Stator - Kohler 8.5RES Service Manual

5.3 Stator

The stator contains a series of coils of wire laid in a
laminated steel frame. The stator leads supply AC
voltage to the load and voltage regulator. Before testing
the stator, inspect it for heat discoloration and visible
damage to housing lead wires, exposed coil windings,
and exposed areas of frame laminations. Be sure the
stator is securely fastened to the stator housing.
Note: Disconnect all stator leads before performing all
stator tests.
WARNING
Hazardous voltage.
Can cause severe injury or death.
Operate the generator set only when
all guards and electrical enclosures
are in place.
High voltage test. Hazardous voltage can cause severe
injury or death. Follow the instructions of the test equipment
manufacturer when performing high-voltage tests on the rotor
or stator. An improper test procedure can damage equipment
or lead to generator set failure.
Short circuits. Hazardous voltage/current can cause
severe injury or death. Short circuits can cause bodily injury
and/or equipment damage.
connections with tools or jewelry while making adjustments or
repairs. Remove all jewelry before servicing the equipment.
Stator Continuity and Resistance Tests
1. Place the generator set master switch in the OFF
position.
2. Disconnect power to the battery charger.
3. Disconnect the generator set engine starting
battery, negative (--) lead first.
4. Disconnect all stator leads before performing all
stator tests.
5. To check for stator continuity, set the ohmmeter on
R x 1 scale. First set the ohmmeter zero by holding
the red and black meter leads together and setting
the ohmmeter reading to zero. Then check the
stator continuity by connecting the meter leads to
the stator leads as shown in Figure 5-4.
Note: Leads 1, 2, 3, and 4 are the generator output
leads. Leads 11, 44, 55, and 66 are the
controller and SCR module sensing and
TP-6196 5/04
Moving rotor.
Do not contact electrical
supply leads. Refer to the schematic in
Figure 5-5 when performing the following
steps.
6. Contact the ohmmeter leads and readjust the
ohmmeter to read zero ohms.
Figure 5-4 Testing Stator Windings
4
3
66
55
2
1
Figure 5-5 Alternator Stator Leads
7. Check the cold resistance of the stator windings by
connecting the meter leads to stator leads 1-2, 3-4,
and 55-66. See Section 1.6, Alternator, for stator
winding resistances.
provide accurate readings below 1 ohm.
resistance readings (continuity) and no evidence of
shorted windings (heat discoloration) indicate a
stator in good condition. See Figure 5-6.
8. If the resistance test proves inconclusive, use a
megohmmeter to test the stator as described in the
next step.
Note: Because ohmmeter
resistance
readings. Take readings of the rotor and
stator at room temperature.
Note: Make sure that all stator leads are
disconnected
megohmmeter test.
Section 5 Component Testing and Adjustment
R14807-14
44
11
Most ohmmeters do not
accuracy varies,
readings are approximate
before running
6196
Low
the
41