FA172746
28 September 2021
Issue:A pump is oscillating (or surging) up and down when ramping up to speed on the ATS48 soft starter?
Product line:Altistart ATS48
Environment:All models, all serial numbers
Cause:Excessive motor slip
Resolution:In the drC menu, reduce LSC. Generally, LSC = 30 will suffice.
LSC = Stator Loss Compensation
Oscillations are most common when controlling a motor with excessive slip.
Another option is to turn off the torque control. In the drC menu, set CLP = OFF.
Refer to the ATS48 Programming manual S1A37491
