Cube battery fuses

[mrangry]

Initially I had planned to upgrade my house battery bank from 2 x 85ah agm batteries to 4 x 110ah agm batteries. As usual with anything to do with boats this grows arms and legs as you find so many other things that require attention/replacing.

I have now installed the four new batteries with new cables and rewired the isolator switches. I then realised that I had not fused the battery cables and bought some cube battery terminal fuses to fit the battery terminal studs. Am I right in thinking that I will also need to buy special isolated nuts to prevent the cable lug coming into contact with the terminal stud?

 

[pvb]

Yes.

 

[BabaYaga]

Alternatively, use this type of fuse block with isolated stud:
MRBF Terminal Fuse Block - 30 to 300A - Blue Sea Systems

 

[mrangry]

Alternatively, use this type of fuse block with isolated stud:
MRBF Terminal Fuse Block - 30 to 300A - Blue Sea Systems

I actually bought one of those and was shocked the fuse was not included at £28. It would be an expensive day out buying 4, one for each battery. For that reason i bought 4 cube fuses but will need to check stud size and order some.

 

[BabaYaga]

buying 4, one for each battery.

Very prudent. Be sure to use an isolated spanner when doing it all up.

 

[PaulRainbow]

It's almost always a total waste of time and money fitting individual fuses to all batteries in a bank. The fuses are only there to protect the cables, so unless they are in dander of shorting they don't need fusing. The main cable that goes to the isolator switches is normally all that might need to have a fuse.

 

[mrangry]

That is a good point Paul and looking at my set up I suppose if careful the risk of shorting cables is slim, so may just bite the bullet and fuse at the +ve junction post to the isolator.

 

[PaulRainbow]

That is a good point Paul and looking at my set up I suppose if careful the risk of shorting cables is slim, so may just bite the bullet and fuse at the +ve junction post to the isolator.

I'd fit a Megafuse just there. Keep the positive and negative cables clipped back, either side of the box and nothing can short. If you see anything that poses a risk, tie it back and/or fit covers on the positive terminal covers.