Eurotherm Drives 590 DRV Digital, Product Manual, Page: 74 / 318

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590 DRV Digital DC Drive Product Manual
5
Chapter 5 Troubleshooting
Motor Checks
Several alarm messages are caused by problems with the motor. Most motor problems relate to insulation breakdown,
overtemperature and armature brush and commutation problems. Check the motor armature and field with a megger
to ensure that the motor winding insulation has not degraded and shorted one conductor to another or to ground.
Continuity checks require an ohmmeter for determining whether motor windings or leads have opened or shorted.
Continuity measurements should be less than one
W
. Insulation measurements should be greater than 10 M
W
.
NOTE. Armature resistance for motors less than 10 HP (7.5 KW) can measure up to 3 W .
Caution
Disconnect the motor leads from the drive before using a megger to check for motor ground faults.
Also check the motor commutator for flashover. Clean the commutator and motor brushes if worn or dirty. If the
motor is fitted with a blower, change or clean the blower filter regularly.
CONFIGURATION ERRORS AND GENERAL TROUBLESHOOTING
Many of the problems are associated with configuration errors. You can avoid them by carefully following the
configuration guidelines in Appendix C and Appendix D.
Use the software block diagram (located on the inside cover) to track signals when troubleshooting software problems.
Refer to the drawing at the end of Appendix D for a more detailed software block diagram. Trace the signal from its
start and monitor it at each point along the path using the MMI display. That should uncover mis-tagged parameters,
unwanted offsets, and mis-calibrated parameters.
The software package ConfigEd Lite displays drive configurations in graphical form on a personal computer (PC)
monitor. You can tack down configuration errors easily by referring to this graphical representation of your configu-
ration. Use the ConfigEd Lite
PRINT function to obtain a hard copy (refer to the ConfigEd Lite manual RG352747).
Caution
Because you can make configuration changes through the drive MMI, the configuration downloaded in
your 590 DRV may not match the ConfigEd Lite file on your PC. Be certain to update your drive
configuration data files with the ConfigEd Lite
UPDATE
command before printing out your
configuration.
Common Performance Problems
Parameter Toggles Between Two Conditions
This problem occurs when two parameters write to a third parameter. The two parameters overwrite each other and
fight for control of the problem parameter.
No SPEED DEMAND
If all the analog signals are connected to the proper terminals and have the correct sign, I DMD. ISOLATE may be set
incorrectly. Monitor terminal C8; if it is OFF, at 0 VDC, terminal C8 may have been tagged for a nonstandard
function. Monitor parameter SETUP PARAMETERS::CURRENT LOOP::I DMD. ISOLATE. It should be DIS-
ABLED for speed control. If I DMD. ISOLATE is ENABLED, only a signal at terminal A3, ANALOG I/P 2, will
create a current demand needed to turn the motor.