MULTIQUIP DCA Series - Manual Excitation Winding Voltage Test

GENERATOR SERVICE AND TROUBLESHOOTING MANUAL — REV. #0 (08/29/23) — PAGE 39
MANUAL EXCITATION WINDING VOLTAGE TEST
MANUAL EXCITATION TEST (WINDING VOLTAGE)
1. With the engine OFF, place the voltage selector
switch (Figure 40A) in the 3-Phase, 240/139V position.
2. Unplug the 6-pin plug from the CN1 receptacle on the
AVR (Figure 40B).
3. Connect an SPST toggle switch (Figure 40C) between
the positive battery terminal and pin J on the CN5 plug.
4. Connect a wire from the negative battery terminal to
pin K on the 6-pin plug (Figure 40D).
5. Place toggle switch in the OFF (open) position, then
set engine speed switch to low postion (idle). Start the
engine and then place toggle switch in ON position
(closed).
6. Next, place engine speed switch in the high position
and run the engine at full rpm.
7. Place the selection dial on the multimeter to the AC
volts position (Figure 40E).
8. Connect the test leads of the multimeter across pins
A-B, C-D and D-A on the 6-pin plug as shown in
Figure 40F.
9. Verify that the voltage readings are within range as
referenced in Table 7, column F.
Figure 40. Manual Excitation Winding Voltage Test
3 PHASE
480/277
1 PHASE
240/120
3 PHASE
240/139
PRESS TO LOCK
SPST
TOGGLE
SWITCH
OFF
ON
EXAMPLE:
DCA-25SSIU4F
A
D
DISCONNECT CN5
PLUG FROM AVR
CN1 RECEPTACLE
2 1
A J C
DKB
3
CN1
CN2
CN3
CN4
2
C J A
B
K
D
1
3
YELLOW
WHITE
ORANGE
GRAY
BLUE
RED
6-PIN
PLUG
1
U
V
W
3-POLE
CIRCUIT
BREAKER
FAN
EXCITER
STATOR
MAIN
STATOR
MAIN FIELD
ROTOR
EXCITER
ARMATURE
RECEPTACLE
5
4
6
AVR
STATOR
FRAME
B
1
NOTES:
WIRE COLOR SHOWN IS FOR
A DCA-25SSIU4F GENERATOR.
ALL OTHER DCA GENERATORS
USE BLACK WIRES.
C
TURN
SELECTION
DIAL TO
POSITION
A ~ B = 72 VAC
EXCITATION WINDING
VOLTAGE @ 60 Hz
TEST CHART
CN5 PLUG REAR
VIEW WIRE SIDE
12V BATTERY
DANGER!
ELECTRIC SHOCK
(Live Terminals)
C ~ D = 72 VAC
D ~ A = 72 VAC
RANGE
MIN MAX
MULTIMETER
Auto0 600
OFF
Hz
C
A
mA
uA
F
V
Hz
V
mV
Hz %REL
HOLD/LIGHT
10 A
MAX
mAµA
COM
V
AC
E