generic externally regulated alternator connection

[fitterski]

I need to rephrase my original question. The alternator I have is an externally regulated model suitable for a 1995 Ram diesel pickup (the engine it's going to). It has 2 unmarked field terminals. In the case of that truck I /think/ the external regulator is actually he external vehicle PCM module so that one field terminal on the alternator gets full 12 volts from the system and the other one goes to the PCM where it is then reduced if needed and then grounded (regulated).

I don't have a PCM, I have a generic ford-compatible electronic 4-terminal (I-A-S-F) external regulator.

"I" normally goes to ignition which I do not have, it could be a light which I do not need, ergo "unused"
"A" is where regulator gets 12v, connect to batter or BAT terminal of alternator
"S" supposedly goes to STATOR, not sure about purpose/use of this one
"F" what is the exact function of the F terminal?

Case-1: my 4-terminal external regulator acts like the external PCM so one of the 2 alternator field terminals gets battery 12v (from any source) and the other goes to the regulator F terminal inside which the voltage subsequently gets reduced if required before being grounded (regulated). In this case the F terminal does NOT SUPPLY.

Case-2: the 4-terminal external regulator F terminal PROVIDES already regulated voltage in which case it gets connected to one of the 2 alternator field terminals (same as above) but then the other alternator field terminal must be just grounded to alt-regltr-frame.

I don't wanna blow the regulator with a + to + connection as soon as powered, nor blow up the battery because all it really gets is 16-17v which result from continuous un-reduced 12v going the the alternator F terminal all he time.

 

[Agvg]

Again several replies, I have checked 'subscribe' to be emailed but got none.

I understand that internal/external reliability is similar but if an external one blows you don't need to replace the alternator. Meanwhile I presume that mechanical ones are more reliable. There is a warning (below) to "never disconnect a battery terminal with engine running'. Remember when this WAS the standard way to test an alternator? We probably still doe not need this warning with mechanical ones(?).

I went to the local supplier and the only alternator with a tach-tab he has in stock is 3-wire one for $400cdn (not ready to buy one of those!).

Meanwhile I received the external regulator I ordered. It's electronic and compatible with ford (mechanical or electronic) which I guess is generic enough. Unfortunately ABSOLUTELY NO DOCUMENTATION, it has 4 tabs: I, A, S, F plus a warning note and that is it.

To run an alternator and then disconnect the battery has never been a test method, and you are not taking out the regulator but are risking to kill the rectifier diodes.

 

[fitterski]

To run an alternator and then disconnect the battery has never been a test method, and you are not taking out the regulator but are risking to kill the rectifier diodes.

My mistake, I should have said generators, Alternators began showing up in the 60's, generators had no diodes

 

[fitterski]

I put this 100 amp one wire on a old ford last year.
View attachment 628157

I like the 1-wire idea, it cannot get any simpler than that! That leaves only the physical mounting to match:

Selecting an Alternator | West Marine

Mine is a 2" spindle so I would be interested in a 1-wire Delco-Remy with in addition a tach (AC) output with a grooved-belt pulley (or the option to change pulley)

 

[lennyzx11]

Here’s a little more information if you want it.

MAD enterprise has been gurus in automotive electrics for years.
They have quite a bit of information to share on their web site.
Specifically, read the 3 wire or one wire articles.
Catalog

I’m interested in this thread as I am just finishing up converting my 64 Ford 2000 gasser to 12 volt.
After researching quite a bit, I found it easier to buy a “kit”. Mine came from Yesterday’s Tractor.

Here’s an old thread that I hope is allowed here with some useful information.

Yesterday's Tractors - Step by Step 12-Volt Conversion

Though mine is installed as a one wire from the kit, I’m going to wire in the indicator light.
When I tested it though, it did immediately start charging at 14.4 volts at idle. I was worried about that having to rev it up to start charging. That’s a half assed way to do things.

 

[fitterski]

When I tested it though, it did immediately start charging at 14.4 volts at idle. I was worried about that having to rev it up to start charging. That’s a half assed way to do things.

from what i understand the new alternators' charge voltage depends on the battery condition, around 14 being the minimum and it climbs for a more discharged battery

 

[Grumpycat]

I payd CAD $7 for a new internal regulator for a Delco 10 SI at the local automotive store. The Delco 10SI is probably the easiest alternator to work on! No soldering at all.

Yes and you can usually buy new brushes too. And bearings.

 

[fitterski]

..I went to the local supplier and the only alternator with a tach-tab he has in stock is 3-wire one for $400cdn (not ready to buy one of those!)..

I showed him the 1-wire chinese knockoff with an R teminal on amazon for $116cdn and he immediately found a real ACDelco available for $10 more. It should be here in 4 days or so:cool2: