question

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pchristou asked

Unwanted switch over when there's sudden high load demand


As you can see in the image below, when there is a sudden high load demand, the ESS system switches over and supplies the loads from the AC grid, not from the battery which at that time is sufficiently charged. At that time, a small voltage drop occurs on the battery side. Could it be due to a voltage drop on the battery cables, which are 12-13 meters long and 70mm?


The VE.Bus System is Quattro 48/15000/200-2x100.

The Solar charger is SmartSolar MPPT RS 450/200.

1684235654962.png


ESSbatteryswitch
1684235654962.png (126.7 KiB)
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1 Answer
Alexandra avatar image
Alexandra answered ·

@pchristou

Yes, your battery cables are way too small for both the 15kva and for the length.

Look in the manual. It is 2x95mm² for under 5m length. You will need to go much larger for your run. 2x 150mm² positive and negative.

The voltage on the mppt says it all. What is the voltage at the ve bus terminals?

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