Minimum Start Current - Danfoss VLT Pocket Manual

Minimum Start Current: What is the minimum start
current required by a soft starter?
Soft starters can limit start current to any specifi ed level, but the
practical minimum depends on the motor and load. Reducing the
start current reduces the torque produced by the motor, so the load
will stall if the start current is too low. In order to start successfully, the
motor must produce more acceleration torque than the load requires
throughout the start.
Successful start:
Unsuccessful start:
Start current can be estimated based on previous experience, or the
motor and load speed/torque curves can be analysed for a precise
calculation.
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VLT Soft Starter Pocket Guide 27