My Magnets are Hot !!

[Windwalker]

I have seen many posts about power supply and alternator output. Stock systems and more. People say they run big boxes on stock with extra batteries. ETC.
Well lets take alternators.
Now !
The engineers that design cars don't give you much more than you need. The capacity of the charging system is within certain tolerances over time. The principals of an alternator charging system vary greatly upon heat. Lets study that.
If you have a 100 amp alternator as factory equip, doing the 12 volt system duty. What happens when it gets hot from running an 8 pill. The magnetic field inside the alternator is weakened. Electricity is lost at the source.
Now understanding that amps times ohms equals volts ( OHMS LAW ) what happens when the heat drops the voltage?? The amps go high which creates more heat and may cause an operator to have false readings in regards to amperage. Its a vicious circle. Everything holds a loss right down to the antenna. So having said that
You cant run an 8 pill or a big box off a plain alternator for long. You will have barely any key down time no matter how much you rev the engine.

WW!

[str8stroke]

agreed......but

There are a few variables in your hypothetical set up. Like pill types, vehicle types. a 2x6 (which equals 8 total pills, not 12 lmao) connected properly to a Heavy Duty system like those found in most diesel trucks with more than one High Performance battery can work quite well. All that is needed is a large line cap. I have installed a few of those and they work very well. Not ideal, but work fine for years. Devil is in the details.

['Doc]

Heat, as such, is seldom the cause of an alternator not being able to provide enough current to run something. The problem in such instances is that the alternator is unable to provide the required current to start with, it's being asked to do something it was never designed to do. By the time heat affects the windings or magnets enough to cause a voltage drop that alternator has already reached and is well beyond it's limits. That alternator supplies all of a vehicle's electrical needs, the battery only comes into play when starting the engine and supplying the excess draws for short periods of time. That battery also puts a draw on the alternator when it's recharging. When the total draw reaches the point where the alternator can no longer supply enough current then everything in the system get's less than is required. That typically means that the battery starts going dead because it's supplying the excess draw. That's more common than you might believe, and as long as the draw lessens so that the battery is recharged, it isn't apparent that there's a lack in the ability of the alternator. That lack of ability, or capacity of producing current, isn't because of it's component parts getting too hot. It's cause is lack of judgement in evaluating the size of alternator needed to produce the total current required.
If this lack of 'ability' is because of adding an amplifier to the mix then it's a very safe bet that the required current draw of that amplifier is greater than is believed, which is also very common...
- 'Doc

[Ohio_359]

Very well said Doc

[Windwalker]

Well there are many good points here. I guess I personally like to reduce the heat all over. Since I feel that an alt runs better cooler.
Yes pill size matters and I was thinking about 8 2879s.
There are a million ways to cause electrical loss, Using the principals behind Ohms Law just make sense to me.

WW1