevent the noise from attacking >the system. >Barry - There sure is!=C2 You do what you can >where you can to keep the noise down OR you are forced to live with it. You speak of 'the noise' . . . never met a noise problem I couldn't whip . . . albeit some were pretty bizarre. But in decades of helping push certified iron down the production line, not once have I encountered a noise issue that was cured or would have be prevented by: Adding inductors to power lines of a properly qualified appliance, twisting any pairs of wires together, adding shielding above or beyond that specified by the manufacturer of the system or adding/increasing separation of coaxes from other wires in the airframe. >Barry - Spider Web. They are very organized. It's the Rat's Nest I despise. >You keep separated what you can. You use shielded wire where you can. >You of course do not have to go weird in your actions. >But, the issue becomes a problem AFTER the wiring is complete and THEN you >find you have noise. Then you scramble with capacitors, coils and filter >networks - Maybe or Maybe not being able to=C2 solve the problem ONLY to >find proper wiring would have eliminated the noise. I have never encountered a case of 'improper wiring'. If moving a wire or adding an heretofore unspecified shield, then there's something seriously wrong with the selection of hardware. I prefer to identify the victim, point of entry for noise into that system. Identify the noise source. Identify the propagation pathway. Then craft a 'fire-break' in that pathway to reduce interference to acceptable levels. >Why scramble for a band-aid instead of eliminating the problem? But Barry, >>Side note: I have installed 4 sets of Garmin G5's. >>NOISE is a huge issue with them. I use Toroids on the B+ hot >>wires, wrap them well, the more wraps the better and ONLY on the >>B+ Positive wire. > > Noise from where to where? What is the nature > of the noise? Are these not a DO160 > qualified system? > >Barry - I do not know! They are a Garmin system (LCD Attitude Indicator, ASI, >VSI, HSI and they interface to Panel Mounted GPS >& A/P) pretty much an all glass panel. > >https://www.garmin.com/en-U S/blog/aviation/announcement-g5-electronic-flight-instrument-as-dghsi-in-cer tificated-aircraft/ Okay, if these are going into TC ships, then they must have been vetted for EMC. If they succumb to some stimulus in an existing airframe, the stimulus has to be much larger and/or of a nature not anticipated by the folks who craft certification protocols. If a filter was found necessary to protect functionality of the Garmin system, how do you know that the same antagonist isn't deleterious to other systems? What was the core material used and number of turns. What was the value of inductance added with this filter (speaks to the spectrum of noise for which his would be an effective filter). Are you sure that the core 'packed with as many turns as possible' was not saturated with the DC current flow through its winding? > >Is the G5 the victim or >the antagonist? > >Barry - It is the VICTIM, as the G5 has a Noise >Testing program built into them. >The big issue of noise, is because it has a remote mounted Magnetometer. What does the G5 installation manual say about noise? Remote magnetometers have been around for nearly a century and yes, need to be thoughtfully installed to avoid interference to its accuracy . . . but adding inductance to the power supply line for an input qualified to Mil-STD-704 stimulus would not be one of the factory recommended fixes. Bob . . . ________________________________ Message 7 _____________________________________ Time: 02:22:33 PM PST US Subject: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? From: "zwakie" nuckolls.bob(at)aeroelect wrote: > > There are no noise problems associated > with bundling mixed signals. It's done > in the big birds all the time . . . even > the shielded wires. The whole reason for > shielding is to break the electro-static > coupling path between potential antagonist/ > victim pairs. > That is how I understood it from the 'Conneciton, thanks for confirming. nuckolls.bob(at)aeroelect wrote: > > Suggest you not put part of your bus structure > in the rear. Keep it simple, one fuse for each > protected feeder from the central bus structure > to each powered device. A combined ground for > all rear mounted devices works. We show this > 'star' configuration grounding system in Figure > Z-15 with an extension to the instrument panel . . . > a second extension to rear mounted appliances > works too. > I know star conifgurations are not ideal, but this is going to be an intermediate solution until I have my new panel ready for installation. I thought for a limiited time I should get away with it. Am I assuming wrong? nuckolls.bob(at)aeroelect wrote: > > I would bundle all power and ground wires from panel > rearward together including the audio. > Will do, thanks. nuckolls.bob(at)aeroelect wrote: > > Further, there > is no reason to route coax separately . . . the > signal isolation physics for shielding applies > to radio frequencies as it does for low level > audio. > Point taken. In my case all coax runs more aft, so no issue there... Thanks Bob for taking the time to answer my questions in detail, really appreciated! Marcel -------- Marcel Zwakenberg XS TG || 912ULS || PH-SBR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483690#483690 ________________________________ Message 8 _____________________________________ Time: 03:47:47 PM PST US From: Neil Parkinson Subject: AeroElectric-List: Rear battery earthing structure Hi Everybody. Im building an RV8 with a rear battery location. Can I please have some advice on the earthing structure . Can I just earth the battery to the structure in the rear , then take it the common earth at the panel ? Or is it worth running some asw2 cable to earth the panel , or the engine ?? I will have some rear avionics equipment , should I run the earth from the panel to these ? Or just tap of the structure locally ? Im not sure when I start running into earth loop issues ?? Many thanks. Neil. ________________________________ Message 9 _____________________________________ Time: 04:23:11 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Rear battery earthing structure At 05:46 PM 10/7/2018, you wrote: >Parkinson > >Hi Everybody. > >I=99m building an RV8 with a rear battery location. > >Can I please have some advice on the earthing >structure . Can I just earth the battery to the >structure in the rear , then take it the common >earth at the panel ? Or is it worth running some >asw2 cable to earth the panel , or the engine ?? Ground battery locally http://aeroelectric.com/Pictures/Batteries/Battery_Install_OBrien_3.jpg http://aeroelectric.com/Pictures/Grounding/Local_Battery_Grounds_1.jpg Install ground bus on firewall. http://aeroelectric.com/Pictures/Grounding/Forest_of_Tabs_Ground_Kit.pdf http://aeroelectric.com/Pictures/Grounding/gnd_bus.jpg Run braided-flat-wire from crankcase to firewall ground stud. http://aeroelectric.com/Pictures/Grounding/Braided%20Copper%20Bond%20Straps. jpg >I will have some rear avionics equipment , >should I run the earth from the panel to these ? >Or just tap of the structure locally ? What kind of avionics? Anything with audio or digital signal leads? Bob . . . ________________________________ Message 10 ____________________________________ Time: 06:43:02 PM PST US Subject: Re: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? From: Rick Beebe On 10/7/2018 2:41 PM, FLYaDIVE wrote: > Is the G5 the victim or > > the antagonist? > > Barry - It is the VICTIM, as the G5 has a Noise Testing program built > into them. > The big issue of noise, is because it has a remote mounted Magnetometer. The GMU11 magnetometer is susceptible to noise, as I discovered. I ended up rewiring my strobe lights before it would pass the interference test. To be fair, I mounted the GMU11 in the tail (fiberglass plane) in the spot where the Whelen powerpack used to live. I had replaced the Whelen units with Aveo LED units but used the existing wire so it was spliced right near the GMU 11. Also the shields were not contiguous out to the lights. In the end I pulled new shielded wire from the lights directly to the panel switch and that solved my interference problem. Perhaps if I had located the magnetometer in the wing I wouldn't have had an issue. But I don't think it's fair to say the G5 is susceptible to noise. By their nature, magnetometers are sensitive beasts. --Rick ________________________________ Message 11 ____________________________________ Time: 09:02:08 PM PST US From: "jim" Subject: RE: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? Noise problems are sometimes present no matter how careful the builder has been. That is why I read this forum, just to get ideas how to chase them. When a friend ask me for ideas on how to find an intermittent source of noise in his GlassStar, I gave him some ideas based on what I had learned here. He had no luck and was just ready to give up when he accidently noticed his HOBBS meter was running intermittently. He had a standard arrangement where a switch in the oil pressure line turned on the HOBBS meter so it recorded actual engine run time. When he replaced the oil pressure switch that activated the HOBBS meter, the intermittent noise went away. That was a total accidental situation. I doubt anyone would have suspected a bad set of points in an oil pressure switch of causing the problem. You learn something new every day if you just pay attention to what you can learn by other's experiences. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com On Behalf Of zwakie Sent: Sunday, October 7, 2018 4:22 PM Subject: AeroElectric-List: Re: Question: can these wires be put in one wire bundle? nuckolls.bob(at)aeroelect wrote: > > There are no noise problems associated > with bundling mixed signals. It's done > in the big birds all the time . . . even > the shielded wires. The whole reason for > shielding is to break the electro-static > coupling path between potential antagonist/ > victim pairs. > That is how I understood it from the 'Conneciton, thanks for confirming. nuckolls.bob(at)aeroelect wrote: > > Suggest you not put part of your bus structure > in the rear. Keep it simple, one fuse for each > protected feeder from the central bus structure > to each powered device. A combined ground for > all rear mounted devices works. We show this > 'star' configuration grounding system in Figure > Z-15 with an extension to the instrument panel . . . > a second extension to rear mounted appliances > works too. > I know star conifgurations are not ideal, but this is going to be an intermediate solution until I have my new panel ready for installation. I thought for a limiited time I should get away with it. Am I assuming wrong? nuckolls.bob(at)aeroelect wrote: > > I would bundle all power and ground wires from panel > rearward together including the audio. > Will do, thanks. nuckolls.bob(at)aeroelect wrote: > > Further, there > is no reason to route coax separately . . . the > signal isolation physics for shielding applies > to radio frequencies as it does for low level > audio. > Point taken. In my case all coax runs more aft, so no issue there... Thanks Bob for taking the time to answer my questions in detail, really appreciated! Marcel -------- Marcel Zwakenberg XS TG || 912ULS || PH-SBR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483690#483690 ------------------------------------------------------------------------------------- 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.