Hello;

We changed our defective Micromaster 430 400V 250kW driver to Sinamics G120 with same values. We are using it for driving cooling fan motor of glass tempering furnace. It is working now but we are worried about ramp currents. Nominal motor current is about 440 Amps but when motor loaded and accelerates/decelerates without stops, current value gets nearly 600 Amps. Within a little time, it returns normal values (about 430-440 amps) but i think it can work without current overshoots. What can i do to normalize it? We are awaiting your help.

Thanks in advance. 

which is CU unit?

Which is cotrol method/type? V/F or SLVC or VC?

IN V/F mode, which mode, linear or FCC etc.etc.?

If it not linear, have you set correct voltage/frequeency points along a characteristic. In MM440 it has 3 points & in G120 it has 4 points. So please the values of it.