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mains current [amps]reading

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pageshiner

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Jan 9, 2004, 1:15:05 PM1/9/04
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who's in charge here,how do I take a current reading from the mains
without blowing up my meter,remember we are 240v rms,13 amp over
here.Ive tried once and now one of my test probes looks like I have
been welding with it,I had the meter set to amps a/c not milli or
micro and put the black probe to the neutral and the red to the live
and nothing happened think I caught the earth on the way out and it
went with a bang,thats as far as I got.

scada

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Jan 9, 2004, 4:56:56 PM1/9/04
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"pageshiner" <pages...@fsmail.net> wrote in message
news:b81fb7d.04010...@posting.google.com...

Your lucky your here to talk about it! Current measurements are taken with
the metering in SERIES with the load. Never across (Parallel) to the load,
that puts a direct short on the main! in your case, you can not put your
meter in series with the main either! You need a "Clamp on" ammeter. Such a
meter has a squeez handle that allows its Jaws to go around one conductor.
The reading is read on the meter through induction. If you are not certain
of what you are doing, Don't Do It! You will only hurt yourself, or others!


JeffM

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Jan 9, 2004, 6:30:49 PM1/9/04
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>...how do I take a current reading from the mains

>without blowing up my meter
>...one of my test probes looks like I have been welding with it
>pageshiner

Disconnect wire from output of circuit breaker
. /
Main +----+ / wire to outlet
------| |--+ ------
| CB | | |
| | | | Connect Ammeter between breaker outut and wire to
outlet.
+----+ | |
| |
+--------+
| Meter |
| |
+--------+
All the current must pass THRU the meter.

A much better way to do this is with an amp-clamp.
http://images.google.com/images?num=100&hl=en&lr=lang_en&ie=UTF-8&oe=UTF-8&safe=off&q=amp-clamp&sa=N&tab=wi
http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=amp-clamp&btnG=Google+Search

My question is, "How have you managed not to kill yourself so far?".

Ken Taylor

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Jan 10, 2004, 12:00:36 AM1/10/04
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"pageshiner" <pages...@fsmail.net> wrote in message
news:b81fb7d.04010...@posting.google.com...

Power in UK is 240VAC, but the current is determined by the load. You
measure current in series with the load, not by putting your leads across
the mains. You've probably blown up the meter too. Get an electrician to
measure it for you if it's important.

Ken

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