Matronics Email Lists :: View topic - Farraday cage for power distribution?

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Farraday cage for power distribution?

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

Arthur.Treff(at)smartm.co
Guest

Posted: Thu Jun 22, 2006 9:29 am Post subject: Farraday cage for power distribution?

I've got a wire routing question for the list.

 

Three connections are on the battery side of the starter solenoid on the

firewall:

 

1) 2AWG from the battery solenoid in the rear of the aircraft.

2) 4AWG from the primary alternator output.

3) 2AWG going aft to power the fuse blocks located behind the instrument

panel.

 

The whole ship has been wired, fuse blocks, single point ground, battery

cable, etc.  I need to run the fuse block supply (#3 above) and the best

route to the fuse blocks behind the instrument panel will put the supply

cable right behind the avionics stack, running parallel to the rear of

the radio trays, specifically the Garmin 430.  Is this OK?  Would it be

OK if I constructed some sort of Farraday shield out of copper pipe and

a ground wire?  I did a google search and searched the Matronics

archives, but can't see if anyone's covered this.  Thanks for your help.

 

Art Treff

Asheville, NC

N666AT  RV-8

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

rv8ch

Joined: 10 Jan 2006
Posts: 250
Location: Switzerland

Posted: Thu Jun 22, 2006 10:33 am Post subject: Farraday cage for power distribution?

 	  Quote: 	
		   Three connections are on the battery side of the starter solenoid on the

 firewall:

  

 1) 2AWG from the battery solenoid in the rear of the aircraft.

 2) 4AWG from the primary alternator output.

 3) 2AWG going aft to power the fuse blocks located behind the instrument

 panel.


	


Wow - that's a lot of umpf for the fuse block.  I think I'm using maybe

AWG#10 for my fuse blocks.



 	  Quote: 	
		   The whole ship has been wired, fuse blocks, single point ground, battery

 cable, etc.  I need to run the fuse block supply (#3 above) and the best

 route to the fuse blocks behind the instrument panel will put the supply

 cable right behind the avionics stack, running parallel to the rear of

 the radio trays, specifically the Garmin 430.  Is this OK?  


	


I don't recall reading anything in Bob's book that indicates that

this would be a problem.  Hopefully some of the gurus will chime in.



-- 

Mickey Coggins

http://www.rv8.ch/

#82007 finishing

do not archive

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

_________________
Mickey Coggins
http://www.rv8.ch/

nuckollsr(at)cox.net
Guest

Posted: Thu Jun 22, 2006 5:33 pm Post subject: Farraday cage for power distribution?

At 10:25 AM 6/22/2006 -0700, you wrote:



 	  Quote: 	
		  

<Arthur.Treff(at)smartm.com>



I've got a wire routing question for the list.



Three connections are on the battery side of the starter solenoid on the

firewall:



1) 2AWG from the battery solenoid in the rear of the aircraft.


	


    plenty big . . .



 	  Quote: 	
		  2) 4AWG from the primary alternator output.


	


   plenty big too . . .



 	  Quote: 	
		  3) 2AWG going aft to power the fuse blocks located behind the instrument

panel.


	


   A bit too much. Consider that full load on the fuse block

   will not exceed rating of alternator and is generally limited

   by design to something on the order of 75 to 80 percent of

   rating. If you have a 40A alternator, #8 is good, a 60A alternator

   would prompt a #6 bus feeder.



 	  Quote: 	
		  

The whole ship has been wired, fuse blocks, single point ground, battery

cable, etc.  I need to run the fuse block supply (#3 above) and the best

route to the fuse blocks behind the instrument panel will put the supply

cable right behind the avionics stack, running parallel to the rear of

the radio trays, specifically the Garmin 430.  Is this OK?


	




   Beats me. Many a high current, fat wire has been run along side

   potential victims with no observable effects . . .but then

   there are fat wires that DO couple alternator noise into

   vulnerable wires when given the opportunity.



   The rule of thumb is not to have fat power wires and

   small signal wires share spaces. There's no guarantee

   that it's necessary but I prefer to eliminate the

   possibility of problems by observing the rules.



 	  Quote: 	
		     Would it be

OK if I constructed some sort of Farraday shield out of copper pipe and

a ground wire?  I did a google search and searched the Matronics

archives, but can't see if anyone's covered this.  Thanks for your help.


	


   Why not drop the feeder to 6 or 8 awg and re route it? Save

   weight and hassles to boot while eliminating the potential

   for problems by design.



   Bob . . .

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

sportav8r(at)aol.com
Guest

Posted: Thu Jun 22, 2006 6:00 pm Post subject: Farraday cage for power distribution?

Each of those avionics boxes you are worried about is inside its own Farraday cage (called a chassis), so I don't think it's an issue, really.

 

-Bill B 

 

--

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum