No need to get into a contest here. Of course the load determines the
breaker size, but the breaker size determines the wire size. This is
standard aircraft stuff. The reason is this: You may be using one breaker
for several loads but each wire coming from the breaker absolutely must be
able to withstand the full breaker current rating, should a short-to-ground
condition arise, and that full load current must not cause the wire to heat
and burn through its insulation. "Burn" is what we really do not want to
happen.



FAA AC 43-13 (current version) is the reference and will chart out how to
take into account factors such as continuous or intermittent load, wire
bundles, etc.



Also, the ground wire in each case must be at lease equal in size to the
supply wire.

Rick Hole



_____

From: Q-LIST@yahoogroups.com [mailto:Q-LIST@yahoogroups.com] On Behalf Of
boblj@comcast.net
Sent: Thursday, April 05, 2012 3:14 PM
To: Q-LIST@yahoogroups.com
Cc: Q-LIST@yahoogroups.com
Subject: Re: [Q-LIST] Wire suppliers







I would disagree with the post. The load should dictate the breaker size and
the wire size, you also need to take into account wether or not it is going
to be in a tight bundle of wires.

Bob Johnson

Dragonfly N211DF

DESERT BOB
----- Original Message -----
From: "Rick Hole" <r.hole@ieee.org <mailto:r.hole%40ieee.org> >
To: Q-LIST@yahoogroups.com <mailto:Q-LIST%40yahoogroups.com>
Sent: Wednesday, April 4, 2012 9:02:57 PM
Subject: [Q-LIST] Wire suppliers



The choice of wire size depends on usage. The more current, the larger the
wire size. Current load is determined solely by the breaker which protects
the wire, not by the needs of the load it is connected to. Some panel wires
can be 24g, some 22g, some 20g or larger.

Skygeek has done well for me, new fresh wire at excellent price and they
carry a wide range of sizes and colors:

http://search.skygeek.com/?vwcatalog=stylespilotshop
< http://search.skygeek.com/?vwcatalog=stylespilotshop
<http://search.skygeek.com/?vwcatalog=stylespilotshop&keywords=m22759>
&keywords=m22759 >
&keywords=m22759

Skycraft is a surplus dealer with really low prices. Their stock is older
but I have not had anything from them to reject:

http://www.skycraftsurplus.com/milspechookupwire.aspx

Rick Hole
Q builder between projects