Briggs & Stratton 86262GS, Руководство по ознакомлению и устранению неисправностей

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Before testing the rotor, inspect the brushes and slip rings.
Replace brushes if they are worn excessively, or if they are
cracked or damaged. Do not use any metallic grit to clean up
slip rings.
To test the rotor with a volt-ohm-milliameter VOM, set the
VOM to its “OHM” scale and zero the meter.Then, test for
an open, shorted or grounded condition as follows:
•• Step 1 Checking Rotor Resistance
• Remove the brush assembly.
• Set the VOM to its “OHM” scale.
• Connect the test leads to the rotor slip rings
(See Figure 3.37).
Because of the cramped quarters inside the rear bearing
carrier, it is necessary to remove the power cable grommet
as shown in Figure 3.38.
Measure the rotor resistance and compare it to the nominal
resistance from the appropriate resistance table (Briggs &
Stratton Power Products
®
“Portable Generator Rotor/Stator
Resistance Tables Pub. #87971 Rev 6 or later).
A reading of “infinity” or a very high resistance indicates an
open circuit or a partially open condition in the rotor
windings.
A very low resistance indicates a
shorted rotor.
• Connect one test lead to the rotor shaft and the other
test lead to either rotor slip ring (Figure 3.39).
A reading of “infinity” should be measured. A reading other
than infinity indicates a rotor winding shorted to the rotor
shaft.
NOTE:
Sometimes a rotor may only fail while it is
spinning at rated RPM.This condition is called a
“Flying Open” or “Flying Short.”
80
Section 3 • Generator Diagnostics and Adjustments
Portable Generator Familiarization & Troubleshooting Guide
Replace Rotor
Replace Rotor
Replace Rotor
Grommet
Removed
For Access
Figure 3.38 — Access To Rotor Slip Rings
Figure 3.37 — Checking Rotor Resistance
Figure 3.39 — Checking Rotor Short To Ground