So explain how H injection doesn't work again?

[joeventura]

So a single wire to the Alternator (shown here) does what you describe yes?

[severach]

Originally Posted by joeventura

Is the alernator powering the devices in the car or is it charging the battery that powers everything?

To the car this doesn't matter. All that matters is that the necessary power is supplied. To you it only matters slightly since there is a bit of loss to put power into a battery and pull it back out. It would cost more to put all the energy into the battery then pull it back out than to use it directly from the alternator.

What happens to the 10 amps I don't use?

If the alternator field were from a permanent magnet then the power would need to be discarded. Your alternator, like a generator in a power plant, has an electrically variable field controlled by a regulator. The power never got produced nor was that extra power drawn from the belt.

Next question, same scenario, I have everything on and drawing 30 amps and turn on a HHO generator that draws 20 amps. Do the lights dim or does the battery start to drain (probably both)

For a 40 amp alternator that is actually limited to 40 amps, it will produce 40 of the amps and the battery will supply the other 10. Run for a while and your lights will dim and eventually everything will go out. Alternator ratings have gone up as gewgaws have gone up because that situation must not happen so long as the alternator is operating properly.

but here is the $64 question, does the alternator do anything different? Turn faster? Work harder? I think not.

It works harder at the direction of the regulator. The regulator increases the field current to produce more power at the same speed. If you speed the engine up then the faster alternator will produce more power so the regulator will reduce the field to compensate.

My understanding is the alternator is turning and creating power, which is either stored or used, and when the battery is fully charged and the devices are not drawing more than the alternator can make then the extra power goes where?

If there is no field current then the spinning alternator produces no power, just some air noise and bearing heat. You have witnessed this when the alternator brushes are at the end of their life and no longer make contact. The battery dies rather quickly even though there is a spinning alternator connected.

My point is that the alternator is creating power in excess of the cars needs probably better than 50% (if not more) of the time, so if you use it for a radio, an HHO generator, a winch, etc as long as the car is running and your battery is in good shape then what is the problem?

If a 125 amp alternator were producing 125*12=1500 watts wasting and you were only using 30 amps then the wasted 95*12=1180 watts should be easy to find. Something near the alternator would be glowing red. Don't look, it isn't there. The alternator only produces what is needed.

Originally Posted by RoadWarrior

That's only true of older cars. Since the 80s the ECU has been modulating the field current of alternators according to load.

An ECU is not required to regulate an alternator. Regulators have been used with alternators for a very long time, long before 1980 and ECUs. All the ECU does is to monitor the load and may temporarily reduce or pause production from time to time. Even when the ECU regulates the alternator it is still a regulator that is doing it and the regulation could just as easily be done with an external regulator.

Originally Posted by joeventura

So a single wire to the Alternator (shown here) does what you describe yes?

The number of wires doesn't matter. A GM 1-wire alternator has a regulator inside. Alternators are too easy to regulate to not have a regulator.

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