Delta VFD-B Series

Revision April 2009, SW V1.00 7-1
Chapter 7 Troubleshooting
7.1 Over Current (OC)
ocA
ocd
OC
Ov er-curre nt
dur ing acceleration
Over-c ur rent
dur ing decele ration
Ove r curren t
Check if there is any
betw een t he U, V, W and motor
short c irc uits and
grounding
Ye s
No
No
No
No No
No
Ye s
Ye s
Yes
Remove short c ircuit
or ground fault
Reduce the load or
increase the pow er
of AC motor drive
NoNo
Reduce torque
compensation
Reduce tor que
compensation
Suitable torque
compensation
No No
No
No
No
Ye s
Yes
Ye s
Yes
Yes
Maybe AC motor drive
has malfunction or error
due to noise. Please
contact DELTA.
Can acceleration
time be made longe r?
Can de c elerati o n
time be made l on ger?
Re du ce lo ad or in crease
the po w er of AC motor
drive
Check brake
method. Please
contact DELTA
Reduce load or increase
the power of AC motor
drive
Has l oad cha nged
suddenly?
Check if
acceleration time
is too short by
load inertia.
Check if
dec eleration time
is too short by
loa d inertia.
Increase accel/dec el
time
Che ck if load is too large