Chapter 14 Fault Codes and DescriptionsME300
14-1
Chapter 14 Fault Codes and Descriptions
ID No. Display on LCM Keypad Fault Name Fault Descriptions
1
Over-current during
acceleration
(ocA)
Output current exceeds 2.5 times of the rated current
during acceleration. When ocA occurs, the drive closes
the gate of the output immediately, the motor runs freely,
and the display shows an ocA error.
Action and Reset
Action level 250% of the rated current (software)
Action time Immediately act
Fault treatment parameter N/A
Reset method Manual reset
Reset condition Reset in 5 sec. after the fault is cleared.
Record Yes
Cause Corrective Actions
Acceleration time is too short.
1. Increase the acceleration time
2. Increase the acceleration time of S-curve
3. Set auto-acceleration and auto-deceleration parameter (Pr.01-44)
4. Set over-current stall prevention function (Pr.06-03)
5. Replace the drive with a larger capacity model
Short-circuit at motor output due to
poor insulation wiring.
Without considering the short circuits, check the motor cable or replace the
cable before turning on the power.
Check for possible burnout or
aging insulation of the motor
Check the motor insulation value with megger. Replace the motor if the
insulation is poor.
The load is too large.
Check if the output current during the whole working process exceeds the
C
motor drive’s rated current. If yes, replace the AC motor drive with a larger
capacity model.
Impulsive change of the load Reduce the load or increase the capacity of the AC motor drive.
Use special motor or motor with
larger capacity than the drive
Check the motor capacity (the rated current on the motor’s nameplate should ≤
the rated current of the drive)
Use ON/OFF controller of an
electromagnetic contactor at the
output (U/V/W) of the drive
Check the action timing of the contactor and make sure it is not turned ON/OFF
when the drive outputs the voltage.
V/F curve setting error
Adjust V/F curve settings and frequency/voltage. When the fault occurs, and the
frequency voltage is too high, reduce the voltage.
Torque compensation is too large.
Adjust the torque compensation (refer to Pr.07-26 torque compensation gain)
until the output current reduces and the motor does not stall.
Malfunction caused by interference
Verify the wiring of the control circuit and wiring/grounding of the main circuit to
prevent interference.
The motor starts when in free run. Enable the speed tracking during start-up of Pr.07-12.
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.
1. Start the speed tracking function.
2. Adjust the maximum current for Pr.07-09 speed tracking.
Incorrect combination of control
mode and used motor
Check the settings for Pr.00-11 control mode:
1. For IM motor, Pr.00-11=0, 2, Pr.05-33=0
2. For PM motor, Pr.00-11=2, Pr.05-33=1, 2
The length of motor cable is too
long.
Increase the AC motor drive’s capacity.
Install AC reactor(s) on the output side (U/V/W).
Hardware failure
The ocA occurs due to short circuit or ground fault at the output side of the drive.
Check for possible short circuits between terminals with the electric meter:
B1 corresponds to U, V, W; DC- corresponds to U, V, W;
corresponds to U,
V, W.
If short circuits occur, return to the factory for repair.
Check if the setting for stall
prevention is correct.
Set the stall prevention to the proper value.