Danfoss VLT AQUA FC 202 Operating Instructions Manual page 44

Maintenance, Diagnostics an...
Symptom
Motor not
running
7 7
Motor running
in wrong
direction
Motor is not
reaching
maximum
speed
Motor speed
unstable
Motor runs
rough
Motor will not
brake
Open power
fuses or circuit
breaker trip
42
Possible cause
Service switch is open or
missing motor connection
No mains power with 24 V DC
option card
LCP stop
Missing start signal (Standby)
Motor coast signal active
(Coasting)
Wrong reference signal source
Motor rotation limit
Active reversing signal
Wrong motor phase connection
Frequency limits are set
incorrectly
Reference input signal is not
scaled correctly
Possible incorrect parameter
settings
Possible over-magnetisation
Possible incorrect settings in
the brake parameters. Possible
too short ramp-down times
Phase-to-phase short circuit
Motor overload
Loose connections
Danfoss A/S © Rev. 05/2014 All rights reserved.
Operating Instructions
Test
Check if the motor is connected and the
connection is not interrupted (by a service
switch or other device).
If the display is functioning but no output,
check that mains power is applied to the
frequency converter.
Check if [Off] has been pressed.
Check 5-10 Terminal 18 Digital Input for
correct setting for terminal 18 (use default
setting).
Check 5-12 Coast inv. for correct setting for
terminal 27 (use default setting).
Check reference signal: Local, remote or
bus reference? Preset reference active?
Terminal connection correct? Scaling of
terminals correct? Reference signal
available?
Check that 4-10 Motor Speed Direction is
programmed correctly.
Check if a reversing command is
programmed for the terminal in parameter
group 5-1* Digital inputs.
Check the output limits in 4-13 Motor Speed
High Limit [RPM], 4-14 Motor Speed High
Limit [Hz] and 4-19 Max Output Frequency.
Check the reference input signal scaling in
6-0* Analog I/O Mode and parameter group
3-1* References. Check the reference limits
in parameter group 3-0* Reference Limit.
Check the settings of all motor parameters,
including all motor compensation settings.
For closed-loop operation, check the PID
settings.
Check for incorrect motor settings in all
motor parameters.
Check the brake parameters. Check the
ramp-time settings.
The motor or panel has a short phase-to-
phase. Check the motor and panel phase
for short circuits.
Motor is overloaded for the application.
Perform a pre-startup check for loose
connections.
Solution
Connect the motor and check the service
switch.
Apply mains power to run the unit.
Press [Auto On] or [Hand On] (depending
on operation mode) to run the motor.
Apply a valid start signal to start the
motor.
Apply 24 V on terminal 27 or program this
terminal to No operation.
Programme the correct settings. Check
3-13 Reference Site. Set preset reference
active in parameter group 3-1* References.
Check for correct wiring. Check scaling of
terminals. Check reference signal.
Programme the correct settings.
Deactivate reversing signal.
See chapter 5.5 Checking Motor Rotation.
Programme the correct limits.
Programme the correct settings.
Check the settings in parameter group 1-6*
Load Depen. Setting. For closed-loop
operation, check the settings in parameter
group 20-0* Feedback.
Check the 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 short circuits detected.
Perform a startup test and verify the motor
current is within the specifications. If the
motor current exceeds the nameplate full
load current, the motor may run only with
reduced load. Review the specifications for
the application.
Tighten any loose connections.
MG20MB02