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acuario avatar image
acuario asked

Strange AC load values from Quattro with no load connected

I have a Quattro 48/5000 connected to a Cerbo and am getting some very odd results that don't make sense on both the web console and Modbus-TCP.

There is no load connected to the Quattro.

Scenario 1: Quattro powered by batteries

Console displays AC load as 0 which is correct.
Modbus register 817 (from the Cerbo) shows 00 00 (0W) which is correct
Modbus register 23 (from the Quattro) shows FF FE (-32767W) which seems wrong!


Scenario 2: AC in 1 to Quattro with 220VAC, Quattro in Passthru

Console displays AC load as between 100W and 103W
Modbus register 817 (from the Cerbo) shows 00 64 (100W) which is wrong as there is no load
Modbus register 23 (from the Quattro) shows 00 0A (10W) which is wrong as no load


Why is the system showing an AC load when there obviously isn't one and why is there a discrepancy between the Quattro Output power and Cerbo AC consumption?

MultiPlus Quattro Inverter Chargercerbo gxModbus TCP
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1 Answer
Mike Dorsett avatar image
Mike Dorsett answered ·

"Modbus register 23 (from the Quattro) shows FF FE (-32767W) which seems wrong!"

in 2's complement this is -1W, which is ok.

in the 2nd scenario, you are probably looking at the self consumption power, one is AC in at ~100W, the other is AC out which is measuring a little stray load - 10W. this is ~0.2%, which is the basic accuracy of the measuring system.

Hope this helps.

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