Symptom Possible Cause Test Solution
Motor is not
reaching
maximum
speed
Frequency limits set wrong.
Check output limits in 4-13 Motor Speed High
Limit [RPM], 4-14 Motor Speed High Limit [Hz],
and 4-19 Max Output Frequency
Program correct limits.
Reference input signal not
scaled correctly.
Check reference input signal scaling in
parameter group 6-0* Analog I/O mode and
parameter group 3-1* References.
Program correct settings.
Motor speed
unstable
Possible incorrect parameter
settings.
Check the settings of all motor parameters,
including all motor compensation settings.
For closed-loop operation, check PID settings.
Check settings in parameter group 1-6*
Load Depen. Setting. For closed-loop
operation, check settings in parameter
group 20-0* Feedback.
Motor runs
rough
Possible overmagnetization. Check for incorrect motor settings in all
motor parameters.
Check motor settings in parameter
groups 1-2* Motor data 1-3* Adv Motor
Data, and 1-5* Load Indep. Setting.
Motor does
not brake
Possible incorrect settings in
the brake parameters. Possible
too short ramp-down times.
Check brake parameters. Check ramp time
settings.
Check parameter group 2-0* DC Brake and
3-0* Reference Limits.
Open power
fuses or
circuit
breaker trip
Phase-to-phase short. Motor or panel has a short phase-to-phase.
Check motor and panel phases for shorts.
Eliminate any shorts detected.
Motor overload. Motor is overloaded for the application. Perform start-up test and verify that
motor current is within specifications. If
motor current is exceeding the nameplate
full load current, the motor may run only
with reduced load. Review the specifi-
cations for the application.
Loose connections. Perform pre-start-up check for loose
connections.
Tighten loose connections.
Line power
current
imbalance
greater than
3%
Problem with line power (see
Alarm 4 Mains phase loss
description).
Rotate input power leads into the 1 position:
A to B, B to C, C to A.
If imbalanced leg follows the wire, it is a
power problem. Check the line power
supply.
Problem with the adjustable
frequency drive.
Rotate input power leads into the adjustable
frequency drive one position: A to B, B to C,
C to A.
If imbalance leg stays on same input
terminal, it is a problem with the
adjustable frequency drive. Contact
supplier.
Motor current
imbalance
greater than
3%
Problem with motor or motor
wiring.
Rotate output motor leads one position: U to
V, V to W, W to U.
If imbalanced leg follows the wire, the
problem is in the motor or motor wiring.
Check motor and motor wiring.
Problem with adjustable
frequency drive.
Rotate output motor leads one position: U to
V, V to W, W to U.
If imbalance leg stays on same output
terminal, it is a problem with the unit.
Contact supplier.
Adjustable
frequency
drive
acceleration
problems
Motor data are entered
incorrectly.
If warnings or alarms occur, see
chapter 7.4 List of Warnings and Alarms
Check that motor data are entered correctly.
Increase the ramp-up time in 3-41 Ramp 1
Ramp-up Time. Increase current limit in
4-18 Current Limit. Increase torque limit in
4-16 Torque Limit Motor Mode.
Adjustable
frequency
drive
deceleration
problems
Motor data are entered
incorrectly.
If warnings or alarms occur, see
chapter 7.4 List of Warnings and Alarms
Check that motor data are entered correctly.
Increase the ramp-down time in
3-42 Ramp 1 Ramp-down Time. Enable
over-voltage control in 2-17 Over-voltage
Control.
Table 7.5 Troubleshooting
Maintenance, Diagnostics an...
Instruction Manual
MG33AP22 Danfoss A/S © Rev. 09/2014 All rights reserved. 51
7 7
To Next Page
Loading...
Need help?
General