Danfoss VLT FC 280 Operating Manual page 115

VLT® Midi Drive FC 280
Operating Guide
Symptom Possible cause
Motor is running in Motor rotation limit
the wrong direction
Active reversing sig-
nal
Wrong motor phase
connection
Motor is not reaching Frequency limits are
maximum speed set incorrectly
Reference input sig-
nal not scaled cor-
rectly
Motor speed is unsta- Possible incorrect
ble parameter settings
Motor runs roughly Possible overmag-
netization
Motor does not brake Possible incorrect
settings in the
brake parameters.
Possible too short
ramp-down times.
Open power fuses or Phase-to-phase
circuit breaker trip short
Motor overload
Loose connections
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Test
• Is the reference signal local, remote, or
bus reference?
• Is preset reference active?
• Is terminal connection correct?
• Is the scaling of terminals correct?
• Is the reference signal available?
Check that parameter 4-10 Motor Speed Di-
rection is programmed correctly.
Check if a reversing command is program-
med for the terminal in parameter group
5-1* Digital inputs.
Change parameter 1-06 Clockwise Direction.
Check output limits in parameter 4-14 Motor
Speed High Limit [Hz] and parameter 4-19
Max Output Frequency.
Check reference input signal scaling in pa-
rameter group 6-** Analog I/O mode and pa-
rameter group 3-1* References.
Check the settings of all motor parameters,
including all motor compensation settings.
For closed-loop operation, check PID set-
tings.
Check for incorrect motor settings in all mo-
tor parameters.
Check brake parameters. Check ramp time
settings.
Motor or panel has a short phase-to-phase.
Check motor and panel phase for shorts.
Motor is overloaded for the application.
Perform pre-start-up check for loose con-
nections.
Maintenance, Diagnostics, and
Troubleshooting
Solution
correct wiring. Check scaling of
terminals. Check reference signal.
Program correct settings.
Deactivate reversing signal.
–
Program correct limits.
Program correct settings.
Check settings in parameter group
6-** Analog I/O mode.
Check motor settings in parame-
ter groups 1-2* Motor data, 1-3*
Adv motor data, and 1-5* Load in-
dep. setting.
Check parameter groups 2-0* DC
brake and 3-0* Reference limits.
Eliminate any shorts detected.
Perform the start-up test and veri-
fy that motor current is within
specifications. If motor current is
exceeding nameplate full load
current, the motor may run only
with reduced load. Review the
specifications for the application.
Tighten loose connections.
AQ381425076031en-000101 / 130R1223 | 115