System with Multi RS 6000 and VM-3P75CT seems to oscillate

Hi,
i have 3 Multi RS 6000 and one VM3P75CT Meter in ESS Mode.
In the live view from the Meter in the GX Device i can see the current of each phase constantly swinging from -2A to 2A (faster then the refreshrate of the display) whilst the power ist nearly 0. Is this normal or an unwanted oscillation?

In VRM Portal Diagram it looks like this:

On the other phases its the same but with 1.0 and 1.4A current
BR

Hi @mode, this is normal behaviour. The current reported by the VM-3P75CT is the “RMS” current, which by definition is always positive. We chose to match the sign of this current to the sign of the real power value. So if the power is +0.1W, we report a positive current, but at -0.1W we report a negative current.

It seems you have quite a bit of reactive power in your system (power that doesn’t actually do any work), but still results in the flow of 2A RMS current. Also see section 6.3 of the Wiring Unlimited book. Since the Multi RS is regulating around the 0W setpoint, the sign of this RMS current flips continuously, but physically this doesn’t really mean anything. So no need to worry!

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