When does a car battery get used?

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void.no.spam.com@gmail.com - 01 Apr 2008 17:59 GMT

The car battery is used when you turn on the ignition. The car
battery is also used if you turn on any lights, or the radio, while
the engine is off.

But what about when the engine is on? Does the battery get used at
all? You can drive for hours with the headlights on, and that doesn't
seem to drain the battery at all.

I want to get one of those air compressors for my tires, which use a
cigarette lighter plug. Just want to make sure that if I'm inflating
my tires while the engine is on, that it won't drain my battery.

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Speeders & Drunk Drivers are MURDERERS - 01 Apr 2008 18:26 GMT

On Apr 1, 10:59 am, "void.no.spam....@gmail.com"
<void.no.spam....@gmail.com> wrote:

> The car battery is used when you turn on the ignition. The car
> battery is also used if you turn on any lights, or the radio, while
[quoted text clipped - 7 lines]
> cigarette lighter plug. Just want to make sure that if I'm inflating
> my tires while the engine is on, that it won't drain my battery.

They got this new thing out. Called an alternator.

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Larry Bud - 01 Apr 2008 18:48 GMT

> > I want to get one of those air compressors for my tires, which use a
> > cigarette lighter plug. Just want to make sure that if I'm inflating
> > my tires while the engine is on, that it won't drain my battery.
>
> They got this new thing out. Called an alternator.

Does your piece of sh.t have a working alternator? I figured someone
like you just leeched off of others, needing a jump wherever he went.

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John A. Weeks III - 01 Apr 2008 19:55 GMT

In article
<95dec1d1-f322-47b6-bbd0-c0c99280545f@d1g2000hsg.googlegroups.com>,

The battery is used all the time. It is running in one of three
modes, either charging (more current flowing into the battery
than what is being used by the car), discharging (more current
being used by the car than what is flowing in from the
alternator), or capacitor mode (where the battery is used
to smooth out voltage and current spikes).

The real question what is the current draw of your compressor,
and what is the duty-cycle. For example, if the compressor
pulls 40 amps and runs 100% of the time, you probably will
end up with a depleted battery. But if it runs only 15% of
the time, the battery has 85% of the time to recharge and
recover. If the compressor draws only 4 amps, that is
harly enough to make a dent in the battery's capacity, so
it doesn't matter what the duty cycle is in that case.

The formula is to take out less power over time than what
the alternator can replace after taking care of the needs
of the accessories in the car.

-john-

Signature

======================================================================
John A. Weeks III 612-720-2854 john@johnweeks.com
Newave Communications http://www.johnweeks.com
======================================================================

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Jim Yanik - 01 Apr 2008 20:26 GMT

"John A. Weeks III" <john@johnweeks.com> wrote in news:john-
8F9EFF.13553001042008@sn-radius.vsrv-sjc.supernews.net:

> In article
><95dec1d1-f322-47b6-bbd0-c0c99280545f@d1g2000hsg.googlegroups.com>,
[quoted text clipped - 32 lines]
>
> -john-

FYI,I bought a Master Flow MF-1040 12v 150PSI high volume compressor from
PepBoys,and I'm very satisfied with it. It cost me $21 after a sale and
rebate coupon. It's a much better 12v compressor than the usual inexpensive
auto compressors. It's not nearly as noisy as the others.It's fused for 15
amps,but runs fine on my car's 10A cig lighter.

My only complaint is that my car only energizes the cig lighter when it's
running.I have an adapter to use it directly on the battery terminals,and
after topping off all 4 tires,it has no noticable effect on the battery
when starting the car.

Harbor Freight sells one identical to it for less than $20.

Signature

Jim Yanik
jyanik
at
kua.net

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Studemania - 01 Apr 2008 21:18 GMT

> "John A. Weeks III" <j...@johnweeks.com> wrote in news:john-
> 8F9EFF.13553001042...@sn-radius.vsrv-sjc.supernews.net:
[quoted text clipped - 57 lines]
>
> - Show quoted text -

This whole thing seems a bit silly.
It takes about five minutes time with the compresser using 4 amps for
only a small part of this time to do your tires.
The starter takes about 100 amps to turn an engine.
If you can start your car on a cold day, you can fill your tires.
What is the amp-hour rating of your battery?
What is the number of amps used when the pump is running?
How long does the compressor run under load? Work out the math and
your face will be red from having asked this question.
(Had you asked the salesperson or manufacturer, you would have felt
silly in the eyes of only one person.)

I know, I'm mean. I should be easier - I was ten years old once.

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