Programming
890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames B, C & D
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POWER LOSS CNTRL
SETUP::MOTOR CONTROL::POWER LOSS CNTRL
Designed for all Motor Control Modes.
This function block controls the behaviour of the drive during a power outage.
When enabled, the drive attempts to keep the dc link high by regeneratively recovering the kinetic energy in the motor load in
the event of mains supply loss.
This is achieved by ramping the speed setpoint to zero during the power outage. If during the outage the supply returns, the
speed setpoint is automatically ramped back to the speed setpoint.
When disabled, the drive will trip on UNDERVOLTS if the mains supply is removed.
Parameter Descriptions
ENABLE
PREF: 112.01
Default: FALSE
Range: FALSE / TRUE
When TRUE, the Power Loss Ride-Through functionality is enabled.
TRIP THRESHOLD
PREF: 112.02
Default: 243V
Range: 0 to 1000 V
Determines the dc link volts at which the Power Loss Ride-Through sequence is triggered.
CONTROL BAND
PREF: 112.03
Default: 20 V
Range: 0 to 1000 V
Sets the dc link voltage above the TRIP THRESHOLD at which the setpoint Ramp to Stop is paused. If the dc link volts remain
above this level for a period greater than 500ms, the setpoint is ramped back to the speed demand.
ACCEL TIME
PREF: 112.04
Default: 10.00 s
Range: 0.01 to 300.00 s
Determines the time in which the speed setpoint is ramped back to the speed demand. This is expressed as the time to ramp from
zero to MAX SPEED.
