94
ACCELERATION
If the output current of the drive has reached Stall level during drive acceleration, the
drive will stop accelerating until the current level is reduced below Stall level before it
resumes acceleration to a set frequency command. See Fig. 5.3.10.
STEADY SPEED
If the output current of the drive has reached the Stall level during a steady speed
period, due to load fluctuation, the drive will then reduce its output frequency until the
output current level is reduced below Stall level. The drive will then increase its output
frequency to a set frequency command. See Fig. 5.3.11.
DECELERATION
If the DC BUS voltage reaches the O.V. fault level (800 VDC for the 460 VAC class,
400VDC for the 230 VAC class) during deceleration, the drive will stop further
deceleration until DC Bus voltage drops below the fault level. See Fig. 5.3.12.
Fig. 5.3.10: Stall Prevention during Acceleration
Fig. 5.3.11: Stall Prevention during Steady Speed
Output current
Output freq.
Stall prevention level [ADV: Code No. 39]
time
time
Output current
Output freq.
Stall prevention level [ADV: Code No. 39]
Dec. ramp
Acc. ramp
time
time
For more information contact: Sievert Crane and Hoist, (708) 771-1600, [email protected], www.sievertcrane.com
