Soft starter ABB Series PSR

Functional Description

Asynchronous motors are often started directly or with a star-delta circuit. During direct start, extremely high start-up currents occur, up to seven times the rated motor current. The star-delta circuit mitigates the problem by providing a root-3 lower phase voltage. However, switching from star to delta also produces a significant current spike. These starting methods can overload the network, disturb other consumers, cause mechanical problems, and expose the entire drive to high wear.

The solution to these problems is a soft starter. During start-up, the starter reduces the voltage in two of the three phases using phase control. During the adjustable start-up time, the torque increases slowly until full line voltage is applied to the motor. This results in a network and drive-friendly, jerk-free ramp-up of your drive.

The PSR series includes the most compact soft starters, allowing for the design of compact starting devices. The system concept with motor protection switches and the products from the PSR series provides a significantly more compact starting solution than, for example, a star-delta starter.

Integrated bypass relays reduce energy losses and simplify the connection; the setup is incredibly easy thanks to the restrictions to only three potentiometers. The optimized ramp characteristics ensure very smooth acceleration and deceleration under all operating conditions.

Settings - see image under Downloads

1 = Start 1...20s

2 = Deceleration 0...20s - including step voltage

Step voltage = decrease by 2% for each second of increased stop ramp

Stop ramp: 10s -> Step voltage 80% (20% reduction)

3 = Uini = 40...70% results in final voltage 30...60%