Alternator Exciter Wire Light

[RODALCO]

The rotor draws between 0.5 and 4 Amps. Depends upon what the output load of the alternator is.
DC resistance is around 3 Ohms.
For 10 Amp load my guess is around 1 Amp value.

 

[RODALCO]

I have a circuit somewhere in my archives in which I used in an Australian made Ford Falcon for 12 years with no problems at all.
The Email alternator died which had an external electro-mechanical regulator, and I used an old Renault Paris-Rhone alternator
It uses a 2N3055 transistor, Zener and a few other parts.
Excitation is via a 3 Watt lamp.
I look for it and will post it.

 

[spec]

The rotor draws between 0.5 and 4 Amps. Depends upon what the output load of the alternator is.
DC resistance is around 3 Ohms.
For 10 Amp load my guess is around 1 Amp value.

I have a circuit somewhere in my archives in which I used in an Australian made Ford Falcon for 12 years with no problems at all.
The Email alternator died which had an external electro-mechanical regulator, and I used an old Renault Paris-Rhone alternator
It uses a 2N3055 transistor, Zener and a few other parts.
Excitation is via a 3 Watt lamp.
I look for it and will post it.

Thx- you obviously know about alternators. I would like to see your regulator circuit.

spec

 

[RODALCO]

Hi spec, I have worked a lot with alternators, generators and starter motors before I ventured in the High Voltage power industry in the late 1988's .

I did find the old schematic which I found in an old Electronics Australia magazine from the early 1980's.
also redrawn it on a clean piece of paper as the glue has printed through the edges.

Some alternators give clean external access to the brushes which is perfect for this circuit as a simple 2N3055 transistor can be used which is cheap and reliable.

I also fitted this circuit in a V8 Rover P5B with a Lucas alternator which is still running fine,

and must have been in service for over 20 years.

 

[spec]

Hi spec, I have worked a lot with alternators, generators and starter motors before I ventured in the High Voltage power industry in the late 1988's .

I did find the old schematic which I found in an old Electronics Australia magazine from the early 1980's.
also redrawn it on a clean piece of paper as the glue has printed through the edges.

Some alternators give clean external access to the brushes which is perfect for this circuit as a simple 2N3055 transistor can be used which is cheap and reliable.

I also fitted this circuit in a V8 Rover P5B with a Lucas alternator which is still running fine,View attachment 100095 View attachment 100096 and must have been in service for over 20 years.

Thx RODALCO: interesting, informative and useful.

spec

 

[debe]

This is a Voltage regulator & circuit for an 80Amp Bosch altenator.

 

[debe]

This is a Bosch altenator circuit to suit the above regulator. The CRO waveform is the voltage across the Rotor.

 

[spec]

Thx to you too debe- very informative.

spec

 

[RODALCO]

Thanks for that schematic too, great for alternators where the negative of the rotor is direct on the ground. Brilliant work in unpotting that Bosh regulator.

 

[spec]

Hy debe,

I know it is probably obvious to most of you, but you couldn't describe what the scope trace is showing: where it is connected and also what current the alternator is supplying.

spec

 

[debe]

The scope trace is the voltage a cross the field. In the circuit above the .047uf cap & 1k resistor provide a feed back circuit to make the circuit oscillate to reduce the heating of the output transistor.

 

[debe]

This is the current draw on the Field circuit of a 60A altenator with very little load & then about 45Amps.

 

[debe]

This is the circuit of a Lucas altenator, the field on these is fed voltage straight from the field feed diodes. Ive added the circuit values when I dismantled one of these regulators.

 

[spec]

Hell debe,

You know your alternators.

spec

 

[debe]

This is the wave form across the Field windings. One is a load of about 5A & the other about 20A. What changes is the frequency & the Duty cycle.

 

[RODALCO]

Thanks debe for your excellent photo's and scope images.
It proves also my data re the rotor current varying between 0.5 and 4 Amps.