Battery Cable Fuse Size, Newbie need help!

[sharp230]

Hello All,

I am setting up a 24 volt solar system with (4), 230 watt solar panels, total AMPS(31.4). 60 Amp MS-Charge Controller, Samlex-1000 watt 24 volt Inverter, with (8), 6 volt 200 ah AGM batteries (serial/parallel) with 4/0 awg cables. I have #4 awg wire from c.c. (75 amp fuse) and inverter (80 amp fuse). Also a Bogart trimetric battery monitor.
My question is, what size fuse is needed for battery bank cable? Any and all help is appreciated!
Thanks to all in advance!!
sharp230

[inetdog]

Hello All,

I am setting up a 24 volt solar system with (4), 230 watt solar panels, total AMPS(31.4). 60 watt MS-Charge Controller, Samlex-1000 watt Inverter,
with (8), 6 volt 200 ah AGM batteries (serial/parallel) with 4/0 awg cables. I have #4 awg wire from c.c. (80 amp fuse) and inverter (75 amp fuse).
My question is, what size fuse is needed for battery bank cable? Any and all help is appreciated!

Thanks to all in advance!!
sharp230

The inverter fuse seems to be a little small, since 75A times 12V only gives you 900 watts.
But, leaving that aside, if the inverter is your only load a slightly larger fuse on the battery side (say 100A) should work just fine.
Looking at it a different way, if a fault should develop between the battery terminals and either of the fuses you mention, the battery fuse only needs to be sized to protect the 4/0 wire. That wire (assuming copper) can easily handle 200A. So any fuse size up to 200A will be fine.

[sharp230]

The inverter fuse seems to be a little small, since 75A times 12V only gives you 900 watts.
But, leaving that aside, if the inverter is your only load a slightly larger fuse on the battery side (say 100A) should work just fine.
Looking at it a different way, if a fault should develop between the battery terminals and either of the fuses you mention, the battery fuse only needs to be sized to protect the 4/0 wire. That wire (assuming copper) can easily handle 200A. So any fuse size up to 200A will be fine.

Thanks a lot Inetdog, for your help! certainly needed and appreciated. You were right, as I noticed later that the C.C is 75 Amp, and Inverter 80 Amps.
what the manual calls for. Don't know how much of a difference it make.

Thanks again,