Westerbeke 8.0KW-60Hz Service Manual page 77

('
BT GENERATOR TflO.UBLESHOOTING/SINGLE PHASE
1
CURReNT ReCTIFieRS
ARe CONFIGUReD SLIGHTLY
DIFFeRENTLYBIlrTEST.
POINTS ARE THE SAME.
E.
j
A.C.
'Thrminal
Bo~rd
.
G.
Bridg~ Rectifi~
E
Selector Switch
H. ~Optlona1
AVR
The model code number is found stamped in the generator
housing on a flat surface above the rear generator carrier
. 3 .
bearing.
4
TESTING THE
BRIDGE RECTiFIER .
4. Leaving the negative (-) ohmmeter lead on point #4,
touch point #5 with the positive (+) lead. No deflection of
the needle should occur.
S. Place the positive (+) lead of the ohimneter on point #1
and the negative (.) lead on point #3. The ohnuneter
should not register any deflection of the needle (no
deflection indicates infinite resistance). Reverse these
connections lind the ohnuneter should again register no
deflection.
If
the rectifier fails any of the previous tests (I - 4) it is
defective and should be replaced.
NOTE:
Different style/model meters may produce opposite
results from the above testi.
Component Resistance Values·
A. Exciter Stator
B. Excitor RotorlField
A-I &A-2 11.5 ohm B-1 1.05 ohm,
A-I 49.4 ohm
A-2 12.9 ohm
B-3 8.9 ohm
C. Main Stator
C-I 0.089 ohm
C-2 0.089 ohm
Auxiliary Windings
C-3 0.85 ohm
D. Compound Transformer
D-I 0.007 ohm
r-------------------l
A
I B
I
,
,
- +:
'00:
II . : *
4
I
I
b
I
I 1 2' 3
I
~ _________________ J
D-2 0.007 ohm
Auxiliary Wmdings
D-3 5.02ohm
C
I
!
,
! !
D
. NOTE:
These two model BT generators are used on models
rated lower than the capabilities of the generator. However,
the generator is rated according to the capabilities of the
drive engine since horsepower produces kilowatts.
. COMPONENT RESISTANCE CHECKS
Exciter Stator Windings
1. Windings A-1 and A·2
Resistance readings for exciter windings A-I and A-2
with the selector switch in the COMP position are taken
between the positive (+) and negative (-) leads lifted off
the bridge ·rectifier (0). Neither of these two leads should
have the continuity to the generator case/ground.
2. WmdingA·1
Resistance readings for exciter windings A-I with the
selector switch in the ELEC position is taken between
the
yellow wire and the black at the AY.R. plug (0).
3. Wmding A·2
Resistance readings for exciter winding A·2 with the
selector switch in the ELEC position is taken between the
green wire lifted off the negative (-) tenninal of the bridge
rectifier (0) and the red wires lifted off the positive (+)
tenninal of the bridge rectifier (0).
NOTE:
Tlie white striped wiring on earlier model generators
has been changed to solid colors on current generators, the
colors, however, .remain
the
same.
E
.,
.,
3
V1
.7
.,
.s
W2
'7
.,
RED
GREEN
BLUE/WHII'E
(fO PIN 18TERM.
-
BLUE/WHITE
(TO
HEFI17NOLTS BAR)
\ 'la'
I
\I\.ACK
.. ' " wu.c:m
BUICK
RED/WHITE
(l'O HI!RTlNOLTS eAR)
BLACK/WHITE
(TO BRIDGE RECTIFIER)
+
AVR
PLUG
BLACK/WHITE
(TO SELECTOR SWITCH)
YELLOW IWHITE
(l'O SELECTOR SWITCH)
L. ~fErro.r----------~~~j_~;;;:;;~~~;;= ·50c~
~
WESTERBEKE
BT GENERATOR
INTERNAL WIRING
SCHEMATIC
(W/OPTIONAL AVR) ..
Engines & Generators
71