MULTIQUIP DCA Series - No Voltage - Residual Voltage Flowchart

PAGE 86 — GENERATOR SERVICE AND TROUBLESHOOTING MANUAL — REV. #0 (08/29/23)
TROUBLESHOOTING FLOWCHARTS
N vo ro rise o t e coltage very ise ldr lit l u
insu ion rea n indicate a ow t e Exci elat b kd n h ti r
nFie d ry vo li d. Sh il iwhen ba age s ap utte t p e ut tl
p rf t Exoff a d e o m on est on citer n r uins lat Field.i
ion dR o sula est a s.efer t t for etin t il
Voltage rise is low, replace
AVR and test Rotating Rectifier.
Replace Exciter Field
and retest unit
Replace or refurbish Main
Stator (Armature)
PASS
Set Voltage Selector
Switch or Bus Bars to
240 Volts Three Phase
FAIL
Inspect and troubleshoot
voltmeter on control
panel/digital controller
With unit OFF, inspect
for loose damage or
burnt wiring
Check all AVR plug
connections
Check AVR fuse
Check rheostat (VR)
circuit
FAIL
Replace Fuse
PASS
FAIL
Replace Rheostat
and retest
PASS
Disconnect 6 pin connector
from CN1 receptacle on AVR.
Measure resistance at pins
Test exciter
field.
Reference Table 6
J and K on CN5 plug.
for correct
resistance
FAIL
Repair wiring or
replace Exciter Field
PASS
PASS
Test Open
Delta Winding.
Disconnect 6 pin connector
fr AVom CN1 receptacle on R.
Measure resistance at pins
AB, CD, DA and BC on CN5 plug
Reference Table 6
for correct
resistance
FAIL
Manual
Excitation Field
Test
Disconnect 6 pin connector
fr AVom CN1 receptacle on R.
Connect 12 VDC battery to pins
J and K on CN5 plug
Reference Table 7
for correct
voltage
PASS PASS
If AC output voltage
meets values as
referenced in Table 7
Indicates faulty AVR,
Replace AVR and
retest unit.
FAIL
FAIL
FAIL
NO VOLTAGE - RESIDUAL VOLTAGE ONLY
Verify Low
Voltage Output
Neutral
Start unit and run at
1800 RPM. Verify output voltage
at top of circuit breaker with
multimeter. Phase to Phase
and Phase to
Resistance tolerance
is ± 2 ohms.