I have three 5.12kw batteries with Deye 8kw inverter. If no PV is available, the batteries wil only give 2.6kw power,else the system shuts down (get DC volt low error). All batteries are fully charged, connected via comms cable and ADD switches set as Shoto setup. Inverter settings setup as instruction booklet.

Should I not get as per Shoto 4.6kw per battery x3 =13.8kw?Or at least 8kw usable since inverter is 8kw. Is there setting somewhere not correct?

I am no authority on batteries.. but my understanding is that from a capacity perspective, i work on rated power minus 20% (this would depend on when the battery cuts off per lower limit.. eg. If your cutoff is 20%, it gives you 80% useable output). So that gives around 4kwh per battery. More or less depending on your cutoff. 

I have a single one of these batteries and it gives me the expected output between fully charged and 30%. In my case it never goes below 30%, this is where mine cuts off. 

I dont know that the output rating of the inverter affects it. I think the 8kw rating is more total output at any given time. Not cumulative power.. if that makes sense. Hopefully someone with more experience and knowledge can add to this if my view is incorrect.

 

Question. When your batteries cutoff, have you noticed an alarm light on the batteries? If yes, is it on all the batteries? Or just one of them?

Edited March 18, 20224 yr by GTP
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