Testing Lightswitches with Multimeter

diable

If you want to test the switch then disconnect it from the wire ( go through all the posts on here how careful you have to be and to insulate your screwdriver with your grannies knickers etc etc )

If you multi meter has a tone test/through test which just makes a noise when the circuit is activated then you can test your switch as the contacts sometimes fail. Me personally I'd just disconnect the switch and put the two wires together to test the circuit.



(disclaimer if anyone on this forum has read any of my threads/post and have died from a result of them then it is though their own stupidity and if any accusations are made towards me then I will seek justice through the courts) ;o))))))

muckybutt

As others have said before, a multi meter is way way beyond your capabilities if you are asking how to use it.

I imagine your sparky chap was meaning a multi function tester rather than a multi meter, the tester indicates voltage as soon as you place the probes on L - N, L - Earth or N - Earth. It will also indicate a switch working correctly by using a continuity function.

Personally I would also use a volt stick as a first port of call for testing for live backed up by a decent set of testers.

http://metersandtools.com/Fluke-T-Electrical-Tester/M/B000VRJGUM.htm?traffic_src=GB&utm_medium=CSE&utm_source=GB&id=uk other makes available !

Leif

Ebe_Scrooge wrote: »

Eerrrm - with respect, if you're not sure how to use it, I would say the safer option would be to simply switch off at the mains before you start fiddling about. Not meaning to be discourteous, but you really don't want to be chancing your arm with 240v if you don't really know what you're doing.

The OP said "I just want to use the multimeter to test that the switch is dead" which suggests that he has indeed turned off the power at the switch box. Otherwise it is nice to see that you have posted a polite message unlike some here.

I'm not sure I like the discourteous and mocking tone of many other posts in this thread, there is no need for such rudeness. It is quite easy to warn someone that something is potentially lethal without being patronising or rude. And I think the OP realises that there is danger which is why he is asking for advice. Then again the faceless nature of the internet does sometimes encourage group unpleasantness.

My concern would be that a cheap probably made in China multimeter might be unreliable, and give inaccurate readings even after it has been tested and found to work in that one instance.

Another worry might be that someone else in the house might find sockets don't work, then flip the circuit breaker without the OP knowing until it is too late. :A (I have no idea what the angel symbol means but perhaps it is appropriate here.)

ormus

my main use for a multimeter is to use it as a continuity tester, not as a 240v voltmeter.
switch off the mains at the consumer unit and then use the meter to test for for continuity on (dead/not live) problem wiring/circuits.
i very rarely use mine to test "live" 240v circuits.
and i use extreme care.

diable

ormus wrote: »

i very rarely use mine to test "live" 240v circuits.
and i use extreme care.

Unless I have one leg in a bucket water and the other touching a copper pipe........ you meant ;o))

vaio

OP:

The approved method is....

Check meter is working on a known to be live circuit or proving device
Switch off circuit to be isolated and check L-N, L-E & N-E
Check meter is working on a known to be live circuit or proving device

Also worth noting that multi meters & un-fused test leads are not generally approved for this sort of testing. I don't think there are any approved non contact devices so volt sticks are out too

In the real practical world, I use my meter for checking voltages every day but it is a £200 fluke that gets used every day. If it was a £5 made in china job that got used twice a year I'd be less inclined to trust it

also, multi meters are high impedance so tend to show any induced voltages which can be confusing. Proper voltage testing devices are lower impedance so don't suffer from this problem.

diable

Just stick the two wires together if the light comes on it means the switch is fcuked.

1984ReturnsForReal_2

vaio wrote: »

OP:

The approved method is....

Check meter is working on a known to be live circuit or proving device
Switch off circuit to be isolated and check L-N, L-E & N-E
Check meter is working on a known to be live circuit or proving device

Also worth noting that multi meters & un-fused test leads are not generally approved for this sort of testing. I don't think there are any approved non contact devices so volt sticks are out too

In the real practical world, I use my meter for checking voltages every day but it is a £200 fluke that gets used every day. If it was a £5 made in china job that got used twice a year I'd be less inclined to trust it

also, multi meters are high impedance so tend to show any induced voltages which can be confusing. Proper voltage testing devices are lower impedance so don't suffer from this problem.

The approved method doesn't involve a multimeter because it is not an approved device.




Its not that they are not generally approved, they are not approved at all.

macman

Approved? That one certainly isn't. If it's a rebranded Micromark, I've had two. One lasted a month. It's warranty replacement lasted a week.

vaio

1984ReturnsForReal wrote: »

The approved method doesn't involve a multimeter because it is not an approved device.




Its not that they are not generally approved, they are not approved at all.

It's tricky, GS38 says multimeters are non preferred, not not approved

Fluke say my meter is IEC 1010 cat 4 and so safe to use at the transformer end of the LV network

In practice my fluke gets used most days, the martindale lives in the test instrument case and gets used once a year when the NICEIC man comes calling