Delta Electronics VFD-M - Manual (Page 63)

Chapter 4 Parameters|
4-28 Revision May 2008, ME14, SW V3.04
Under certain conditions, the AC drive output current may increase abruptly, and exceed the
value specified by Pr.26. This is commonly caused by rapid acceleration or excessive load on
the motor. When this function is enabled, the AC drive will stop accelerating and maintain a
constant output frequency. Drive will resume accelerating only after the current drops below
the setting for Pr.26.
Pr.27 Over-Current Stall Prevention during Operation Unit: 1%
Factory Setting: 150%
Settings 20 to 200%
00: disable
During a 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
output frequency only when the output current drops below the setting for Pr.27.
Output current
over-current
detection
level
output
frequency
time
time
output current
over-current
detection
level
Pr.27
time
output
freq.
time
over-current Stall Prevention
during Acceleration Over-current Stall Prevention
during Operation
Pr.28 DC Braking Current Level Unit: 1%
Settings 00 to 100% Factory Setting: 00
This parameter determines the amount of DC Braking Current applied to the motor during
starting and stopping. When setting the DC Braking Current, please note that 100%
corresponds to the rated current of the AC drive. It is recommended to start with a low DC
Braking Current level and then increase it until proper holding torque has been attained.