ACOPOS UDC_ACT breakdown after about 2min with constant torque and velocity

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1

Hi there,
We are confronted with a phenomenon where after a while (about 2min) on constant speed and torque the ACOPOS-P3 UDC_ACT (= the DC-BUS Voltage) breaks down.

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If we run the motor with 1000rpm all parameters remain OK.
If we run the motor with about 1200rpm the UDC breaks down after a while.

The main power-supply 3x400V 64A is also OK and stable what we know now.

Question: Does anyone have a idea what might be the root cause of this breaking down UDC?

We stuck right now… Thanks a lot!

2

I would expect that the supply on the Acopos terminals goes directly to the rectifiers to create the DC Bus Voltage. So either you’re drawing more current than can be rectified and smoothed (unlikely) or the supply to the Acopos is throttled or isn’t stable. Check the supply cabling for correct size and tight connection.
I’d suggest clamping an Amperemeter to each one of the phases in turn (one by one).