Rotor Inspection - Bosch T1 Alternator Repair And Testing Instructions

9.15 Rotor Inspection

1. Using electric tester ETE 014.00 or Multimeter MMD 302, measure the resistance between the two collector
rings of the rotor. The resistance measured should be between 7.5 and 8.3 . (Figure 21)
2. Using insulation tester KDAW 9983 or equivalent, apply 80 VAC to the rotor claw poles and each of the
collector rings. If the insulation tester lights, there is a short to ground within the rotor. (Figure 22)
Note: The insulation tester applies a voltage of 80 VAC to the rotor. Voltages of 80V can be fatal.
When performing this test, observe care is used in handling the rotor and any component or surface
that is exposed to the rotor. Use insulated gloves and do not touch the work surface until all tests are
completed.
3. Mount the rotor in a pair of V-Blocks at the rotor bearing points.
All rights rest with Robert Bosch Corp, including patent rights. All rights of use of reproduction and publication rest with R. B. Corp.
UA/ASV
Repair and Testing Instructions for T1
Alternator 0120 689 552
04.12.98
Figure 21 Rotor Resistance Testing
Figure 22 Rotor Insulation Testing
T1ALTFinal.DOC
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