Nidec 22765-01, Руководство пользователя

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Test Lamp: Connect the leads of a test lamp, consisting of standard
flashlight batteries and a flashlight and built, as shown in Figure 22,
across the rectifier in one direction. Then reverse the leads. The light
should light in one direction but not the other. If the light lights in both
directions, the rectifier is shorted. If the light does not light in either
direction, the rectifier is open.
Figure 22 Test Lamp
Replace defective rectifiers with rectifiers of the same operating
characteristics as rectifiers installed in the generator at the factory.
Order rectifiers by part number, including the model and type of exciter
as well as the generator serial number.
Surge protectors may be included on the rotating rectifier assembly.
Disconnect one lead of the surge protector, and connect the leads of
an ohmmeter or makeshift test lamp, consisting of standard flashlight
batteries and a flashlight and built as shown in Figure 22, across the
surge protector in either direction. If the light comes on, the surge
protector is defective. Order surge protectors by part number, including
the model and type of exciter as well as the generator serial number.
Following replacement, make sure that the revolving field, exciter
armature, and rotating diode leads are properly secured.
Ohmmeter: Connect the ohmmeter leads across the rectifier in
one direction (see Figure 21). Note the meter reading. Reverse the
leads, and note the meter reading. The meter should indicate a low
resistance when the leads are across the rectifier in one direction and
a high resistance when the leads are across the rectifier in the opposite
direction. A low resistance in both directions indicates a short. A high
resistance in both directions indicates an open rectifier.
Reverse
diode
Standard
diode
Anode
Cathode
Ohmmeter
Figure 21 Testing the Rotating Rectifier with an Ohmmeter