804 Alternator charging ckt help please ?

[mciikurzroot]

I'm having a sr moment brain lapse. The battery charging alternator is i'd say a 2 wire style , but actually 3 .. One wire is ground, so that is pretty self explanatory, one wire is the actual OUTPUT wire, and 1 wire is IGN designated.. it was my belief that this alternator is "excited" or switched on when the IGN wire is matched to the normal 24vdc voltage of the set thereby exciting the alternator to produce upwards to 30 vdc or as the battery voltage reference is requiring to become fully charged after engine starting, so effectively placing the IGN wire onto any convenient system plus voltage as a pick up or voltage point... Do I have the outline or overall process right or am i missing a part i have forgotten...
thank you: mac/mc MCII

 

[Guyfang]

Mac,

Did not see this till now. You have it right.

 

[mciikurzroot]

Well thank you GF i was asking for a friend who
set was not charging, but now it seems the same has happened to me as well, im stumped as the schematic depicts seemingly if you close 248 and 164 together then the alternator should start charging drained batteries until the batteries reach a charged point as determined by the internal regulator within the alternator... but thats not happening for me and im stumped... SUGGESTIONS welcomed, keep in mind i have removed all the shunt and meter wiring, but this should still allow the alternator to charge when IGN # 248 and Bat 164 are connected, but no charging at all, YES the alternator checks good made a special trip into my alternator shop just to confirm the alternator is good ... thanx mac/mc mcii

 

[kloppk]

Might it be the alternators BAT terminal need to be connected to 24V BEFORE the IGN terminal gets 24 V?

 

[mciikurzroot]

Good suggestion and one ill try within the next few hours but i can see where this sorta makes some sense, so yah ill try for it thanx for the suggestion...