Delta Electronics VFD-F Series User Manual

 

DELTA ELECTRONICS, INC. ALL RIGHTS RESERVED 

7-1

 

The AC drive has a comprehensive fault diagnostic system that includes several 
different alarms and fault messages. Once a fault is detected, the corresponding 
protective functions will be activated. The following faults are displayed as 
shown on the AC drive digital keypad display. The four most recent faults can be 
read on the digital keypad display. 

 
NOTE: Faults can be cleared by a reset from the keypad or Input Terminal. 
 
Common Problems and Solutions: 

 

The AC drive detects an 
abnormal increase in 
current. 

1.  Check whether the motors horsepower 

corresponds to the AC drive output 
power. 

2.  Check the wiring connections between 

the AC drive and motor for possible 
short circuits. 

3.  Increase the Acceleration time. 
4.  Check for possible excessive loading 

conditions at the motor. 

5.  If there are any abnormal conditions 

when operating the AC drive after 
short-circuit being removed, it should be 
sent back to manufacturer. 

 

The AC drive detects 
that the DC bus voltage 
has exceeded its 
maximum allowable 
value. 

1.  Check whether the input voltage falls 

within the rated AC drive input voltage.   

2.  Check for possible voltage transients. 
3.  Bus over-voltage may also be caused by 

motor regeneration. Either increase the 
decel time or add an optional brake 
resistor.  

4.  Check whether the required brake power 

is within the specified limits.