Rockwell Automation 1557 MEDIUM VOLTAGE AC DRIVE - Manual (Page 83)

PARAMETER AND VARIABLE DESCRIPTIONS 6-27
1557-UM050F-EN-P – June 2013
Ground Fault Overvoltage Delay [Gnd flt O/V dly]
Linear number:
190
Minimum value: 0.000 sec
Maximum value: 5.000 sec
Default value: 0.500 sec
This parameter specifies the time the motor neutral to ground voltage must remain above the trip level before a
ground fault overvoltage is indicated.
Motor Stall Delay [Mtr stall delay ]
Linear number: 191
Minimum value: 0.00 sec
Maximum value: 10.0 sec
Default value: 2.00 sec
This parameter specifies the time the motor must be in a stall condition before a motor stall fault occurs. If the
tachometer option is enabled, the motor is considered to be stalled if the drive is in torque limit at any speed
less than 1 Hz. If the tachometer option is not enabled, the motor is considered to be stalled if the drive is at
commanded speed and the motor flux is below the level specified by parameter “Flux minimum”. A stall cannot
be detected until the drive reaches the commanded speed because the motor may already be rotating when
the drive is started. In this case, if the motor speed is above the commanded speed, or the motor is rotating in
the opposite direction, a stall fault will occur.
V Stator Minimum Thyristor Fault [Vs min thy fault]
Linear number:
192
Minimum value: 0.10 pu
Maximum value: 0.50 pu
Default value: 0.25 pu
This parameter specifies the minimum stator voltage required for detection of machine converter thyristor
faults. If the drive is incorrectly detecting motor thyristor faults while running (not while starting), increasing this
parameter may eliminate the problem.
This parameter was added in Rev 5.10 and is not present in 4.xx.