Chapter 7 Troubleshooting; Over Current (Oc) - Delta VFD-BW Series User Manual

7.1 Over Current (OC)

Remove s hor t cir cuit
or ground fault
Reduc e the load or
incr eas e the power
of AC motor dr ive
Can torque
N o
compensation
be r educ ed?
Yes
R educ e torque
compensation
Maybe AC motor drive
has malfunc ti on or error
due to nois e. Please
contact DELTA.
Increase accel/decel
time
Revision May 2009, BWE0, SW V1.05
ocA
Ov er-c urrent
during acceleration
Yes
Yes
No
Is tor que
No
compensation
suitable?
Yes
Check if
No
acceler ati on time
is too short by
load iner ti a.
Yes
Yes
Can acc el er ation
time be made longer?
No
Reduc e load or inc rease
the pow er of AC motor
driv e

Chapter 7 Troubleshooting

ocd
Ov er-c urrent
during dec eleration
Check if there i s any
grounding between the U, V, W and motor
No
No
Check if load i s too lar ge
Check if
No
deceleration time
is too short by
load iner ti a.
Yes
C an deceleration
time be made longer?
C heck brake
method. Please
contact DELTA
OC
Ov er c urrent
short circ uits and
N o
Yes
Has l oad changed
No
suddenly?
No
R educ e load or inc rease
the power of AC motor
driv e
N o
No
Yes
7-1