Battery to Bus wire size

[anne2263]

I have two LiFePo4 100 ah Batteries wired in parallel, using 2/0 cables. What size wire should I use to connect the batteries to the BUS bar? I will connect a 2000 watt inverter to this bar.
First build, clueless..

[chrisski]

When I’ve done voltage loss calculations for battery runs, usually voltage loss is negligible compared to what an ampacity chart says wire should be. All depends on voltage for your inverter whether 12 volt, 24 volt, or 48 volt. Here’s an ampacity chart:

044702F5-BB17-4F0F-B74A-BFFABF61DDA5.jpeg
A 2000 watt inverter ought to be on a 24 volt system.

[Mike90250]

Waiting to learn what your system voltage is. 2000w inverter should be on a 24V system and batteries sized to handle the expected loads. 100ah @ 24v is not a good match to a 2kw inverter.

[anne2263]

Thank you. My system is 12 volt. 2000 watt inverter. Inverter Lable reads: Input DC 11v-15v 200A 2400w and AC Output 115v 17.4 A.. Will it be ok to use the 2/0 AWG cable to connect inverter to BUS bar?

[Mike90250]

Thank you. My system is 12 volt. 2000 watt inverter. Inverter Lable reads: Input DC 11v-15v 200A 2400w and AC Output 115v 17.4 A.. Will it be ok to use the 2/0 AWG cable to connect inverter to BUS bar?

12V 2000w ( likely 3,000w peak)
3000/12= 250amps = 4/0 wire

2/0 wire is only rated to 175A

If there is much length, you may need larger wire to reduce voltage drop to prevent inverter shutdown from undervoltage.

https://lugsdirect.com/WireCurrentAmpacitiesNEC-Table-301-16.htm