I my plant we have a rectifier for electrolytic cleaning. 7500A and
30V(Max). We give the reference for current. The problem is when we measure the current through out PLC analog channel we find it fluctuating. The current waveform exactly follows the voltage waveform. The configuration is 2 half wave 3-phase rectifiers working in paralle through the interphase transformer. Should I add something to get an steady feedback. I suspect the fluctuation has to do with the scanning of the AI channel of the PLC. we should send the coltage as DC without harmonics rather than the way it is now.- posted
15 years ago