Delta VFD-B User Manual

Revision July 2008, BE16, SW V4.08 & V5.00 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 de cele ration
Ove r curren t
Check if there is any
betw een t he U, V, W and motor
sh ort 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 t he power
of AC motor drive
NoNo
Reduce torque
compen sation
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 dec elerati o n
time be made l o nger?
Reduce lo ad or in crease
the power of AC motor
drive
Check brake
method. Please
contact D ELTA
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.
Incre ase accel/decel
time
Check if load is too large

Delta VFD-B Specifications

General

Series	VFD-B
Power Range	0.4kW to 15kW
Control Method	V/F Control, Sensorless Vector Control
Overload Capacity	150% for 60 seconds
Braking Unit	Built-in
Communication	RS-485
Protection Features	Over-voltage, Over-current, Overheat, Under-voltage, Ground fault, Short circuit