bad earth maybe?

[theo]

My Alpine stereo draws about 30 milliamps. It's a plain jane model. I have a clock that draws about 15 I think. I'm not sure if 200 is too high.

If your battery is rated at, for example, 40 Amp-hours, that's 40,000 mA-h. So you could draw 40,000 mA for an hour or 1 mA for 40,000 hours or 200 mA for 200 hours before the battery was dead. Doesn't seem like very long - a little over 8 days.

According to that 200 mA is too much. I was wrong once though.

 

[Pin_Head]

An average auto battery is about 600 amp hours. At 200 mA, it would take 1500 hours (60 days) to drain it by 50%.

 

[theo]

I think you're confusing amp-hours with CCA (cold cranking amps). For example, the Optima red top is rated at 120 minutes RC (reserve capacity). That means it can provide 25 amps at 80 degrees F for 2 hours without dropping below 10.5 volts. That makes it a 50 Amp-hour battery.

The red top is also rated at 800 CCA. In the US, CCA is the number of amps the battery can supply at 0 degrees F for 30 seconds without dropping below 7.2 volts. The Brits and the rest of the world have higher standards for CCA ratings.

But goshdammit, I still don't know if bad's 200 mA is too high.

 

[miletwo]

I've never heard of the coke thing for cleaning battery terminals. I usually mix baking soda in some warm water and splash that on. The base pH of the baking soda counters the acid on the terminals neutralizing the acids and washing it all away. No sugary mess required.

Works for me.

 

[largenfirm]

I've never heard of the coke thing for cleaning battery terminals. I usually mix baking soda in some warm water and splash that on. The base pH of the baking soda counters the acid on the terminals neutralizing the acids and washing it all away. No sugary mess required.

Works for me.

Well, that's fine, except that what's on the terminals isn't acid - it's what happens after tha acid eats the terminals, and its pH is basic, not acidic.

The coca-cola thing is ancient - my Grandfather used it on his cars before 1940.

FWIW.

Kirk

 

[Pin_Head]

I think you're confusing amp-hours with CCA (cold cranking amps).
But goshdammit, I still don't know if bad's 200 mA is too high.

Oops, you are right: I got the decimal point wrong. They are 60 amp hours, not 600. It would take about 6 days to drain it by 50%.

200 mA is on the high side, but this current is apparently not constant.

 

[bad_religion_au]

it goes dead randomly, will be fine for weeks. some audio guys recon 200 is too high, but i can't figger what is causing the high reading

 

[largenfirm]

it goes dead randomly, will be fine for weeks. some audio guys recon 200 is too high, but i can't figger what is causing the high reading

I have a bad feeling about that player...

How about disconnecting it for a month or two, or putting it on a switched circuit, and seeing if the problem persists?

Kirk

 

[bad_religion_au]

it wouldn't help that the alternator isn't charging enough to supply at heavy voltage load doh:

 

[Jman]

Bwa ha ha.

Does the voltage regulator work?

 

[bad_religion_au]

don't know.. . how do you tell/ test? wiring isn't my strong point... only got a multimeter the other day