Alternator charging delay on start up?

[bljones]

Where/how are you measuring output?

[capn_dave]

If that's the case, you have a self exciting alternator. That is, the Alternator will not turn on until the engine reaches a set rpm. It has to make it's own magnetic field. Once it starts charging, it will keep charging nomatter the rpm. Typically you start the engine, rev the motor slightly and alternator starts charging. I think it is the SI series alternator that does this.
With the CS series delco alternator with the self exciting voltage regulator you do not need to rev the engine.

Fair Winds

Dave

[aeventyr60]

Output measured 2 ways, One through a link 2000 meter and the other through a traditional amp meter and voltmeter...engine instrumentation..Amp meter is redundant.

Wiring.
Positve to Starter(6 Ga wire) then to 1, 2 both switch(00 ga. wire)
Negative to starter.
2 wire regulator-plugs into alternator, I think back to starter, late night now, will confirm
Funky 2 wire push on connection that goes into engine wiring harness-Think RPM and engine volt gauge.

[jrd22]

I'm with Capn Dave, sounds like a single wire alternator. Many of the large trucks I've owned did the same thing, no charge after starting until the rpm was raised slightly, then normal charging. These were mostly large case alternators on large diesel engines.

[aeventyr60]

Maybe will have to live with this one. Thanks for your replies.

[donradclife]

Many alternators are designed to work with an idiot light. The idiot light comes on when you turn the ignition on and goes off when the alternator starts putting out. What a lot of people don't understand is that the current going through idiot light is used by the regulator to start the charging process. Here is a good explanation

Understanding Alternators, How Alternators Work