Danfoss 176F7300, Manual, Page: 31 / 90

VLT ® MICRO
During periods of rapid acceleration or excessive load, the AC drive output current may
increase abruptly and exceed the value specified by Pr.26. When this function is
enabled, the AC drive will cease to accelerate, then maintain a constant output
frequency. The drive will only resume acceleration when the current drops below the
preset value.
Pr.27 Over-Current Stall Prevention During Operation
Factory Setting d170%
Units 1%
Parameter value d50 - d200%
During steady-state operation with the motor load rapidly increasing, the AC drive output
current may exceed the limit specified in Pr.27. When this occurs, the output frequency
will decrease to maintain a constant motor speed. The drive will accelerate to the
steady-state operating frequency only when the output current drops below the level
specified by Pr.27. A setting of 100% is equal to the rated current of the drive.
Pr.28, Pr.29, Pr.30, Pr.31 – DC Braking Current
Pr.28 DC Braking Current
Factory Setting d00%
Units 1%
Parameter value d00 - d100%
This parameter determines the DC current that will be applied to the motor during
braking when the Motor Stop Method (Pr.02) is programmed to "Ramp Stop". The DC
braking current is set at increments of 1%. A setting of 100% is equal to the rated
current of the drive.
NOTE: When setting this parameter, begin at a lower current level, then increase the
value until sufficient holding torque is achieved. The rated motor current should not be
exceeded.
Output
current
Output
current %
Pr.26
Overcurrent
detection
level
Output
frequency
Time
Time
Stall prevention during acceleration Over-current stall prevention during operation
Time
Time
Output
frequency
Overcurrent
detection
level
Pr.27
29