question

rjoustra avatar image
rjoustra asked

Battery wiring

So my system currently has two inverters with equal cable lengths tied to blue sea 1000 amp buss bars. My question is on the battery side currently I have 10 BB100 batteries. I have ordered two large 460 ah batteries to eliminate all my incorrect cables, reduce space and weight in my RV. My question is about cable lengths on the battery side, for orientation sake and to utilize the shortest possible cables I would end up with 1 battery having a long positive and a short negative cable and just the opposite for the other. The round trip would be the same and both batteries have their own 400 amp fuses and disconnects, then landing on the same buss bars as the inverters. Is this going to result in a charging or discharging imbalance. Again the round trip cable lengths will be almost identical considering they go through a shunt and fusing and disconnects. Thoughts?

battery chargingLithium Battery
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3 Answers
Sebastian avatar image
Sebastian answered ·

If the sum of positive and negative cable lengths is the same on the batterys, the voltagedrop is the same on bouth. What can be a problem is, when the common is connected through the BMS communication cable (if there is a BMS in the batterys itself)

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rjoustra avatar image
rjoustra answered ·

So yes these batteries are the new EPOCH 460ah with compatibility for victron DVCC communication built in BMS. Would it be better than to sacrifice orientation and some cable length to keep the 2 positive the same and the 2 negative the same?

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Sebastian avatar image
Sebastian answered ·

If there is a voltagedifference from the two negative poles, a current could flow on the BMS Cable.
This is only, then there is no isolation between the Bus and negative.

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