Danfoss VLT AutomationDrive FC 302 Operating Instructions Manual page 61

Maintenance, Diagnostics an...
Symptom Possible cause
Motor is not Frequency limits set wrong.
reaching
maximum
speed Reference input signal not
scaled correctly.
Motor speed Possible incorrect parameter
unstable settings.
Motor runs
Possible overmagnetisation.
rough
Possible incorrect settings in
Motor does
the brake parameters. Possible
not brake
too short ramp down times.
Phase-to-phase short.
Open power
fuses or
Motor overload.
circuit
breaker trip
Loose connections.
Problem with mains power (see
Alarm 4 Mains phase loss
Mains current
description).
imbalance
greater than
Problem with the frequency
3%
converter.
Problem with motor or motor
Motor current
wiring.
imbalance
greater than
Problem with frequency
3%
converter.
Frequency
converter Motor data are entered
acceleration incorrectly.
problems
Frequency
converter Motor data are entered
deceleration incorrectly.
problems
Table 7.5 Troubleshooting
MG34U402
Operating Instructions
Test
Check output limits in parameter 4-13 Motor
Speed High Limit [RPM], parameter 4-14 Motor
Speed High Limit [Hz], and parameter 4-19 Max
Output Frequency
Check reference input signal scaling in
parameter group 6-0* Analog I/O mode and
parameter group 3-1* References.
Check the settings of all motor parameters,
including all motor compensation settings.
For closed loop operation, check PID settings.
Check for incorrect motor settings in all
motor parameters.
Check brake parameters. Check ramp time
settings.
Motor or panel has a short phase-to-phase.
Check motor and panel phases for shorts.
Motor is overloaded for the application.
Perform pre-start-up check for loose
connections.
Rotate input power leads into the 1 position:
A to B, B to C, C to A.
Rotate input power leads into the frequency
converter 1 position: A to B, B to C, C to A.
Rotate output motor leads 1 position: U to V,
V to W, W to U.
Rotate output motor leads 1 position: U to V,
V to W, W to U.
If warnings or alarms occur, see
chapter 7.5 List of Warnings and Alarms.
Check that motor data are entered correctly.
If warnings or alarms occur, see
chapter 7.5 List of Warnings and Alarms.
Check that motor data are entered correctly.
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Solution
Programme correct limits.
Programme correct settings.
Check settings in parameter group 1-6*
Load Depen. Setting. For closed loop
operation, check settings in parameter
group 20-0* Feedback.
Check motor settings in parameter groups
1-2* Motor data 1-3* Adv Motor Data, and
1-5* Load Indep. Setting.
Check parameter group 2-0* DC Brake and
3-0* Reference Limits.
Eliminate any shorts detected.
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.
Tighten loose connections.
If imbalanced leg follows the wire, it is a
power problem. Check the mains power
supply.
If the imbalanced leg stays on same input
terminal, it is a problem with the
frequency converter. Contact supplier.
If the imbalanced leg follows the wire, the
problem is in the motor or motor wiring.
Check motor and motor wiring.
If the imbalanced leg stays on same
output terminal, it is a problem with the
unit. Contact supplier.
Increase the ramp-up time in
parameter 3-41 Ramp 1 Ramp Up Time.
Increase current limit in
parameter 4-18 Current Limit. Increase
torque limit in parameter 4-16 Torque Limit
Motor Mode.
Increase the ramp-down time in
parameter 3-42 Ramp 1 Ramp Down Time.
Enable overvoltage control in
parameter 2-17 Over-voltage Control.
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