Delta VFD-B Series User Manual

Chapter 7 Troubleshooting |VFD-B-P Series
Revision April 2009, SW V1.00 7-3
7.4 Low Voltage (Lv)
Low voltage
Is input power correct? Or power cut,
including momentary power loss
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
Restart after reset
Check if there is any malfunction
component in
power supply circuit
or disconnection
Change defective component
and check connection
Check if voltage is
within specification
Make necessary corrections,
such as change power supply
system for requirement
Check if there is heavy load
with high start current in the
same power system
Check if Lv occurs when
breaker and magnetic
contactor is ON
Suitable
transformer
power
capacity
Check if voltage between +1/+2
and - is greater than 400VDC
Maybe AC motor drive has malfunction.
Please contact DELTA.
Control circuit has malfunction or
misoperation due to noise. Please
contact DELTA.

Delta VFD-B Series Specifications

General

Series	VFD-B
Cooling Method	Fan cooling
Overload Capacity	150% for 60 seconds
Braking Unit	Built-in
Control Mode	V/F control, Sensorless Vector Control
Communication	RS-485
Protection Features	Overvoltage, Undervoltage, Overcurrent, Overload, Overtemperature, Short Circuit
Operating Temperature	-10°C to +50°C
Storage Temperature	-20°C to +60°C
Humidity	90% RH (non-condensing)
Altitude	1000m (Derating required above 1000m)