Water Cooled 190-Ampere Alternator

IS THAT WHY
I can throw a blanket over a 15 amp electric 120vac heater and not have it catch fire?

Yet wrap a 120 amp cable from an alternator and have it instantly ignite?

Alternator running at double the voltage, same power in watts, has half the current flowing through it. Half the current leads to one-fourth heat produced by loss due to resistance in the internal coils. It's probably not that simplistic because the coil resistance would change, but even if it doubled, the heat generated would still be cut in half.

When doing power upgrades for performance cruisers (retired racing sloops), I have installed more than a few Balmar alternators with ratings like 200+ amps at 12V. These are still fan cooled units.

Higher system voltage will make little difference. Electric machines are all about Watts.

Many years ago, I had to do a repair on a GM diesel buss engine that was leaking oil from the alternator. Yes, it was an oil cooled alternator. That was no stranger than the temperature controlled oil coupling for the cooling fan.

Matt

The sooner we switch to higher voltage systems the better.

Must be bad air flow if the alternator requires water cooling !

It's for an Audi and they like to make things complicated just for the sake of it. I have one with a liquid cooled alternator and it doesn't look airflow restricted at all. Perhaps it's to get the cooling fan off the alternator to get a 0.01 mpg increase. Other examples of complication are my battery is under the driver seat, and the battery management module has to be reset with a proprietary scan tool when replacing the battery.

Common for stators to run at 320°F and rectifiers at 280°F
Oil cooled alternators run at 210°F constantly. Keep an alternator cool and it will not lose 20% of its potential.
This one could run constantly at full output.

Engine coolant temps can reach 250F these days (anti-freeze raise the boiling point; so does pressure in the cooling system).

Must be bad air flow if the alternator requires water cooling !

time2roll wrote:
Where does an RV get chilled water?

Normal engine coolant is all it needs.

Sam

theoldwizard1 wrote:
Why ?

^Im with this guy.
What’s the point? An A8 is a mid engine sports car that for some reason needs not only a high power alternator but it needs to be water cooled.

There is a wheel here that doesn’t need re-invented for RVs.

Where does an RV get chilled water?