MULTIQUIP DCA Series Service And Troubleshooting Manual page 87

Set Voltage Selector
With unit OFF, inspect
Switch or Bus Bars to
for loose damage or
240 Volts Three Phase
burnt wiring
Check all AVR plug
connections
Test Open
Delta Winding.
Disconnect 6 pin connector
fr om CN1 receptacle on
PASS
Measure resistance at pins
AB, CD, DA and BC on CN5 plug
Reference
for correct
resistance
Replace or refurbish main
stator (armature)
FAIL
Replace exciter field
and retest unit
With rectifier
PASS
disconnected
test main
field
FAIL
Replace or refurbish rotor
GENERATOR SERVICE AND TROUBLESHOOTING MANUAL — REV. #0 (08/29/23) — PAGE 87
TROUBLESHOOTING FLOWCHARTS
NO VOLTAGE
PASS
Check AVR fuse
FAIL
Replace fuse
AV R.
PASS
Table 6
FAIL
N o V o ltage rise o r very lit
indicate a insu lat ion rea b kd ow
fie d l when ba tte ry vo l t age s ap i
off a d e o m n p rf r ins lat u i on est on e citer t
R efer t o in sula t ion t est for et d
Disconnect
stator leads from
PASS
voltage selector switch
Refer to stator
test section
FAIL
Replace or refurbish stator
Verify no voltage
output. Start unit and
run at 1800 RPM. Verify
output voltage at top of circuit
breaker with multimeter.
Phase to Phase and
Phase to Neutral.
FAIL
PASS
Check rheostat (VR)
circuit
FAIL
Replace Rheostat
and retest
Manual
Excitation Field
Test
Disconnect 6 pin connector
fr om CN1 receptacle on AV R.
Connect 12 VDC battery to pins
J and K on CN5 plug
Reference Table 7
for correct
voltage
FAIL
Test Rotating
Rectifier. Reference
t e l r ise co u ld
Rotating Rectifier
n i n t e exci e h t r
test section.
p e li d. Sh ut u n i t
x field.
FAIL
a s. il
Replace rotating rectifier.
Inspect and troubleshoot
PASS
voltmeter on control
panel/digital controller
Test exciter
field.
Disconnect 6 pin connector
from CN1 receptacle on AVR.
Measure resistance at pins
J and K on CN5 plug.
Reference Table 6
for correct
resistance
FAIL
Repair wiring or
replace Exciter Field
If AC output voltage
meets values as
PASS
referenced in Table 7
Indicates faulty AVR,
Replace AVR and
retest unit.
PASS
With Rotating
Rectifier disconnected
test Exciter
Armature
PASS
Replace or
refurbish rotor
PASS
FAIL