Kohler 11.5EFOZ, Руководство по обслуживанию

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TP-6071 3/00 33 Section 7 Generator Troubleshooting
7. Rotate the volts/Hz potentiometer clockwise until
the voltage level as measured on the voltmeter
begins to drop. When the regulator is set to these
specifications
the generator will attempt to
maintain normal output until the engine speed
drops below the frequency set in step 6.
8. Readjust the engine speed to 63 Hz or 52 Hz.
9. Readjust the voltage adjustment potentiometer
until the desired output is achieved.
10. Readjust the stability potentiometer until the test
light flickers minimally.
11. Place the generator set controller start/stop switch
in the STOP position.
7.7 Exciter Field
Direct current from the battery magnetizes the exciter
field.
When the exciter armature rotates within the
magnetized exciter field windings, an electrical current
develops within the exciter armature. Test the exciter
field according to the following procedure.
Exciter Field Test Procedure:
1. Place the start/stop switch in the STOP position.
2. Disconnect the generator set engine starting
battery, negative (--) lead first.
3. Disconnect the P6 connector (F1/F2 leads).
4. Check the exciter field resistance by connecting an
ohmmeter across exciter field F1 and F2 leads.
See Figure 7-7. See Section 1, Specifications for
the resistance reading of a cold exciter field. A low
reading indicates an internal short and a high
reading indicates an open winding.
Repair or
replace the exciter field if the ohmmeter readings
indicate a inoperative exciter field (refer to
Section 9 for removal). If the resistance test is
inconclusive, perform a megohmmeter test on the
exciter field as described in the next step.
1
3
4
F1 F2
P6
TP-5983-7
2
1. Voltage regulator
2. Ohmmeter
3. Exciter field
4. Exciter armature
Figure 7-7 Exciter Field Resistance Test
5. Check the exciter field for a short-to-ground
condition. Use a megohmmeter to apply 500-volts
DC to the F1 or F2 lead and the exciter field frame.
See
Figure 7-8. Follow the megohmmeter
manufacturer’s instructions for using the
megohmmeter. A reading of approximately
1.5 MOhms and higher indicates the field winding
is functional. A reading of less than approximately
1.5 MOhms indicates deterioration of the winding
insulation and possible current flow to ground; If
so, replace the exciter field.
1
3
F1 F2
P6
4
5
TP-5983-7
2
1. Voltage regulator
2. Megohmmeter
3. Frame connection
4. Exciter armature
5. Exciter field
Figure 7-8 Megohmmeter Connections on the
Exciter Field