Eurotherm Drives 590 DRV Digital, Product Manual, Page: 61 / 318

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5
590 DRV Digital DC Drive Product Manual
Chapter 5 Troubleshooting
Figure 5.7 - Alarm Messages (Continued)
DISPLAY MESSAGE MEANING POSSIBLE CAUSE CORRECTIVE ACTION
*** ALARM ***
FIELD OVER I
Field over current. Field current
exceeds 120% (alarm only operates
if field is in Current Control Mode).
Drive field current miscalibrated. Repeat field supply set up procedure.
External field supply connected
incorrectly.
Check the external field supply phasing
(see Chapter 3).
*** ALARM ***
HEATSINK TRIP
Heatsink thermostat open; drive
overheated.
Fan failure or obstruction. Check drive fan rotating (when fans
fitted).
Fan fuse blown. Check FS1.
Plug PLN not fully inserted. Check heatsink plug PLN fully inserted in
power supply pcb.
Inadequate enclosure ventilation. Check enclosure fan and filter. Check
location of drive meets manual
installation requirements.
Extreme ambient temperature. Measure enclosure internal temperature.
Fit ventilation fans or air conditioning if
ambient exceeds drive specification [see
VENTILAION & COOLING
REQUIREMENTS in Chapter 3].
Drive miscalibrated. Check drive calibration. Mis-calibration
can cause overheating.
INITIALIZING
IA FBK CAL FAIL
Armature current feedback
calibration fail during the power-up
self test.
Armature current feedback current
transformers miswired.
Check ACCT wiring and PLK jumpers on
the power supply board.
Control board defective. Replace control board.
*** ALARM ***
MISSING PULSE
Missing armature current pulse.
Irregular armature current waveform
detected. (Armature current must be
1.5 times the discontinuous current
level and missing pulse must be
present for 60 seconds for alarm to
operate).
NOTE. Ripple from the speed loop
can cause unstable current.
Drive not AUTOTUNEd (Unstable
current loop).
Perform the AUTOTUNE procedure.
SCR gate connection loose. Check SCR gate connections from the
trigger board to the SCR gate leads.
SCR defective. Check SCRs with an ohmmeter: See SCR
Troubleshooting in this chapter.
SCR firing pcb defective. Replace the pcb.
Motor has opened or shorted coil. Check the motor with an ohmmeter and
megger for insulation and continuity.
Coupling between motor and
feedback device slipping
Stop drive and isolate power. Check
coupling tightness.
Feedback device noisy or defective. Replace tachometer generator if noise is
present while observing feedback with an
oscilloscope.
Bottom two LEDs on the 5701 or 5901
Microtach receiver board are out.
Weak feedback signal intensity; check
connections, fiber optic wire integrity,
and transmission distances.
Speed loop gain too high. Retune drive speed loop.