Table of Contents
Advertisement
·aT--GENERATOR mQUBLESHOOTING
MEASUBIIIG RESIDUAL VOLTAGI;
ItO-LOAD VOLTAGE
'The amount
of
no-load voltage produced
by
the generator
can
be an indicator
of
where in the generator the problem/fault
may lie.
Residual Voltage 18-22 Volts
This voltage is the AC voltage produced by the generator from
magnetism in the exciter stator field. This voltage is measured
between the AC Neutral and Hot leg(s) with no-load on the
generator running
at
60 hertz.
The presence of residual voltage is an indication that the
following generator components are OK.
Exciter Rotor B-1
a,
b, &
c
and B-2
Rotating Field
8-3
Main Stator c-1 and c-2
Compound iranstonner 0-1 and D-2
The fault lies in one or more of the following
components in the exciter circuit.
Exciter Stator A-1 [and A-2 if applicable]
Bridge Rectifier G
~elector
Switch
·[If
applicable]
Main Stator Auxiliary Windings C-3
Compound Transfonner Auxiliary Winding
D-3
12VOLT~ION
Twelve (12) volt DC excitation applied to the exciter stator
windings should cause the generator to
produce
between
140-150 voltsAC measured between the Une and Neutral.
(Normal Excitation 8-9 volts DC no load)
. STARTER MOlOR
Correct voltage produced with 12 volts excitation
in<licates
the fault is in one or more of the above listed components
G, C-3 or D-3.
If
the generator does not produce the correct voltage [140-
lSOV with excitation, then also include the rotor components
as possible faults. The Absence of any voltage from the
generator indicates a fault with the main stator windings C-1
and
c-z
and/or the compound transformer windings o-1· and
D-2 or possibly a shorted thermister. ·
Apply 12 volt DC excitation to the exciter stator windings
as illustrated. A fault in the main stator and/or compound
transformer windings such as a short will cause the generator
engine
to
load down and the shorted windings to eventually
produce smoke as
the
excitation is continued.
Voltage output greater than residual and·less
than
rated output
35-100 volts
indicates
a fault
in
the exciter rotor/field B-1, B-2
or B-3 .. Excitation of the generator should produce a
partial
rise in voltage output and, when removed, the voltage will
return to the original low ouput.
BRIDGE RECTIRER WIRING
The illustration
below shows the color coded wires
at
the
two
AC terminals and the color coded wires
at
the (
+)
and (-) DC
tenninalsi
Note: When removing or reinstalling connections, maintain
correct jx>la:rity connection on the (
+)
and (-)
DC terminals.
EXC.I1JJII(JTHE GENERATOR
WfrH
12
VOLTS.
ll~~'lilliz:=::::;::::.
DC(+)
to
LED
and
DC(-)
to giOund.
.
Keeping~·
EXciriiR CIRCUIT
pofariiy
Conect.
FRAME
(.W:JWESIERBEICE
Engines
&
Generators
41
Advertisement
Table of Contents
Troubleshooting
