In article ,
dave L wrote:
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.

That would be a shunt for measuring current using a sensitive meter - you
'shunt' the majority of the current across the resistor and the meter
reads the rest in proportion. These sort of shunts will be fitted to the
amps range of any meter, but are rather specialised to make since the
ohmic value can be extremely low and needs to be accurate. They're often
simply a strip of metal.

However, for increasing the current drawn while measuring mains, you need
wire the resistor in parallel with the meter in the same way, but of
course for measuring voltage the combination is wired in parallel with the
mains rather than in series as for current measurement.

If you want to experiment, I'd use a 22000 ohm (22k0) 3 watt resistor from
Maplin (W22K) at 0.37 gbp. This will draw about 10 milliamps and is within
its 3 watt rating.

Obviously, there are safety implications since you'll be measuring mains,
so don't attempt this if you're unsure about how to do it safely. I'd buy
a second set of test leads and incorporate it into these, enclosing it in
a box suitable for the fact that it will also get quite hot with prolonged
use.

--
*Horn broken. - Watch for finger.

Dave Plowman London SW 12
RIP Acorn