GE C11 Manuel D’Utilisation

-59- 

When the protective function is activated, drive output is instantly cut off (while the motor coasts until it is 

stopped), and an alarm is issued, and the details of the alarm are displayed on the keypad panel.

 

Table 6-1-1  List of Protective Functions  

Alarm Name 

Keypad 

panel dis-

play 

Contents of operation 

OC1 

During acceleration 

OC2 

During deceleration 

Overcurrent 

OC3 

While running at 
constant speed 

If the drive output current momentarily exceeds the over-

current detection level because of an overcurrent in the 

motor or the short-circuit in the output circuit, the output is 

shut down, an alarm is issued, and the drive is tripped. 

OU1 

During acceleration 

OU2 

During deceleration 

Overvoltage 

OU3 

While running at 
constant speed 

If the DC voltage of the main circuit exceeds the overvolt-
age detection level because of an increase in the regenerat-
ing current from the motor, etc., output is shut down, an 
alarm is issued, and the drive is tripped.  However, protec-
tion against inadvertent overvoltage loading (e.g., high-
voltage line) might not be provided. 

Undervoltage 

LU 

If the DC voltage of the main circuit falls below the undervoltage detection level 

because of a lowered power supply, output is shut down to protect the drive. If the 

restart function after momentary power failure is not activated, an alarm is issued 

and the drive is tripped. 

If the restart function is activated, the drive restarts automatically with no alarm. 

For further details of the protective function, refer to the descriptions of Function 

F14. 

Overheating of 
heat sink 

OH1 

If the temperature of the heat sink used for cooling the rectifier diodes and IGBTs 

rises because of cooling fan failure, etc., protective function is activated to stop 

operation, an alarm is issued, and the drive is tripped. 

External Alarm 

OH2 

If the control circuit terminal THR (functional change of X1 to X3 terminals) is 

set to OFF, an alarm is issued and the drive is tripped. 

Motor overload 

OL 

If the motor current exceeds the operating level set by the electronic thermal O/L 

relay, output is shut down to protect the motor, an alarm is issued, and the drive is 

tripped. 

Drive overload 

OLU 

If the output current exceeds the drive rated overload current, output is shut down, 

an alarm is issued, and the drive is tripped.