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Grinkle
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- Odd looking 12V waveform on my alternator - I suspect the regulator, and I want to energize the alternator bypassing the regulator to see if that cleans things up
I have a "house" alternator on my van. The 12V rail waveform is attached. The 5V drop-outs are not right, imo.
The alternator is controlled by a Balmar 614 regulator.
http://www.balmar.net/PDF/regulator info s/MC-614.pdfThe spacing of the drop outs leads me to suspect they are synchronous with the state control switching of the voltage regulator - I doubt the belt speed would produce spikes that are 2ms apart like that, it seems more like the micro-controller frequency is driving the spacing of these drop outs. Moreover, changing the van engine idle speed does not change the spacing of these drop outs. I suspect the output of the regulator that is driving the alternator field is not right. If my understanding is correct, its a pwm current output, not a voltage output, so maybe hard to monitor directly.
What I want to do is run the alternator without the regulator attached at less than full field and see if the 12V rail is clean. I am concerned about doing a full field test - I don't want to damage the alternator. The field strength is regulated by a PWM input coming from the regulator pin 4. The regulator manual says one can do a full field test by removing that connector and shorting pin 4 to the 12V rail - I guess that will saturate the coil in the alternator. I don't want to do that - conceptually I'd like to connect the field input to a bench supply and ramp it up slowly to see the output current from the alternator come up and see if its clean / stays clean as I ramp up the field current.
Any thoughts on the wisdom or folly of thei below approach much appreciated.
"connector" in my description below means pins 1-4 shown on page 3 of the regulator manual, there is a picture of "connector" on page 2 of the manual.
Step 1 is to disconnect the connector from the regulator, so the regulator is unpowered and the alternator field is unpowered. I have confirmed this just leaves a clean 12V battery output on the rail with the engine idling - the regulator is dark, and the alternator is spinning freely, field not energized.
I am thinking to take a bench supply, set it to 12V, set the current compliance very low, and use the bench supply to energize the field by conntecting it to the alternator field input with the the plug disconnected from the regulator (so I would just connect the bench supply to pin 4 of that connector, the ground of the bench supply to pin 1 of that connector, and leave pins 2 and 3 floating). I think the alternator will collapse the bench supply if I set the compliance to a few hundred uV and the bench supply will be acting as a current source until I increase the compliance enough to saturate the alternator. I'm not sure how much current will saturate the alternator coils.
Thanks in advance for any advice. I am hoping someone here may have prior experience with alternators and can tell me if my thinking makes any sense.
The alternator is controlled by a Balmar 614 regulator.
http://www.balmar.net/PDF/regulator info s/MC-614.pdfThe spacing of the drop outs leads me to suspect they are synchronous with the state control switching of the voltage regulator - I doubt the belt speed would produce spikes that are 2ms apart like that, it seems more like the micro-controller frequency is driving the spacing of these drop outs. Moreover, changing the van engine idle speed does not change the spacing of these drop outs. I suspect the output of the regulator that is driving the alternator field is not right. If my understanding is correct, its a pwm current output, not a voltage output, so maybe hard to monitor directly.
What I want to do is run the alternator without the regulator attached at less than full field and see if the 12V rail is clean. I am concerned about doing a full field test - I don't want to damage the alternator. The field strength is regulated by a PWM input coming from the regulator pin 4. The regulator manual says one can do a full field test by removing that connector and shorting pin 4 to the 12V rail - I guess that will saturate the coil in the alternator. I don't want to do that - conceptually I'd like to connect the field input to a bench supply and ramp it up slowly to see the output current from the alternator come up and see if its clean / stays clean as I ramp up the field current.
Any thoughts on the wisdom or folly of thei below approach much appreciated.
"connector" in my description below means pins 1-4 shown on page 3 of the regulator manual, there is a picture of "connector" on page 2 of the manual.
Step 1 is to disconnect the connector from the regulator, so the regulator is unpowered and the alternator field is unpowered. I have confirmed this just leaves a clean 12V battery output on the rail with the engine idling - the regulator is dark, and the alternator is spinning freely, field not energized.
I am thinking to take a bench supply, set it to 12V, set the current compliance very low, and use the bench supply to energize the field by conntecting it to the alternator field input with the the plug disconnected from the regulator (so I would just connect the bench supply to pin 4 of that connector, the ground of the bench supply to pin 1 of that connector, and leave pins 2 and 3 floating). I think the alternator will collapse the bench supply if I set the compliance to a few hundred uV and the bench supply will be acting as a current source until I increase the compliance enough to saturate the alternator. I'm not sure how much current will saturate the alternator coils.
Thanks in advance for any advice. I am hoping someone here may have prior experience with alternators and can tell me if my thinking makes any sense.