Voltage Regulator Wiring Differences

[TenSeven]

The markings on Ford voltage regulators differ. Some are F234, some are IASF. On a typical Delco 3 wire alternator with connection markings of FLD,BAT,STA and GRD, how would either of those two regulators be connected?

For example,

F->FLD
2->
3->
4->

I->
A->
S->
F->FLD

 

[RonD]

BAT or B+ is easy, that connects directly to the Battery +(positive), thru a Mega Fuse or Fusible link.

STA = Stator, these are the 3 stationary windings in the case of the alternator, the spinning rotor's electro-magnetic fields generate AC voltage in the Stator, this AC voltage is converted to DC voltage via 2 Diodes per winding.
This is B+


I = ignition switch, it gets power when key is turned on, the power passes thru the Battery Light in the dash, this is the ON/OFF switch for the alternator.
An alternator draws power when it isn't generating power so need to be turned OFF.
This power draw is seen when Battery Light comes on, power is passing thru the bulb to the alternator so it lights up, when alternator starts to generate power then no power is passing thru the bulb so it goes off.
(one wire alternators use an internal RPM switch for this, which shuts off alternator when RPMs drop below set threshold, so battery won't drain when engine is off)

F = Field voltage, the fields are electro-magnets in the rotor.
The field voltage is applied to the rotor thru brushes, the amount of voltage sent to the fields determines the amount of voltage that comes out at B+.
So the Voltage Regulator controls the Field voltage, example: 8 volts going to field would produce 14volts out at B+ assuming alternator is spinning at 2,000 RPM(alternator, not engine), the gain in voltage is from engine power.

S= Sensing voltage, this is part of voltage regulator circuit, it connects directly to Battery + as well, via a fuse or fusible link.
This is how the voltage regulator monitors system voltage so it knows how much voltage to send to the Field.

GND is of course the Ground, usually just the mounting bolts for alternator but many add another Ground wire.
With separate voltage regulator then ground between alternator and regulator should be wired

Never ran into an old Ford with F234

GM yes
F = Field, to alternator
2 = R, to alternator
3 = S, sensing voltage, from battery
4 = I, ignition ON/OFF, from key switch

Opps

Forgot IASF
I = ignition, to key switch
A = B+
S = sensing, to battery
F = Field

 

[TenSeven]

Thank you Ron, great info, I appreciate it.

That solves a bit of a mystery.

On a project I have Ranger 2.8 in a Sunbeam Alpine. The 2.8 came with a newer 3 wire Delco alternator. I found an article that shows how to use a Delco alternator in an Alpine using a Delco voltage regulator but thinking along the lines of my Ford 2.8 alternator I bought an 85 Ranger 2.8 voltage regulator, which is apparently different (at least in markings) from the Delco regulator.

http://teae.org/fitting-a-delceries-v-alpine/

The article diagram shows the 3 wire connection to the alternator but the alternator markings show F (FLD), BAT, and R? Going to the (Delco) regulator #2 connection.

I've been trying to figure out how to use the Ford regulator when apparently I should be using a Delco regulator?

 

[RonD]

There should be just 2 wires from an external Regulator to the alternator, 3 if you count the Ground wire, which should be used.

Field
And the confusing one, lol, R, A or S because depending on the model/year they change, S is for Stator in this case, it is basically the same as B+
Alphabet soup

This connection is almost always next to the Field wire connector, labelled #2, S or A

But yes, getting a similar year Delco Voltage regulator for the Delco alternator would be best.

 

[TenSeven]

Geez, ya, confusing, especially when following a diagram but have a different regulator than depicted

Anyhow, so the diagram does look to be correct in that it does show only two connections to the alternator from the regulator.

So, using the correct regulator this time, #2 would connect to the STE (S/R) post on the alternator I have.

Thank you Ron.

 

[TenSeven]

One other thing, I noticed in the article the author writes to connect not only connect F to F, but also connect #2 to F, yet the diagram shows #2 being connected to R?

 

[RonD]

#2 would probably have 12v, depends on regulator
That would set alternator at MAX output voltage all the time, 15+volts, and that can "cook" a battery over time.

The whole point of the voltage regulator is so battery stays charged but doesn't "cook", boil away chemicals inside.
13.5volts maintains a 12volt battery charge without cooking it, 14.5-15volts recharges battery after starting engine, so you often see 15volts just after starting but it should drop down to about 13.5v after a few minutes, that's the voltage regulator working.

Field voltage is 5 to 9 volts, that goes into the rotor, and that sets the output voltage you get from B+, Field voltage is what regulator controls

 

[TenSeven]

#2 would probably have 12v, depends on regulator
That would set alternator at MAX output voltage all the time, 15+volts, and that can "cook" a battery over time.

The whole point of the voltage regulator is so battery stays charged but doesn't "cook", boil away chemicals inside.
13.5volts maintains a 12volt battery charge without cooking it, 14.5-15volts recharges battery after starting engine, so you often see 15volts just after starting but it should drop down to about 13.5v after a few minutes, that's the voltage regulator working.

Field voltage is 5 to 9 volts, that goes into the rotor, and that sets the output voltage you get from B+, Field voltage is what regulator controls

Thanks.

Des that mean the diagram is correct (#2-R, or S on my alternator), but what he wrote in the article is wrong? (#2->F)

 

[RonD]

Models and years

Things change, can't say it is wrong because for that model regulator with that model alternator it might be right.

 

[TenSeven]

Models and years

Things change, can't say it is wrong because for that model regulator with that model alternator it might be right.

Fair enough my friend, appreciate the help.