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OH dear, Manolo. I am so sorry to have my message interpreted as maligning your own abilities forcing you to defend your alma mater. The piece of my post you chose to quote implies another context, but it did not refer to you.
What I read of your method was indeed common practice in the days when automotive electrical systems made no (zero) use of the battery when shut off, and every mechanic's meter was an analog 20,000 ohms per volt VOM. This is where/when the expression "6 volt draw" was heard, to describe what would have been a 20 microamp drain. You didn't use the term, but your suggestion to use a voltmeter to measure current brought that old misnomer to mind.
Those days are long gone, as you would know measuring the normal current in the subject 89 240 if you had one. Todays meters can range anywhere from 1000 ohms per volt to 10 megohms input impedance. If you tell someone to measure a drain using a voltmeter, the results as conveyed to someone in New Jersey, Melbourne, or Kuala Lumpur are vague by possibly five orders of magnitude.
Yes, a lot of meter fuses get wiped out, so that's why the boss probably told you to use the voltage scale on his VOM, when he showed you that old technique. But most DVMs will have at least a 2 Amp scale and separate probe socket for it. A test light is immune from those errors, but neither method is of any use without some practice or training.
Again, my only intention was to support Chuck's valid method of looking for a drain, contradicting your criticism of that, not to malign yourself or your education.
Borg Sorenson Jr.
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