GE ASTAT XT QT 0008U Series User Manual page 33

• Control Keypad
33
Soft Start Curves 1-3 - Pump Control - Induction motors produce peak torque of up to 3 times the rated
torque towards the end of starting process. In some pump applications, this peak may cause a pressure surge in the
pipes.
Soft Start Curves 1, 2, 3 – During acceleration before reaching peak torque, the Pump Control Program
automatically controls the voltage ramp-up, thus, reducing peak torque.
Choice of four pump control acceleration curves: 0!, 1!, 2!, 3!
Soft Start Curve 4 (Torque) – Torque Controlled acceleration - This provides a smooth time-controlled
torque ramp for the motor and the pump.
Note:
Always start with Soft Start Curve 0. If towards the end of ramp, peak torque is too high (pressure is too high)
proceed to Soft Start Curve 1, 2, 3 or 4 in that order.