Determing Size Amp Fuses

[Mike1990]

How do i determine what fuse i would need for an application? because i want to connect the neons(using a 5 amp fuse) and the amp to a fused distro block and need to know how i would determine what amp fuse i would need to place in the distro block.

[ashley106]

i dint no this either but wen choosing i just chosen the same fuse as used in the wiring kit so if u have a 2000w wiring kit get the same size fuse that is in that wiring kit for the distro block

[loudandproud205]

go for same size as front there is an equasion but cant be arsed really

[Mike1990]

Is there a table i could find the fuse value for?

[mechsman]

How do i determine what fuse i would need for an application? because i want to connect the neons(using a 5 amp fuse) and the amp to a fused distro block and need to know how i would determine what amp fuse i would need to place in the distro block.

Basically just go with just under the max size fuse for the cable coming into the block or whatever the block is rated for. I.e. If the cable coming into the block is rated for 50 amps put a 40 amp fuse in the cable just before the block. The sum of all the fuses for the stuff hanging off the block should not exceed that rating unless u know that not all the stuff will be on together n pulling maximum amps.

This is the safe approach but reliable.

[Mike1990]

Basically just go with just under the max size fuse for the cable coming into the block or whatever the block is rated for. I.e. If the cable coming into the block is rated for 50 amps put a 40 amp fuse in the cable just before the block. The sum of all the fuses for the stuff hanging off the block should not exceed that rating unless u know that not all the stuff will be on together n pulling maximum amps.

This is the safe approach but reliable.Thanks mate, but would i be able to not use a fuse on the wires and put a fuse in the distro block for all the applications going into the block?

[mechsman]

Thanks mate, but would i be able to not use a fuse on the wires and put a fuse in the distro block for all the applications going into the block?

Always always always fuse the main supply cable as close to the battery as possible. The reason is to prevent disaster happening if the cable rubs through or gets cut/sliced/caught on sumthing and creates a short circuit. If you have a fuse at the battery end it will simply blow n that will be that. If, however, u have no fuse in the cable at the battery end the battery could dump approximately 400~500 or more amps (depending which batt u have) through the direct short circuit that had been created. This would result in the cable getting red hot n setting fire to stuff, assumming neither the cable or the batt exploded first!

Having said that you may get away with it if you used a very short run from the batt to the distrib box and you were very sure that nothing could rub/cut the cable. I would still fuse it as close to the batt as possible for peace of mind.

[Mike1990]

Always always always fuse the main supply cable as close to the battery as possible. The reason is to prevent disaster happening if the cable rubs through or gets cut/sliced/caught on sumthing and creates a short circuit. If you have a fuse at the battery end it will simply blow n that will be that. If, however, u have no fuse in the cable at the battery end the battery could dump approximately 400~500 or more amps (depending which batt u have) through the direct short circuit that had been created. This would result in the cable getting red hot n setting fire to stuff, assumming neither the cable or the batt exploded first!

Having said that you may get away with it if you used a very short run from the batt to the distrib box and you were very sure that nothing could rub/cut the cable. I would still fuse it as close to the batt as possible for peace of mind.Ok thanks, so if i used a 4 gauge wire from the battery to the distro block and used a fuse just lower then the max fuse size for the size of that wire, and then connect the neons and the amp to the distro block... everything would be ok?

[mechsman]

Ok thanks, so if i used a 4 gauge wire from the battery to the distro block and used a fuse just lower then the max fuse size for the size of that wire, and then connect the neons and the amp to the distro block... everything would be ok?

Yup, assuming its a fused distrib block. (i.e each output fused seperately). If its not a fused block I would say its worth putting a fuse on each output as (for example) you wouldn't want a set of blown neons 2 suddenly pull a massive current spike from the block (before the main fuse blew) and damage ure amp.

[Mike1990]

Yup, assuming its a fused distrib block. (i.e each output fused seperately). If its not a fused block I would say its worth putting a fuse on each output as (for example) you wouldn't want a set of blown neons 2 suddenly pull a massive current spike from the block (before the main fuse blew) and damage ure amp.I would need to connect a fuse on the power wire to the neons and amp aswell?

[mechsman]

If you want to be totally safe and protect the kit then yes. Should go something like this: \/

Batt
|
Fuse (big)
|
|
|
|
|
Block
| |
F F
| |
| |
| |
| |
A N

F= small fuse
A = amp
N = Neons

[loudandproud205]

think your going bout it wrong way really how you gonna turn neon on and of

[Mike1990]

If you want to be totally safe and protect the kit then yes. Should go something like this: \/

Batt
|
Fuse (big)
|
|
|
|
|
Block
| |
F F
| |
| |
| |
| |
A N

F= small fuse
A = amp
N = NeonsI'm understanding better now.. but if the distro block has a fuse holder, could i use that instead of putting a fuse holder in the power wire to the neons and amp?

[mechsman]

Ah righty. If the distrib block already has fuses in it then you don't need to have the seperate fuses after the block. You WILL still need the main fuse as close to the battery as possible to prevent meltdown should the cable between the batt and the distrib block become shorted.

loudnproud205: put a switch in the line after the distribution block!?!?

[Mike1990]

Ah righty. If the distrib block already has fuses in it then you don't need to have the seperate fuses after the block. You WILL still need the main fuse as close to the battery as possible to prevent meltdown should the cable between the batt and the distrib block become shorted.

loudnproud205: put a switch in the line after the distribution block!?!?Thank you, also last question... should i put a 80 amp fuse between the battery and the block? also, what fuse would i need to use for the amp? just below the max size fuse from the amp power wire?

[mechsman]

If you have cable that is rated for 80 amps or above then go for it. Can't imagine u'd get anywhere near that unless its a monster amp! Second question: yes, always put in a slighty lower fuse than the cable is rated for. The idea is that the fuse must be the weakest link in the chain. The amp should have a fuse in one of its panels that will give u an idea of the cable (and thus fuse) size u will need to run it.

[Mike1990]

Thank you, you have been a great help.

[mechsman]

No worries m8.