Do I Need Breakers for Each Battery

[Henderson]

Does it matter which side of the battery you fuse? + or -

positive is recommended.

 

[timselectric]

Does it matter which side of the battery you fuse? + or -

Always the + unless for some reason it is grounded. Can't think of any reason it would be. But had to cover all bases. (Possibly an old European mobile installation)

 

[Shimmy]

Does it matter which side of the battery you fuse? + or -

Convention is to fuse the + on a battery under 60V; high voltage batteries require + and -.

 

[Shimmy]

Always the + unless for some reason it is grounded. Can't think of any reason it would be. But had to cover all bases. (Possibly an old European mobile installation)

Only exception I am aware of is -48VDC telecom systems.

 

[timselectric]

Only exception I am aware of is -48VDC telecom systems.

They ground battery + ?

 

[sunshine_eggo]

Not sure if I'm right, but I always thought the reason the (+) is fuse/breakered is to maintain the grounds as the (-) are grounded.

 

[timselectric]

Not sure if I'm right, but I always thought the reason the (+) is fuse/breakered is to maintain the grounds as the (-) are grounded.

Overcurrent protection is always done on the ungrounded conductors.
DC systems (if grounded) are usually negative grounded. But in rare occasions it is the positive that is grounded. In those cases the Overcurrent protection would be put on the negative.

 

[HRTKD]

Always the + unless for some reason it is grounded. Can't think of any reason it would be. But had to cover all bases. (Possibly an old European mobile installation)

'67 MGB GT. Positive ground system. Not that it's relative to this discussion, but oddball systems like that do exist. I had to be careful when getting a jump start from another vehicle.

 

[timselectric]

'67 MGB GT. Positive ground system. Not that it's relative to this discussion, but oddball systems like that do exist. I had to be careful when getting a jump start from another vehicle.

Yup
That's why I covered my butt. lol

 

[HRTKD]

Yup
That's why I covered my butt. lol

Agreed. I was providing an example to back you up.

If the norm is to fuse on positive and I run into a system that is fused on negative, I'm going to be real careful and approach that system with kid gloves.

 

[Shimmy]

They ground battery + ?

Yeah, something about limiting corrosion on long copper phone lines. Not sure why it is still done for telecom and radio equipment though.

 

[JBennettBus]

Yeah, something about limiting corrosion on long copper phone lines. Not sure why it is still done for telecom and radio equipment though.

That was interesting enough to make me look it up. According to the internet, it started as a way to limit corrosion, just as you said, because back in the Dark Ages a lot of wire insulation was cloth based, and corrosion was more of a problem for telephone lines. Apparently it's still being done because modern insulation greatly reduces the corrosion problem but doesn't eliminate it.

So I learned something new tonight. Thanks!

 

[timselectric]

Me too.

 

[Brettw]

Always the + unless for some reason it is grounded. Can't think of any reason it would be. But had to cover all bases. (Possibly an old European mobile installation)

Here is what I'm referring too.