Chapter 6 Fault Code Information and Maintenance 
 VFD-EL-W 
6-2 
 
6.1 Fault Code Information 
The following messages display when the operation command source is set as digital keypad.
 
Fault Name  Fault Descriptions  Corrective Actions 
 
Over-current 
Abnormal increase in current. 
1.  Check if the motor power corresponds with the AC 
motor drive output power. 
2.  Check the wiring connections to U/T1, V/T2, and 
W/T3 for possible short circuits. 
3.  Check the wiring connections between the AC motor 
drive and motor for possible short circuits, and for 
short to ground. 
4.  Check for loose contacts between the AC motor drive 
and the motor. 
5.  Increase the Acceleration Time. 
6.  Check for possible excessive loading on the motor. 
 
Over-voltage 
The DC bus voltage exceeds its 
maximum allowable value. 
1.  Check if the input voltage is in the rated AC motor 
drive input voltage range. 
2.  Check for possible voltage transients. 
3.  DC bus over-voltage may also be caused by motor 
regeneration. Either increase the Deceleration Time 
or add an optional brake resistor (and brake unit). 
 
Overheating 
Heat sink temperature is too high. 
1.  Ensure that the ambient temperature is in the 
specified temperature range. 
2.  Make sure that the ventilation holes are not 
obstructed. 
3.  Provide enough spacing for adequate ventilation. (see 
Chapter 1) 
 
Low voltage 
The AC motor drive detects that 
the DC bus voltage has fallen 
below its minimum value. 
1.  Check whether the input voltage is in the AC motor 
drive rated input voltage range. 
2.  Check for abnormal load on the motor. 
3.  Check for correct input power wiring to R-S-T (for 
three-phase models) without phase loss. 
 
Overload 
The AC motor drive detects 
excessive drive output current. 
NOTE: The AC motor drive can 
withstand up to 150% of the rated 
current for a maximum of 60 
seconds. 
1. Check whether the motor is overloaded. 
2.  Reduce the torque compensation setting (Pr.07.02). 
3.  Use the next higher power AC motor drive model. 
 
Overload 1 
Internal electronic overload trip 
1.  Check for possible motor overload. 
2.  Check the electronic thermal overload setting. 
3.  Replace the drive with a larger capacity model. 
4.  Reduce the current level so that the drive output 
current does not exceed the value in the Motor Rated 
Current (Pr.07.00). 
 
Overload 2 
Motor overload. 
1. Reduce the motor load. 
2. Adjust the over-torque detection settings to 
appropriate values (Pr.06.03–Pr.06.05). 
 
CC (current clamp)  Return the unit to the factory. 
 
OV hardware fault 
Return the unit to the factory. 
 
OC hardware fault