WEG MW500 User Manual - page 38

32 | MW500

Troubleshooting and Maintenance

- English -

6 TROUBLESHOOTING AND MAINTENANCE

6.1 FAULT AND ALARMS

NOTE!

Refer to the quick reference and to the programming manual of the 

MW500 for further information about each fault or alarm.

6.2 SOLUTIONS FOR THE MOST FREQUENT PROBLEMS

Table 6.1: Solutions for the most frequent problems

Problem

Point to be verified

Corrective Action

Motor will not 

start

Incorrect wiring

1. Check all the power and command connections.

Analog reference 

(if used)

1. Check if the external signal is properly connected.

2. Check the status of the control potentiometer (if used).

Wrong settings

1. Check if the parameter values are correct for the application.

Fault

1. Check if the drive is disabled due to a fault condition.

Motor stall

1. Decrease the motor overload.

2. Increase P0136, P0137 (V/f).

Motor speed 

oscillates

Loose connections

1. Stop the drive, turn off the power supply and tighten all the 

connections.

2. Check all the internal connections of the drive.

Defective speed 

reference 

potentiometer

1. Replace the potentiometer.

Oscillation of the 

external analog 

reference

1. Identify the cause of the oscillation. If the cause is electrical 

noise, use shielded cables or separate them from the power 

or command wiring.

2. Interconnect the GND of the analog reference to the grounding 

connection of the drive.

Too high or too 

low motor speed

Incorrect settings

(reference limits)

1. Check whether the content of P0133 (minimum speed) and 

P0134 (maximum speed) are properly set for the used motor 

and application.

Control signal of the 

analog reference

(if used)

1. Check the level of the reference control signal.

2. Check the setting (gain and offset) of parameters P0232 to 

P0240.

Motor nameplate

1. Check whether the motor used matches the application.

Display off

HMIR connections  

1. Check the connections of the drive external HMIR.

Power supply voltage   1. Rated values must be within the limits specified below: 

    380-480 V power supply: - Min: 323 V - Max: 528 V.

Main supply fuse open 1. Replace the fuses.