Fuse for pair 6v Batteries in series

CharlesinGA wrote:

RoyB wrote:
This protects your wiring from a dead short. Those batteries can produce a hugh amount DC Current. Could start a fire it is so much...

My in-line fuse is 130AMPS for three 12VDC Batteries in parallel...

These batteries will demand a good 17-20 AMPD DC current per battery in the 12VDC battery bank when being charged and I in turn will load them down to 20-25AMPS DC current from from usual loads when camping off the ogris...

Having this protection is a must have for me...

I use one of the BLUE SEA FUSE assemblies...


Roy Ken

I'm thinking one of these in the ground cable for the house batteries would be a good thing.

Charles

It's the usual practice to fuse the positive lead rather than the ground lead. In the particular case of a main battery fuse it probably makes less difference than elsewhere; however, in general, fusing the positive near the source is the most effective as fusing the ground return doesn't always protect against shorts to the chassis (which are among the more common faults) as the chassis ground can often bypass the fuse.

RoyB wrote:
This protects your wiring from a dead short. Those batteries can produce a hugh amount DC Current. Could start a fire it is so much...

My in-line fuse is 130AMPS for three 12VDC Batteries in parallel...

These batteries will demand a good 17-20 AMPD DC current per battery in the 12VDC battery bank when being charged and I in turn will load them down to 20-25AMPS DC current from from usual loads when camping off the ogris...

Having this protection is a must have for me...

I use one of the BLUE SEA FUSE assemblies...


Roy Ken

I'm thinking one of these in the ground cable for the house batteries would be a good thing.

Charles

er78mph wrote:
Hello and thanks to all in advance!
I read that one should have a fuse at the batteries just in case? What's the purpose of this installation? I want to protect the batteries especially after paying so much for them:) I could not really find any info on how to do this? Can anyone shed some light?

The fuse is not to protect the batteries, The fuse is to protect the wiring.

10Ga wire 30 amps. and so on... The bigger the wire, the bigger the fuse.... An electrical shop can give you recommendations or you can dig up a wire chart.. Alas, I do not think I have one on this laptop.

I think you said you were relocating your batteries? If it's a long run to the main fuse, then you're right, you should fuse it near the batteries too. It's all about the propensity for wire damage upstream of the fuse, so if the wires between the battery and main fuse (I'm sure your camper has one) can't realistically get damaged, rub thru the insulation, etc, then it is theoretically not needed at all.
In Roys case above, 130A seems like too big a fuse to me. Fuses should only be sized nominally larger than the max possible/intended amp draw at peak. Although if he has the charging circuit (I assume) wired with sufficient size wire for a 100A load then it'll handle 130A long enough without heating the wire enough to burn it up to pop the fuse.
Check out this site. Www.bcae1.com. It explains about anything you'd need to know about DC wiring. Particularly for car stereos, but the Principle is the same for your camper batteries.

Your RV should have a battery fuse as part of the original installation.
The fuse is to protect the wire. Did something happen to it?

a main battery cable being dead shorted..

you Could have a Fire.
you Could have a battery explosion.
and I have seen both types. in Cars/trucks.

Fyi,, you can use a single 12 volt battery and a metal coat hanger and do steel welding...
and that is how I welded new exhaust systems in cars in the 1960-1970's.

This protects your wiring from a dead short. Those batteries can produce a hugh amount DC Current. Could start a fire it is so much...

My in-line fuse is 130AMPS for three 12VDC Batteries in parallel...

These batteries will demand a good 17-20 AMPD DC current per battery in the 12VDC battery bank when being charged and I in turn will load them down to 20-25AMPS DC current from from usual loads when camping off the ogris...

Having this protection is a must have for me...

I use one of the BLUE SEA FUSE assemblies...


Roy Ken