Battery cable came off!

The battery does as Jim said. But another condition called load dump
could have created a destructive transient. Load dump is defined by
the ISO to be as large as 270 volts on the 12 volt system. SGS
Thompson defines it as 80 to 100 volts. But then better automobiles
are designed with electronics that make load dump not destructive.

Of course when you connect a computer to the car using a discount
inverter, does it have load dump protection - or did you just save some
pennies?

The damage, if it occurred, would be complete in milliseconds.
Apparently you did not suffer load dump damage. But you, like many
others who replied here, should know of load dump and what automotive
electronics (properly constructed) cost more money.

 

Fair enough - a SIGNIFICANT spike.

And pray, how does it do that? It's not a voltage regulator, it's not a
capacitor. Internal resistance limits how quickly it can react to voltage
changes.

You mean the battery cables? Yeah, that'll fry your alternator in a hurry,
since you're basically shorting its output.

I wouldn't even try it in a '76.

See the phrase "IN THE FIRST PLACE" in my above paragraph.

Of the four uses Darden lists for the battery, I've already noted the first and
fourth above... for the second ("filter and stabilize") it can only do so much -
there's still ripple in the voltage measured even with the battery, as the
charging voltage is usually well above the battery's voltage... as for the
third, if the battery is really needing to "provide extra power" while running,
then the charging system is under-rated to begin with, and the battery is acting
as a band-aid.

 

Fair enough - a SIGNIFICANT spike.

And pray, how does it do that? It's not a voltage regulator, it's not a
capacitor. Internal resistance limits how quickly it can react to voltage
changes.

You mean the battery cables? Yeah, that'll fry your alternator in a hurry,
since you're basically shorting its output.

I wouldn't even try it in a '76.

See the phrase "IN THE FIRST PLACE" in my above paragraph.

Of the four uses Darden lists for the battery, I've already noted the first and
fourth above... for the second ("filter and stabilize") it can only do so much -
there's still ripple in the voltage measured even with the battery, as the
charging voltage is usually well above the battery's voltage... as for the
third, if the battery is really needing to "provide extra power" while running,
then the charging system is under-rated to begin with, and the battery is acting
as a band-aid.

 

Uh, the battery is nothing more thann a large capacitor. Capacitors are
the main components of voltage "smoothing." You know, like radio noise
suppression etc.

JT

 

Uh, the battery is nothing more thann a large capacitor. Capacitors are
the main components of voltage "smoothing." You know, like radio noise
suppression etc.

JT

 

Actually, they're not. Capacitors /store/ electrical energy. Batteries
/create/ it via a chemical reaction. Charging a battery is not storing energy;
it's (to oversimplify) merely reversing the checmical reaction.

 

Actually, they're not. Capacitors /store/ electrical energy. Batteries
/create/ it via a chemical reaction. Charging a battery is not storing energy;
it's (to oversimplify) merely reversing the checmical reaction.

 

Technically yes, but both smooth voltage..

JT

 

Technically yes, but both smooth voltage..

JT

 

Batteries do, to a degree. That's not what they're designed for though.

 

Batteries do, to a degree. That's not what they're designed for though.

 

But it's one of the things they're *used* for.

Do you want to email Bill Darden and tell him he's wrong?

 

But it's one of the things they're *used* for.

Do you want to email Bill Darden and tell him he's wrong?

 

Batteries most definitely do have capacitance, do you have a meter?

Batteries most definitely do store energy when charged. Or are you
suggesting that when it is used up that more is created out of nothing?

 

Batteries most definitely do have capacitance, do you have a meter?

Batteries most definitely do store energy when charged. Or are you
suggesting that when it is used up that more is created out of nothing?

 

The plates of a battery have capacitance.
They are charged by the chemical reaction.

 

The plates of a battery have capacitance.
They are charged by the chemical reaction.

 

Capacitors are electrostatic while batteries are electrochemical.
A capacitor capable of storing the energy within a car battery and power
capability needed to start a car would be the size of a double long semi.

 

Capacitors are electrostatic while batteries are electrochemical.
A capacitor capable of storing the energy within a car battery and power
capability needed to start a car would be the size of a double long semi.

 

True, but nobody is suggesting that you start your car with a capacitor. At
issue was the batteries ability to absorb spikes from the alternator. Given
that, batteries do have capacitance. I don't know how much it should be to
be effective though, but its there.