DIY Doctor UK DIY Forums

I am looking to upgrade an inline timer fan for a more powerful unit, again with an override option on it.
Also in the bathroom are 2 led ip65 jcc v50 downlights. A pullswitch operates the fan and lights along with a 3 pole fan isolator switch outside of the bathroom. A ceiling pir was installed previously and this is what I found behind it.
I would like to connect everything back up to a new pir sensor in keeping with the original plan but no sleeving was used previously and it looks like live switch feed from the fan is being used a grey conductor into the live switch feed from the pullswitch I'm blue but without brown sleeving. Would I be correct in thinking that a lighting feed as a brown conductor in the same terminal would be for the switch live for pir?

You will need a safe means of testing to establish what does what, since it is up to the person who wired it what colours they chose to use.

(For what it's worth, you are not the first and will not be the last to ask this type of question.)

Thank you for your response.
Am I correct in thinking that a continuity test would need to be performed for each cable to establish what does what? I do have a multimeter.

Multi meters are best suited to electronics. Also, the average multi meter is not designed to be used on mains, they often have a range up to 600v ac, but are known to explode if you get it wrong, mains electricity is very unforgiving, a proper two probe mains indicator is much safer and is designed for the job.

@Mr white is right, I have used a multi-meter for years, but moved the the clamp-on type as it does not have a wired amp range, so can't make an error that causes a direct short. Mine also has a non contact volts range. [attachment=0]Clamp-meter-small.jpg[/attachment] this shows my old yellow and new red one, the new one will measure DC and AC amps down to 0.001 amp so good for testing earth leakage. Old one AC amps only and down to 0.01 amp but does have Hz range.

You can do the job with a standard multi meter, but I went back to do my 'A' levels, and was in a class where out of the 16 students 6 managed to blow the fuse in the multi meter by selecting the wrong range.

However the volt tester used to test for dead, so no battery or dial so one can't select wrong range, should also have a proving unit to show it works, they don't have any ability to do continuity they have no ohms range or diode check or buzzer, and I would hope you would test with power off? So with power off your multi meter will be fine.