Airplane wiring for dummies

RickWoodall · #1 01-23-2008, 08:12 AM

I have read a bunch of threads in the archives, and I have bought and really tried to work through Aeroelectric connection. Geeez, that is BORING, and i simply dont have the ability to read through more than a page or two at a time...i dont enjoy it.(why do these electrons want to go that way? how am i supposed to figure out the wire sizes? What needs a ground to the plane and what needs to come back to a central ground? Radio wires need to be how far from strobes wire, what if they are shielded UGGGH) I am a ways from doing panel/wiring but I am trying to start my planning and wire runs to wings, tail etc for the real basic stuff. A friend here suggested some EAA web info that i will look into. BUT does anyone have any really good suggestions to get the basics down and start my planning. Are the DVD's out there worth it, are there links to some other sites that folks found really helpful? I know tefzel wire, ohms law... blah blah... I just dont know where to start or how to get the master plan started. Help appreciated. Ideally a dvd "airplane wiring for dummies" that would allow me to "get" the basics/needs down so over the 6 months I can fine tune and adjust the plan and then get more indepth would be great. THANKS

bsacks05 · #2 01-23-2008, 09:56 AM

Rick,
I can certainly identify with your quandry. I am the same way with 'lectronics and really only grasp the simple stuff.
I started by determining what I wanted as far as lighting and panel goodies and made a list. My budget and personal feelings led me to go with basic day night VFR which kept my schematic simple. I did not draw up a personalized schematic but ended up using the VFR diagram from my Vans preview plans and incorporated some of the features from Aeroelectric Connection. There are sample drawings in that which are really helpful.
Then it was a matter of planning the panel layout, buying the switches and gizmos and mounting them in the panel. After that, it is wiring one thing at a time with lots of careful thought and planning as to how the wires are run and bundled.
It is a great learning process, but remember, you are not reinventing the wheel and the simpler the plan, the easier the execution.

Fearless · #3 01-23-2008, 10:04 AM

Thats the one that throws me. I see them on the Aeroelectric Connection diagrams but don't fully understand how to do them myself. I think I understand common grounds and local grounds but what the heck are shielded grounds - I think I'm suppose to have them on my magnetos.

grover · #4 01-23-2008, 10:20 AM

shielded wire keeps noisy things out of (or in) the shielded conductor. sometimes grounded at one end, sometimes grounded at both ends. depends on the use.

az_gila · #5 01-23-2008, 11:17 AM

Quote:

Originally Posted by Fearless

Thats the one that throws me. I see them on the Aeroelectric Connection diagrams but don't fully understand how to do them myself. I think I understand common grounds and local grounds but what the heck are shielded grounds - I think I'm suppose to have them on my magnetos.

If you follow AeroElectric Bob's schematics....

Then this page describes how the shielded grounds are shown...

http://books.google.com/books?id=0o1...djlCc#PPA40,M1

It's this little symbol...

Hope this helps... gil A

elippse · #6 01-23-2008, 12:02 PM

I have a plastic airplane, so I don't have the aluminium fuselage acting as a shield between my wiring and my radio antenna. Here's how I set up my wiring: I have three terminal boards mounted parallel and one above the other. The top one is my master and avionics buss used to connect to the circuit breakers from the battery/alternator, and the middle one is the buss used to connect to the loads. The bottom one is my return (ground) distribution. Here's how it works: I run a twisted pair of wires from the upper buss and the load bus to the circuit breakers. This way all of the current going to a load goes out on one wire to the CB and comes back on the other wire of the TP to the load buss, giving total cancellation of any EMI transmitted or received. Now from the load buss and the return buss I run a shielded-twisted-pair to each load, with both the return side of the TP and the shield connected to the return buss. Here again, all current flowing to the load returns in the adjacent wire, which, along with the shield, provides good EMI and RFI rejection. No "ground loops" here! Some avionics have different terminals for the chassis return and the circuit return, so here you would connect the shield to one and the return wire to the other, otherwise you would leave the shield un-connected. Also, from the master buss and the return buss I have a 10,000 uF electrolytic capacitor in parallel with a 1.0uF film capacitor in parallel with a 0.01 ceramic disc capacitor. The purpose of these is to establish an "AC" ground at the master buss. This serves as the source for transient currents so that they don't have to flow to/from the battery/alternator which have unbalanced conductors that will radiate these transients. One of the things youse guys with aluminium planes should keep in mind is that if you use the airframe as your return conductor, you can aid corrosian to take place in all overlapping joints in the conductive path if moisture is present in or around the joint.

p.s. I have a Van's T-shirt which has a message on the back which says " Friends don't let friends fly in plastic airplanes!" I also have a Lancair T-shirt that says "Friends don't let friends fly in airplanes that corrode!"

Sam Buchanan · #7 01-23-2008, 12:04 PM

Quote:

Originally Posted by RickWoodall

I have read a bunch of threads in the archives, and I have bought and really tried to work through Aeroelectric connection. Geeez, that is BORING, and i simply dont have the ability to read through more than a page or two at a time...i dont enjoy it.(why do these electrons want to go that way? how am i supposed to figure out the wire sizes? What needs a ground to the plane and what needs to come back to a central ground? Radio wires need to be how far from strobes wire, what if they are shielded UGGGH) I am a ways from doing panel/wiring but I am trying to start my planning and wire runs to wings, tail etc for the real basic stuff. A friend here suggested some EAA web info that i will look into. BUT does anyone have any really good suggestions to get the basics down and start my planning. Are the DVD's out there worth it, are there links to some other sites that folks found really helpful? I know tefzel wire, ohms law... blah blah... I just dont know where to start or how to get the master plan started. Help appreciated. Ideally a dvd "airplane wiring for dummies" that would allow me to "get" the basics/needs down so over the 6 months I can fine tune and adjust the plan and then get more indepth would be great. THANKS

This is an area that unfortunately has no shortcuts, unless you just want to write a big check to somebody who can wire your plane for you. It really boils down to knuckling down and getting up to speed on aircraft wiring architecture......in others words, doing our homework.

There is basic info in the RV build manual, and if that scheme fits you needs, then use it. There are charts in the manual that tell you how to size wire. If the AeroElectric diagrams fit your needs better, then use one of them for your cookbook and get with it.

The key to wiring is.....one wire at a time. I like to start at the battery and work back into the wiring scheme. Get the fat wires and contactors in place then start adding one circuit at a time. Use a highlighter to trace each run on the schematic as you add it.

If your needs require a custom design, and more than likely all our planes are now custom with the wide avionics choices we have, then it will be necessary for the builder to bore down into the circuit needs for each piece of equipment and decide how it fits in the overall plan.

None of us can give real specific guidance since all our planes are different. Bob's book is excellent, I didn't really grasp some of the stuff he was proposing until the second and third reading of it. Sorry I can't offer a "silver bullet".

jferraro17 · #8 01-23-2008, 12:23 PM

STEIN!!!!

Are you reading this?? Where is that DVD?!?!?!

Joe

flion · #9 01-23-2008, 12:46 PM

If you look on Blue Mountain Avionics website in the support download area, they have a document that simplifies things a lot. It's not quite complete; it looks like they were planning to market a complete wiring solution. But it's very helpful and much clearer than Bob's material. I kinda view the Aeroelectric Connection as a reference rather than a strict 'how-to'.

RickWoodall · #10 01-23-2008, 12:48 PM

(Bob's book is excellent, I didn't really grasp some of the stuff he was proposing until the second and third reading of it. Sorry I can't offer a "silver bullet")

ARE YOU KIDDING.... your telling me to read it 3 times. Good lord! I cant finish it once. You must have a different version than mine HaHa, i am trying to sort my way through it...made lots of progress...but it still seems someone could make a few bucks doing a quick course so us "not engineer" types can understand the attack plan and the basic strategy/layout. I'll just keep reading. Not enjoying it though. I want to learn and do it myself, not looking to sub it out...just find this learning curve is the most difficult for me out of all the new skills one must learn.