ABYC 7 circuit protection rule-gctid402270

[Guest]

How do I determine what size fuse I should use to protect my house batteries and my start battery? House batteries are 4 6v (no amph rating on them!), and the start is a regular 12v 850 cc A battery.

[JimMc]

You rate the House Battery fuse based on the cable size/capacity to the house bank. If the House Bank and the cabling is in the engine bay you reduce the fuse rating by about 10% below the cable capacity.

I assume you are planning to install one of the battery terminal style house bank fuses. I installed one a couple of years ago.

The ABYC specifies fuses are not required or recommended for starting batteries.

[Guest]

God, what a bone head I am! Of course if I thought about it a bit more then I wouldn't have posted the questions. No different than breaker sizing in residential wiring.

So yes, I am planning on installing Blue Sea Terminal Fuses on the house bank to protect that circuit, it's fed with a 1/0 cable (where do I find the current carrying capacity of marine cables so I can size the fuse?). I also thought on putting one on the starter battery but not in series with the main motor's starter. I have a Yamaha T9.9, Panther T4 steering system on the starter battery so that was the circuit I was planning on protecting. I suppose the T4 should have it's own fuse since the gage of the wiring is much smaller. I thought of putting everything on the house battery but thought it was a better idea to have the kicker charge up the start battery while in use.

Gary

[johnrupp]

garball wrote:
God, what a bone head I am! Of course if I thought about it a bit more then I wouldn't have posted the questions. No different than breaker sizing in residential wiring.

So yes, I am planning on installing Blue Sea Terminal Fuses on the house bank to protect that circuit, it's fed with a 1/0 cable (where do I find the current carrying capacity of marine cables so I can size the fuse?). I also thought on putting one on the starter battery but not in series with the main motor's starter. I have a Yamaha T9.9, Panther T4 steering system on the starter battery so that was the circuit I was planning on protecting. I suppose the T4 should have it's own fuse since the gage of the wiring is much smaller. I thought of putting everything on the house battery but thought it was a better idea to have the kicker charge up the start battery while in use.

Gary

Gary,

The chart in the link should answer your questions.

[[/url]http://www.marinco.com/page/wire-tech-data

[johnrupp]

garball wrote:
God, what a bone head I am! Of course if I thought about it a bit more then I wouldn't have posted the questions. No different than breaker sizing in residential wiring.

So yes, I am planning on installing Blue Sea Terminal Fuses on the house bank to protect that circuit, it's fed with a 1/0 cable (where do I find the current carrying capacity of marine cables so I can size the fuse?). I also thought on putting one on the starter battery but not in series with the main motor's starter. I have a Yamaha T9.9, Panther T4 steering system on the starter battery so that was the circuit I was planning on protecting. I suppose the T4 should have it's own fuse since the gage of the wiring is much smaller. I thought of putting everything on the house battery but thought it was a better idea to have the kicker charge up the start battery while in use.

Gary

Gary,

The chart in the link should answer your questions.

http://www.marinco.com/page/wire-tech-data

[JimMc]

Gary

I have 2/0 cable and I fused it at 250A. I have never blown that fuse even when I stalled the windlass with a monster hunk of the bottom recently.

For 1/0 the chart says 242A in the Engine Bay. Blue Sea has them for 200A, 225A and 250A as well as smaller and larger.

[Guest]

Thanks guys for pointing me in the right direction. Here's a resource sent to me by Blue Sea Systems. http://bluesea.com/viewresource/529

Cheers,

Gary.