TROUBLESHOOTING
TESTING AND ADJUSTING
POSSIBLE CAUSES
VERIFICATION PROCEDURE
1. Voltmeter has a Defect
Check voltage with a meter with known accuracy. Check fuses and
connections in the control panel voltmeter circuit. NOTE: The
magnetic field caused by current flow in power cables that are
close to the voltmeter can cause the voltmeter to be wrong. If the
voltmeter is fastened to a part of the control panel that can be
moved or opened, open or move it and read the meter in this
position. If the meter indication is correct after being moved,
change the position of the power cables or prevent the magnetic
field from causing an error in the meter indication.
2. Open (Tripped) Thermal
Set the thermal protector (TP) again. The thermal protector opens
Protector (TP)
(trips) when the load is too high or when the load is not in
balance. Make the necessary corrections to the load.
3. Open Fuse (F1)
Remove the fuse and check it with an ohmmeter or continuity
circuit tester, similar to 8S4627.
NOTICE: An open fuse is normally caused by a high voltage
condition. NOTE: Fuse (F1) Is the type that opens very rapidly
and gives protection to the semiconductors used in the control
circuits. Do not use a replacement of any other type, or of
a higher rated amperage.
4. Engine Low Idle RPM Too Low
Voltage does not get higher at factory set low idle of 1200 to
1250 rpm. If the outside temperature is low, the controlled
rectifier (CR9) will be more difficult to "turn on" by residual
voltage. An increase of the engine idle rpm of approximately 100
to 150 rpm must show an increase of voltage.
5. Defect in Rotating Rectifiers
WARNING
(CR1 thru CR6); Surge
Suppression Diodes (CR7, 8);
Do what is necessary to keep the engine starting motor from being
activated during this test.
Exciter Armature (L4)
WARNING
or Exciter Field (L3)
(Use this method when 110V
Be extra careful when using this procedure. The 110 V AC wires
must be kept insulated from the generator frame.
AC is available.)
Disconnect its wires (F1) and (F2) from terminals (F1) and (F2)
Check continuity through wires (F1) and (F2). Typical resistance
is 2 to 3 ohms.
Now connect the 110V AC wires to wires (F1) and (F2). The
110V AC activates the exciter field (L3).
Connect a DC voltmeter between the positive heat sink (E1) and
the negative heat sink (E2).
Using a bar or engine turning tools, slowly turn the engine flywheel
approximately 90. At the same time make a note of the measurement on
the DC voltmeter. If all the parts are good, the voltage measurement will
increase and decrease evenly and the minimum voltage will be at least
80% of the maximum voltage. If the minimum voltage is less than 80%
of the maximum or less than 2 volts, check the parts one at a time
according to the Troubleshooting Procedure.
6. Exciter Field (L3) is Open
Disconnect wire (F1) from terminal (F1). Check the continuity of
exciter field ( L3) from wire(F1) to terminal (F2). Typical resistance
values are found on EDS sheets 70.0.1 or on the current TIF.
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