Our digital Soft Starters line of products ISA-D, ISA-DS, ISA-HD provide an advanced microprocessor based control algorithm, enabling the sophisticated pump control feature. The motor torque is continuously monitored to eliminate peak torque from stressing the motor, pump and pipe system. These soft starters provide 3 field selectable pump control algorithms.
Pump and special load control
Two major problems are associated with starting and stopping of pumps.
Over-pressure during starting
The sharp increase of torque towards the end of acceleration can cause high pressure and damage the pipe system. The pump control enables selection between three voltage ramp-up curves as well as torque curve to reduce peak torque. Current ramp is available for special loads.
Water hammer during stopping
During soft stop, when voltage is decreasing, motor torque may fall below load torque causing abrupt stalling instead of smoothly decreasing speed to zero. This creates the "water hammer" phenomenon (resulting in a loud noise and damage to the pipe system). The pump control algorithm enables selection between three voltage ramp-down curves of torque curve preventing stall condition and eliminating water hammer.
|
