Crcuit Breaker question

[Mike Raviv]

As simple as that: are 28 V DC breakers usable in 12 V circuits?

I have access to some hi-quality 25 - 50 A pieces (for free), are they any good for me?

TNX and
BSTRGRDS

Mike
4X-ORV
going electric now.

[Transporter]

Mike,
28V breakers will work in a 14V system...however, the amperage ratings you've described are too high for most RV electrical circuits.

You might be able to use one of these breakers to protect your alternator circuit, depending on the rating of the alternator you plan to use (the breaker rating must equal or exceed the alternator rating).

For your other circuits you'll want fuses or circuit breakers to meet the maximum current needed by the device (with appropriate wire thickness); most devices we use on our planes use very low current, with the exception of the landing light/taxi light. As an example, Van's provides much smaller sizes in their wiring kit:

2 ES PBB-5 (5 amp)
1 PBB-5A CB (5 amp)
4 ES PBB-10 (10 amp)
1 ES PBB-10A CB (10 amp)
1 CB 1648-009-060 (60 amp-for alternator)

More information is available in Bob Nuckolls' book "The Aeroelectric Connection" (available from his website www.aeroelectric.com or other vendors). He also makes a good arguement for the use of automotive-style fuses instead of circuit breakers. Lots of other free wiring information on his website.

Good luck
Mike

[Mike Raviv]

TNX Mike

Indeed, I intend to use those breakers only in the places where high current is involved. Still can save a few bucks here and there.

BTW, the book you mentioned is already on order.

TNX again
BSTRGD

Mike
4X-ORV
Installing systems.