Chapter 14 Fault Codes and DescriptionsME300 
 
14-13
Record  When Pr.06-06=2 or 4, ot1 is a “Fault”, and the fault is recorded. 
Cause  Corrective Actions 
Incorrect parameter setting  Reset Pr.06-07 and 06-08. 
Mechanical error (e.g. over-torque, 
mechanical lock) 
Remove the causes of malfunction. 
The load is too large. 
Reduce the load. 
Replace the motor with a larger capacity model. 
Accel./Decel. time and working 
cycle are too short. 
Increase the setting values for Pr.01-12–01-19 (accel./decel. time). 
V/F voltage is too high. 
Adjust 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). 
Refer to the V/F curve selection of Pr.01-43. 
The motor capacity is too small.  Replace the motor with a larger capacity model. 
Overload during low-speed 
operation. 
Decrease low-speed operation time. 
Increase the motor capacity. 
Torque compensation is too large. 
Adjust the torque  compensation (refer to  Pr.07-26 torque compensation  gain) 
until the current reduces and the motor does no stall. 
Improper parameter settings for 
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. 
 
ID No.  Display on LCM Keypad  Fault Name  Fault Descriptions 
27 
 
Over-torque 2   
(ot2) 
When output current exceeds the over-torque detection 
level (Pr.06-10) and exceeds over-torque detection time 
(Pr.06-11), and when Pr.06-09 is set to 2 or 4,  the ot2 
error displays. 
Action and Reset 
Action level  Pr.06-10 
Action time  Pr.06-11 
Fault treatment parameter 
Pr.06-09 
0: No function 
1:  Continue  operation  after  over-torque  detection  during  constant  speed 
operation 
2: Stop after over-torque detection during constant speed operation 
3: Continue operation after over-torque detection during RUN 
4: Stop after over-torque detection during RUN 
Reset method 
Auto 
When  Pr.06-09=1  or  3,  ot2  is  a  “Warning”.  The  warning  is 
automatically cleared when the output current < (Pr.06-10 – 5%). 
Manual  When Pr.06-09=2 or 4, ot2 is a “Fault”. You must reset manually. 
Reset condition    Immediately reset 
Record  When Pr.06-09=2 or 4, ot2 is a “Fault”, and the fault is recorded. 
Cause  Corrective Actions 
Incorrect parameter setting  Reset Pr.06-10 and Pr.06-11. 
Mechanical error (e.g. over-torque, 
mechanical lock) 
Remove the causes of malfunction. 
The load is too large. 
Reduce the load. 
Replace the motor with a larger capacity model. 
Accel./Decel. time and working 
cycle are too short. 
Increase the setting values for Pr.01-12–01-19 (accel./decel. time). 
V/F voltage is too high. 
Adjust the settings for Pr.01-35–01-42 (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). 
The motor capacity is too small.  Replace the motor with a larger capacity model. 
Overload during low-speed 
operation 
Decrease low-speed operation time. 
Increase the motor capacity. 
Torque compensation is too large. 
Adjust  the  torque  compensation (refer  to  Pr.07-26  torque  compensation  gain) 
until the current reduces and the motor does no stall. 
Improper parameter settings for 
speed tracking function (including 
restart at 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.