No, Greg. The entire CIRCUIT is at 13.8 volts. Not the battery. When you turn off the motor, the battery drops to 12 volts just like always. You really don't understand batteries. Just leave it at that. Otherwise you'll keep on making a fool of yourself.
-- Ray
You get a battery of credit cards.
-- Ray
Yes it is. It also provides stator winding current but never, ever will the battery be a 13.8 volt device.
See the above, Chuck. I realized I left out that important use but it is NOT for running all the accessories. When the alternator is running, the automotive voltage regulator (not to be confused with a real voltage regulator as used in electronics) isolates the battery from accessories in the car.
-- Ray
There's no such animal, Greg.
-- Ray
Impossible. Just not true.
LOL.
-- Ray
I don't have it in for you at all, Greg. I feel that there is a need for folk like you who are always wrong. Someday, you will suffer the fate of most Darwin Award winners and do yourself some real harm with all of your wacky notions.
A 12 volt battery will never be at a 13.8 volt potential. Can't happen. Not now or ever.
-- Ray
Ray Haddad skriver:
WHAT ????
Will yo then claim, that the whole eletronic circuit of the car is detached from the battery, when the car is running ?
Klaus
Probably with the engine running and the battery being charged.
But it is possible to observe if the light in the refrigerator does not go out, allthough indirectly.
We recently had one with a defect door so that the door contact was not activated, hence the light was on all time. This caused the temperature around the lamp to raise enough to make some food items go bad too early, whereas the overall temperature was still kept by the thermostatic control.
Not at all. Go back and read what I wrote.
-- Ray
Ray Haddad skriver:
Okay
I still read it as I understood it. Can you rephrase ?
Klaus
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I see that this topic is still CURRENT!
Bill
Sure.
When a car is started, the battery supplies voltage for turning over the engine and also to the stator coils on the alternator. It does this via the voltage regulator on a car, not to be confused with the kind of regulator we've been discussing on a DC power supply. Once the engine is running, the voltage regulator does other things.
In a car, when the alternator is supplying 13.8 volts, that is what is supplied to the lights, radio and so forth. The battery is a reserve power source, trickle charging merrily and supplying the stator voltage to the alternator. As long as the alternator is working, the battery is not being used for more than the stator windings. If the belt should break, as it has on a few occasions worldwide, the battery will power the car for a short while.
In a car, the voltage regulator keeps the current flow from the source of the highest capacity. That's another reason for the 13.8 volts of the charge circuit versus the 12 volts of a battery. As long as the charge voltage is adequate, the regulator uses that to power all the auto accessories and lights.
-- Ray
You mean it's forbidden to just push in the door switch plunger? Or slip oin one of those mini-camera cables SWAT outfits use?
On 12/24/2007 12:35 PM Steve Caple spake thus:
No, of course not, but you know about the Heisenberg Uncertainty Principle, right? The one that says that any attempt at measurement interferes with the phenomonon being measured? (At least that's my dumb-ass layman's take on it.) So how can you ever *really* be sure that the light is out when the door is closed?
Ray Haddad skriver:
And working as the filter capacitor in a normal powersupply.
It depends. Many older cars does not have high enough output from the alternator when the engine is at idle speed.
Yes, a few hours.
Klaus
It's a different kind of regulator. It's really misnamed. Normally they're mechanical relays inside of a sealed unit with the ability to switch high currents nearly instantly. They're nothing at all like regulators in power supplies. That regulator is normally built into the alternator inside the rectifier circuitry. In modern computerized autos, they're most often solid state switches.
-- Ray
Faith, me lad, sure an begorra, just believe!
Exactly Ray - geeze, it really takes a _long_ time for you to not understand the completely obvious!
Why do you keep stating that which is only correct when the battery is at 12 volts?
Even though I cited a manufacturer's data page on their lead acid batteries floating at up to 13.8 volts?
Yeah - well, what do the manufacturers know!?!
Regards, Greg.P.
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