Special Starting - Using Dual Settings - Wiring Diagram; Choosing A Suitable Pump Curve (Centrifugal Pumps); Starting Curve - GE ASTAT XT QT 0008U Series User Manual

Solid state soft starter
Table of Contents
Special Starting – Using DUAL Settings – Wiring Diagram
6.2.3.1

Choosing a Suitable Pump Curve (Centrifugal Pumps)

6.2.4

Starting Curve

6.2.4.1
Adjust Main Settings as necessary (Starter Current, Motor Current, etc.).
Set Soft Starting Curve, Ramp UP Time, Current Limit, and Starting Voltage to their default
values (curve 0, 10 sec., 400% and 30% respectively).
Start the pump while watching the pressure gauge as the pump starts and look for overshooting ("pressure surge")
of the gauge needle above the target pressure. In case of over pressure, choose a peak torque reduction curve
(Soft Start Curve 1!!).
Set Soft Start Curve 1!!, increase Ramp UP Time to 15 seconds and reduce Current Limit to 350%.
Start the pump and watch the pressure gauge while the pump starts.
In most cases overshooting is reduced. If the overshoot persists, increase Ramp UP Time to 25 seconds (confirm
with the motor manufacturer) and try again.
If overpressure persists, increase the Soft Start Curve setting to 2!! or 3!! if necessary. Each increase in
the Soft Start Curve setting will reduce the peak torque, thus reducing the overpressure and preventing
"pressure surge" during start.
• Starting Procedure
57
Table of Contents
loading

Table of Contents