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dave L
 
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Default should unswitched live should as live on a neon screwdriver?

mike ring wrote in message . 252.50...

A good oldfashioned meter with a needle is prolly better to work with, or
as Dave said, try a shunt resistor across a DVM.

(sometimes I think they're more trouble than they are worth, it's truee
they will detect a .1 volt change, or check your battery to within about
a microvolt, but they can cause unnecessary alarm and despondency.

Can you explain how to use a shunt resistor in this context ? I've
had a search and most the hits are quite advanced enginnering or
electronics references.

However what I thought they meant was that I get a 0.1 ohm resistor
and wire it up between the live and neutral terminals of the pendant
and then measure the current that flows across the resistor. By my
maths (I=V/R = 240/0.1) this would measure (um) 2400A. I'm *know*
that's not what I want to do.

One post (http://tinyurl.com/v744) -which Dave Plowman contributed to
in '01- mentions adapting the multimeter. Is this the only way I can
use the stunt ? That's going too far for me, I think, as I want to
master (ahem) wiring before I get into electronics.

Whatever the method, if it does inolve measuring the current then I
need to head to Maplin as my multimeter doesn't measure AC current
(Gunson Pocketmeter2).

Thanks for your thoughts.