Just WHAT are you smoking? (archive)

If you connect a 12 volt bulb in series with the battery connector. You are connecting a lighting device meant to hold maybe 1/2 amp to a 200 amp circuit for God's sake!!

The bulb will explode possibly burning poor matt if he has the bulb in his hand, or showering him with hot glass, blinding him at the very least.

You must use an professional ampmeter capable of withstanding at LEAST 200 amps for such a test. Using anything different will destroy the starter and chance serious personal injury to the user. The battery can supply 1000 amps short circuit current, so you really should use a 1000 amp ampmeter to be safe.

If you don't understand these things PLEASE leve them to those of us who do.

Don

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Don,

With all due respect, it is you who are in the dark.

Although a car battery IS capable of supplying 1000 amps, it can only do so when presented with a load (resistance) capable of doing so. We are talking dead-short here.

A bulb cannot possibly draw much more than its rated wattage without harmlessly simply burning itself out. When put in series with the battery connector as I advised, with all electrical equipment off, it won't draw anything unless some car accessory is "on" when it should be off.

In that case, the most the bulb can "see" is 12 volts, which, after all, is what it is designed to run on! There is absolutely no way that a tail light bulb can draw more than about 5 watts, or less than 0.5amp from a 12 volt battery.

No exploding bulbs, no flying melted glass blinding innocent children, period.

Lets face it, if you had a meter capable of reading 1000 amps, and you were attempting to find a battery drain of one amp, how would you ever expect to read 1amp on a meter scale that compressed 1000 amps into a 90 degree scale??

I hold a degree in physics, and spent 2 years working as a nuclear and electronics engineer for an R&D lab before my present career. While a lot of things have changed since the 1970s when I was working in the field, I can tell you that these laws of physics have not: Current(amps)=Voltage/Resistance and Power (in watts)=Volts X Current.

Bob

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