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sven-1 asked

VRM dashboard numbers don't add up

1628613841833.png

From this screen shot, the inputs and outputs do not even closely add up. The house is consuming 9kW, the solar is hardly generating, the battery is charging although at -5.5kW, and the grid meter is showing feeding back to the grid at 1.6kW.

This is a 3-phase installation with 3 5kVA multiplus II, one per phase.

Phase rotation maybe?


VRM
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shaneyake avatar image shaneyake commented ·

What kind of meter are you using? Possibly the CT is backwards on L2? If L2 is reversed the numbers mostly add up within some margin.
The battery is discharging in this screenshot, the label may not have switched yet.

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sven-1 avatar image sven-1 shaneyake commented ·
ET340 3-phase meter is used.

Even when ignoring the label on the battery the numbers still don't add up.

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shaneyake avatar image shaneyake sven-1 commented ·


L1 (582 + 0) - 178 = 404

L2 (2873+ 0) - 2836 = 37

L3 (1671 + 3778) - 982 = 4,467

404+37+4467 = 4,908 Total AC power
5536+47 = 5,583 Total DC Power
5583-4908 = 675w for inefficiencies and measurement timing accuracy doesn't seem that impossible to me however. I actually think your meter is backwards for all phases

L1 (582 + 0) + 178 = 760

L2 (2873+ 0) - 2836 = 37

L3 (1671 + 3778) + 982 = 6,431

5583-7,228= -1,645
If you reverse all your grid meter readings you will get that it is drawing in 1645W from the grid and then all your numbers add up to with in 31W which is definitely acceptable for 3phase system,

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sven-1 avatar image sven-1 shaneyake commented ·
Great reply thank you.

We actually figured it out, it was a phase rotation issue, which we resolved by swapping phase 2 and 3 between the main incomer and the grid meter, then reversing this for the 3-phase circuit breakers for the pumps. All sorted thank you.

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2 Answers
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sven-1 answered ·

We actually figured it out, it was a phase rotation issue, which we resolved by swapping phase 2 and 3 between the main incomer and the grid meter, then reversing this for the 3-phase circuit breakers for the pumps. All sorted thank you.

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Willem avatar image
Willem answered ·

1690130011638.png


These also dont add up


103-12-22 =69 Watt difference during the day with PV available even bigger diference's are experianced


Multiplus II 5 KVA , Cerbo GX , ET112 , Freedom Won e-tower bateries(2)


what can be the reason ?


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