Bedford B550-2001, Installation And Quick Start Manual

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5-10
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 Factory Setting: 00
Settings 00 to 100% Unit: 1%
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.
Pr.29
DC Braking Time during Start-up Factory Setting: 0.0
Settings 0.0 to 5.0 sec Unit: 0.1sec
This parameter determines the duration for the DC Braking Current applied during
starting. DC Braking is applied until the Minimum Frequency is reached.
Pr.30
DC Braking Time during Stopping Factory Setting: 0.0
Settings 0.0 to 25.0 sec Unit: 0.1sec
This parameter determines the duration for the DC Braking voltage to be applied during
stopping. If stopping with DC Braking is desired, then Pr.02 must be set to Ramp to
Stop (0.0).
B550
Series
sensorless vector frequency drive