Why? If the source has a low resistance/impedance then you're ok as soon as
you have good probe contact. If not, then you could always twist the probe
leads together a bit to try to make a balanced line to cancel induced noise.
Crude, but it would help if the signal to be read was DC or audio AC.
That is certainly true (though perhaps your heirs are the ones who
will find you), but doesn't modify my statement. In this case, the
tool *can* be used as long as the one using it knows what he's
Ok....everything seems to pass right over your head....
I pointed out a limitation of a DMM and you seem to be inferring that I
am somehow a hack who blames his tools...
BTW> I am not a "craftsman" I am an electrcian..
You don't do what I do for as many years as I have without knowing what
the fuck you are doing.
It's not the right tool for the job.
A meter which gives you a false reading with bad (or no) contact is a
BAD idea in dangerous high voltage/high energy circuits.
That is why proper meters with low impedance (Kohms) modes exist for
the job, e.g. Fluke 113, 110 series, 289 etc.
The circuits are loaded, so any bad contacts will certainly affect the
reading. Which is the way I like it. Any funny readings, move up to
the next point in the line and check there.
I do know better than to measure an unloaded line without sticking
some suitable load across it.
Anyways, AIUI, this started with a meter with Hi-Z in the mV range,
most DVMs use a 10M or 1M divider at higher ranges.
For an electrician who know nothing about electricity (99.44% of
them, apparently), or if that's all one is ever going to do with
the meter, perhaps. For anyone who knows anything about
electricity or wants a tool that has more than one use, the high
impedance meter is a better choice.
I would agree. Take two meters. One is 1Kohms. The other is 1Gohms. If
the load is low impedance, say 100 ohms, then there's an appreciable
error with the low impedance meter-- simple ohms law. While the error
associate with the high impedance meter is unmeasurable.
People are probably confusing the fact that a high impedance meter
while unconnected to anything will pick up signals, for obvious
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