Alternator and regulator wiring

Jassira

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Egham, Surrey
www.jassira.com
I have a 24v CAV alternator (AC5 or AC7 I think) for various reasons I disconnected it and can't find my notes to reconnect the alternator to the regulator. It looks fairly simple, there are two large black cables from the alternator , marked "B-" & "B+" which I presume go to the battery and two smaller red cables which need to connect to terminal "A" and terminal "F" on the regulator. The A&F are clearly marked on the regulator but I have no ideal which of the two red cables from the alternator are which.
My plan is to connect the battery cables start the engine without the two smaller cables connected and ideally, using a multi metre, measure something to establish which is which alternatively just a guess which way round they go and see what happens.
So my questions are

A) Will powering things up for a short period without these cables connected cause an issue.
B) What, if anything, can I measure with the multi metre.
C) Will I damage something if I get them the wrong way round ?

Thanks in advance for your advice.
 
I think F and A terminals on the regulator should be connected to the field and armature windings. If there are no corresponding markings on the alternator, perhaps you can open it up a little? Field winding is usually the rotor, so that cable should connect to one of the brushes, I believe.
 
I think F and A terminals on the regulator should be connected to the field and armature windings. If there are no corresponding markings on the alternator, perhaps you can open it up a little? Field winding is usually the rotor, so that cable should connect to one of the brushes, I believe.
A = ammeter in a classical regulator?
FADE
Field, ammeter, Dynamo, Earth.
Usually WL or W for 'charge light' AKA ignition light.
Filed is indeed the rotor, i.e. one of the brushes. But the other brush can be either +ve or -ve, connected internally if the rectifier is internal.

On the alternator, B or B+ is the output, usually easy to tell, it's the big one.
 
A = ammeter in a classical regulator?
FADE
Field, ammeter, Dynamo, Earth.
Usually WL or W for 'charge light' AKA ignition light.
Filed is indeed the rotor, i.e. one of the brushes. But the other brush can be either +ve or -ve, connected internally if the rectifier is internal.

On the alternator, B or B+ is the output, usually easy to tell, it's the big one.

A lot of confusion on various markings... Some further research suggest that A on the regulator should more likely connect to battery positive (B+ on the alternator). A cable for the armature would problably have been marked S (for stator), I think.
 
I'd expect there to be three connections between the regulator and the alternator, but maybe the case makes the earth connection ?
 
Thanks for that, nice diagram that I've saved for future reference.
I did find my diagram eventually but was still left with the problem of which of the large cables from the alternator was which. I ended up stripping the alternator to establish which was the from field winding...
 
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