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phemens's avatar
phemens
Explorer
Aug 28, 2019

Bus Bars - 150A rated ok?

Have 500AH battery (LIFePO4) and a 3000 watt Samlex inverter. Wiring is all going through bus bars. I made an order to get new ones, received Blue Seas 4 post rated at 150 amps. I thought I had ordered rated at 250 amp. Question is, do I really need to go to 250 amp (return and re-order) - what's my risk? Real world high draw use is occasional microwave, coffee maker, etc.

Other question is, I originally had 4x100 AH batteries all wired with 00 gauge welding wire. To add the new 5th one (bought within a few months of the others), I have some spare 0000 wire to make the cable (all wiring from batteries to bus bar is same length), ok to use or do I really need to find some 00 to make everything uniform?

45 Replies

  • phemens wrote:
    , is there any significant impact in having one battery wired to the bus with 4/0 where the other 4 are all 2/0 (all wire lengths being equal, only variance is gauge)
    Now I remember.. you're wiring each battery separately to the busbar. Each battery contributes 1/5 of the required amps, in theory, so I wouldn't worry about the 4/0 thing..other than the hassle of working with it.
  • I'm ok for the 5 in parallel, yes, mfg confirmed.
    I know only the inverter needs the 4/0, which it does. To clarify, my question is: in real-world situation, is there any significant impact in having one battery wired to the bus with 4/0 where the other 4 are all 2/0 (all wire lengths being equal, only variance is gauge)

    Ok, I will bite the bullet on the higher amperage bus bars
  • My 3000 watt inverter tops out at over 270 amps. Return and reorder.
  • Depends on the voltage. Some mfrs recommend paralleling only 4 max. Is that your case?

    Assuming 12v, only the inverter connections need to be 4/0.
  • Remember that business with the fuses, where the total of all the various branch ampacities to the bus bar has to be equaled by the ampacity of the single main fat wire from the bus bar.

    So obviously the bus bar itself has to have that total ampacity too.

    Can't say about the fifth battery wiring. Lost track of that.

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