How does Altistart ATS480 measure the torque?
The ATS480 calculates the motor torque based on the current, because when a motor has constant voltage and frequency, the amount of torque is directly proportional to the amount of current.
Rated torque is not defined in Altistart, so the torque value is only relative (referred to rated torque Tn)
This value of relative motor torque is used in function like motor underload monitoring (ULL), threshold set in LUL (underload threshold)