I have just blown my second alternator in 3 years. Its the type that the field winding is controlled by the engine management chip.
The controller is OK I'm thinking but the two alternators show different signs and I am trying to get one to work.
"A" gives an output voltage of up to 18 volts when run as fast as my drill can turn it and the field is taking about 4 amps directly through my bench supply at 12 Volts. Can't get it over 18V but my drill is a bosch 1200 watt on 240 V so I guess its doing about 900 rpm or less
"B" gives no output at any speed and takes about the same amperage through the field winding .
I have checked all the diodes and all seem to be working fine.
I have noted that on "B" None of the windings show a resistance at all and show continuity with a buzzer. I havn't checked "A" diodes again but they seemed OK the first time I checked them. However the windings again gave no resistance however I checked them , just continuity.
Can anyone lay out a definitive check routine so I can locate the faults?
With the 3 windings being joined at the star center I would have thought some sort of testable resistance should show if I can get continuity between any two windings
The controller is OK I'm thinking but the two alternators show different signs and I am trying to get one to work.
"A" gives an output voltage of up to 18 volts when run as fast as my drill can turn it and the field is taking about 4 amps directly through my bench supply at 12 Volts. Can't get it over 18V but my drill is a bosch 1200 watt on 240 V so I guess its doing about 900 rpm or less
"B" gives no output at any speed and takes about the same amperage through the field winding .
I have checked all the diodes and all seem to be working fine.
I have noted that on "B" None of the windings show a resistance at all and show continuity with a buzzer. I havn't checked "A" diodes again but they seemed OK the first time I checked them. However the windings again gave no resistance however I checked them , just continuity.
Can anyone lay out a definitive check routine so I can locate the faults?
With the 3 windings being joined at the star center I would have thought some sort of testable resistance should show if I can get continuity between any two windings
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