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Alternator troubleshooting
Symptom
Possible cause
Corrective action
Alternator gives 0 Volt
Blown fuse.
Replace fuse.
No residual voltage.
Excite the alternator by applying a 12V battery voltage with a 30
resistor in series on the +
and - terminals of the electronic regulator, respecting the polarities.
After being excited the alternator still gives 0 Volt.
Connections are interrupted.
Check connection cables, measure winding resistances and compare with values mentioned in
the alternator manual.
Low voltage at no load
Voltage potentiometer out of setting.
Reset voltage.
Intervention of protection.
Check frequency/voltage regulator.
Winding failure.
Check windings.
High voltage at no load
Voltage potentiometer out of setting.
Reset voltage.
Failed regulator.
Substitute regulator.
Lower than rated voltage at load
Voltage potentiometer out of setting.
Reset voltage potentiometer.
Intervention by protection.
Current too high, power factor lower than 0.8; speed lower than 10% of rated speed.
Failed regulator.
Substitute regulator.
Rotating bridge failure.
Check diodes, disconnect cables.
Higher than rated voltage at load
Voltage potentiometer out of setting.
Reset voltage potentiometer.
Failed regulator.
Substitute regulator.
Unstable voltage
Speed variation in engine.
Check regularity of rotation.
Regulator out of setting.
Regulate stability of regulator by acting on STABILITY potentiometer.
Содержание QAS 250-330 JD T4i
Страница 1: ...QAS 250 330 JD T4i Instruction Manual for AC Generators English ...
Страница 2: ......
Страница 19: ... 19 This is the described menu flow for changing the unit type ...
Страница 63: ... 63 Dataplate ...
Страница 65: ... 65 Circuit diagrams ...
Страница 66: ... 66 1310 3200 12 00 Applicable for QAS 250 330 Qc1002 Engine Circuit ...
Страница 67: ... 67 ...
Страница 69: ... 69 1310 3200 11 00 Applicable for QAS 250 330 Qc2002 Power Circuit ...
Страница 70: ... 70 ...
Страница 72: ... 72 1310 3200 13 00 Applicable for QAS 250 330 Wiring Diagram Control panel wiring ...
Страница 74: ......
Страница 75: ......
Страница 76: ...www atlascopco com ...