Kohler 11RMY, Руководство по обслуживанию

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TP-5867 11/02 40 Section 6 Component Testing and Adjustment
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.
Grounding electrical equipment. Hazardous voltage can
cause severe injury or death.
Electrocution is possible
whenever electricity is present. Open the main circuit
breakers of all power sources before servicing the equipment.
Configure the installation to electrically ground the generator
set, transfer switch, and related equipment and electrical
circuits to comply with applicable codes and standards. Never
contact electrical leads or appliances when standing in water
or on wet ground because these conditions increase the risk of
electrocution.
Rotor Test Procedure
1. Place the generator set master switch in the OFF
position.
2. Disconnect the generator set engine starting
battery, negative (--) lead first.
3. Disconnect power to the battery charger, if
equipped.
4. Remove the brush cover from the alternator end
bracket.
5. Check the rotor for continuity and resistance.
Raise the brushes from the slip rings while
performing ohmmeter tests.
Measure the rotor
resistance (ohms) between the two slip rings; see
Figure 6-9. See Section 1.3, Generator, for rotor
resistance readings. If the resistance readings are
low, perform a megohmmeter test on rotor as
described in the next step.
Note: Because ohmmeter accuracy varies,
resistance readings are approximate. Take
readings at room temperature.
2-221
R13929-7
Figure 6-9 Rotor Resistance Check
6. Perform a megohmmeter test to determine
whether the rotor is shorted to ground.
a. Raise and secure the brushes away from the
slip rings by inserting a retaining wire in the
brush holder hole.
b. Using a megohmmeter, apply 500 volts DC to
one rotor slip ring and the rotor poles or shaft.
Follow the instructions of the megohmmeter
manufacturer when performing this test.
Note: A reading of approximately 500 kOhms
(1/2 megohm) or higher indicates a
good rotor.
c. Repair or replace the rotor if the reading is less
than approximately 500 kOhms. A reading of
less than 500 kOhms indicates deterioration of
the winding insulation and possible current flow
to ground.
d. Following the test, remove the retainer wire
from the brush holder and check the brush
positions on the slip rings. See Section 6.6,
Brushes.
e. Reinstall the brush cover on the end bracket.
6.4.2 Slip Rings
Slip rings acquire a glossy brown finish in normal
operation.
Do not attempt to maintain a bright,
newly-machined appearance on the slip rings. Cleaning
with a dry, lint-free cloth is usually sufficient. Use very
fine sandpaper (#00) and apply light pressure to remove
roughness. Do not use emery or carborundum paper or
cloth. Clean all carbon dust from the generator after
sanding the slip rings. If the rings are black or pitted,
remove the rotor and use a lathe to remove some of the
slip ring surface material.
6.5 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 the 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.