Hallo,

I have few DCM's working as multimotor drives. Each one drives 6 to 12 motors connected in paralel. Speed feedback is from EMF. I noticed EMF spikes which are irregular on all drives. Some Times this spikes trigger fault F60043 EMF for braking operation too high , in another case trigger F60038 (N, A) Overspeed threshold overshot.

Does anyone have any idea what is the reason, or how to avoid faults ?

It happens witout or with load, with stable low setpoint in negative direction of rotation only (at least only in this case I have this faults). In attachment is trace of EMF with this spike.

Regards,

Maciek

Very long, about 300m. but there are DC output air reactors.

All rollertable sections have the same lenght of cables, but this fault happens only on three of them.

Some rollertables are driven by old DC Masters, and there is also NO problem, only on 3 of 11 problem occure.