This eight-page product leaflet presents ABB's PSS, PST and PSTB softstarters. It explains why soft start is used, compares direct-on-line and star-delta starting, gives a quick selection guide, and lists PSS and PST models with rated currents, fuse protection, contactors and overload relays.
The leaflet also describes the PSS compact and flexible ranges and the PST advanced range, including the LCD display, four-button keypad, external keypad, integrated motor protection and FieldbusPlug communication. It notes that PSTB370 to PSTB1050 units have an integrated by-pass contactor.
| Inside-delta current reduction | 42 % |
|---|---|
| External keypad protection degree | IP66 |
| PST display languages | 12 |
| Available fieldbus protocols | AS-Interface, DeviceNet and Profibus DP |
| Integrated by-pass contactor sizes | PSTB370...PSTB1050 |
| Programmable signal relays per PST unit | Three |
| PSS start ramp setting range | 1-30 sec |
ABB's PSS and PST softstarters ensure a gradual voltage increase during start-up, which naturally limits the current.
Yes. PSS18/30...300/515 and PST30...300, PSTB370...1050 can be connected inside the motor delta, where the current through the softstarter is reduced by 42 %.
AS-Interface, DeviceNet and Profibus DP are available through the ABB FieldBusPlug.
The external keypad fulfills the protection degree IP66.