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I'm having some problems with battery going dead sometimes, and I noticed that there are some small sparks after disconnecting the battery for a few seconds and then reconnecting again. It is not big current (I have to go check with multimeter but I think that it is no more than 500mA, and only initially, it is reduced later).

If everything is turned of, then how big current is to be expected for clock (analogue, car is produced in year 1990) and alarm, which would not be considered as parasitic drain? I'm thinking that anything more than 25mA should be considered an issue?

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It varies with different cars 50-75 ma is usually acceptable, the initial spike you see is normal. It's from everything powering up initially.

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What should be car's autonomy time? If 50mA is normal, then good, moderately charged battery with 50Ah will hold 1000 hours of 50mA drain, which translates to ~40 days. So with 50mA, if you have not so good battery, you have to drive your car at least twice a month... – Goran Obradovic Sep 5 '12 at 13:21

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