65 • Control Keypad
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7.8.3.1
Soft Start Parameters
The HRVS-DN incorporates five starting curves to enable you to select a suitable torque curve.
SOFT START CURVE 1
– Standard curve (Default). This curve is the most suitable curve for preventing
prolonged starting and motor overheating.
SOFT START CURVE 2-4 -
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 pressure surge in
the pipes.
SOFT START CURVE 2, 3, 4 – 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: 1!, 2!, 3!, 4!
SOFT START CURVE 5 (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 1. If towards the end of acceleration peak torque is too high (pressure
is too high) proceed to Curve 2, 3, 4 or 5 in that order.
SOFT START CURVE 0
– Basic curve. This curve uses less feedback signals. Use this curve if other curves
do not give good results.
WARNING!
When operating in SOFT START CURVE 0 motor must be loaded, otherwise,
vibration may occur towards the end of the soft start process.
