Delta Electronics VFD-G manual Troubleshooting, Over Current OC, o cd

Chapter 5 Troubleshooting

5.1 Over Current (OC)

ocA

Ov er-curre nt

dur ing ac celeratio n

o cd

Over- c urrent during decele ration

O C

Ove r curren t

Remove short c ircuit or groun d fault

Yes	Check if there is any short c irc uits and
	groun ding between t he U, V, W and motor

			No	No	No
	Reduce the load or	Yes
	increase the power			Check if load is too large
	of AC motor drive		No	No	No
N o Reduce torque
		No Suitable torque
	compen sation	compensation
	Yes		Ye s

Red uce tor que
com pensa tion	Check if		Check if
No		No
	acceleration time		dec eleration time
	is too short by		is too short by
	load inertia.		loa d inertia.
Maybe AC motor dri ve	Ye s		Yes
has malfunction or error
due to noise. Pleas e			No	Has l oad cha nged
contact DELTA.
				suddenly?
				Ye s

Yes Can ac celerati on		Yes	Can dec elerati on
	time be made longer?		time be made l onger?
	No		No
Inc re ase ac cel/dec el				Reduce load or increase
time				the power of AC motor
				driv e
	Reduce lo ad or in crease		Check brake
	the power of AC motor		me thod. P lease
	dri ve		co ntact D ELTA

Revision July 2008, EG03, SW V1.06 5-1