Operating Instructions

Fault Codes
Digital Keypad
315 | 443
ID*
Display on LCD Keypad
Fault Name
Fault Descriptions
21
Over load (oL)
● The AC motor drive detects excessive drive output current.
● Overload capacity:
● Normal duty:
● Sustains for one minute when the drive outputs 120% of the
drive’s rated output current.
● Sustains for three seconds when the drive outputs 150% of the
drive’s rated output current.
● Heavy duty:
● Sustains for one minute when the drive outputs 150% of the
drive’s rated output current.
● Sustains for three seconds when the drive outputs 200% of the
drive’s rated output current.
Action and Reset
Action level
Based on overload curve and derating curve (See Section 9-7).
Action time
When the load is higher than the protection level and exceeds allowable time, the oL protection
activates.
Fault treatment parameter
N/A
Reset method
Manual reset
Reset condition
Reset in five seconds after the fault is cleared
Record
Yes
Cause
Corrective Actions
The load is too large
Reduce the load
Accel./Decel. time or the working cycle are
too short
Increase the setting value for Pr.01-12–01-19 (accel./decel. time)
V/F voltage is too high
● Adjust the settings for Pr.01-01–01-08 (V/F curve), especially the setting value for the mid-
point voltage (if the mid-point voltage is set too low, the load capacity decreases at low
speed).
● See the V/F curve selection of Pr.01-43.
The capacity of the drive is too small
Replace the drive with a larger capacity model.
Overload during low-speed operation
● Reduce the load during low-speed operation.
● Increase the drive capacity.
● Decrease the carrier frequency of Pr.00-17.
Torque compensation is too large
Adjust the torque compensation (See Pr.07-26 Torque Compensation Gain) until the output
current reduces and the motor does not stall.
Check if the setting for stall prevention is
correct.
Set the stall prevention to the proper value.
Output phase loss
● Check the status of three-phase motor.
● Check if the cable is broken or the screws are loose.
Improper parameter settings for the speed
tracking function (including restart after
momentary power loss and restart after
fault)
● Correct the parameter settings for speed tracking.
● Start the speed tracking function.
● Adjust the maximum current for Pr.07-09 speed tracking.