Delta Electronics VFD-VL manual Low Voltage Lv, Suitable power

Chapter 5 Troubleshooting

5.4 Low Voltage (Lv)

	Low voltage
						Yes
Power cut, including momentary
power loss								Restart after reset
		No
Check if there is any malfunction			Yes
							Change defective component
component or disconnection in							and check connection
power supply circuit
		No
Check if voltage is				No				Change power supply
within specification								system for requirement
		Yes
Check if there is heavy load					Yes Using the different power
with high start current in the							supply for this drive and
same power system							heavy load system
		No							No
Check if Lv occurs when			Yes
								Suitable power
breaker and magnetic								transformer capacity
contactor is ON

No

Check if voltage between +1/+2 No and - is greater than Pr.06-00

Yes

Control circuit has malfunction or misoperation due to noise. Please contact DELTA.

Yes

Maybe AC motor drive has malfunction. Please contact DELTA.

Revision Nov. 2008, VLE1, SW V1.03 5-3