wiring an external regulator

[frogcase2002 393]

Alright im hooking up an external regulator (One of them blue boxes) to a second alternator that is separate from the vehicles electrical. . There is 3 pins in the plug on the alt but right now there is just one wire going to it to turn it on. ..  The problem I am having is I dont know where to hook the field wire from the regulator to . I have tried the all the pins in the plug of the alt but nothing is making the regulator work .  . 

 

Vehicle is an 08 escalade and the alt is a dc 370

[frogcase2002 393]

I need to find where the field wire is on an internally regulated alt . 

[Randal Johnson 544]

Why are you setting this up separately ?? Different charging voltage ???

[frogcase2002 393]

Thats what the guy wants .  Said his computer in the car alot of the time is makes it just charge at 12 something

[Randal Johnson 544]

If that alternator is set at 13.6 (normal 12 volt charging), there is no need for a voltage regulator. 

If that's a DC alternator, ask the manufacturer for a wiring diagram.