help identify load/ring in a fused isolation switch

[Lusi83]

Just had a new kitchen fitted - including a complete kitchen rewire...
Got my brother (a newly qualified electrician) and the guy he works for (very experienced) to do the electrics - only problem is they came 300 miles to do it for me and did the first and second fixes together. (Even including a hotel and petrol -it was still £400 cheaper than I was quoted and I am sure they did a good job and also added a few extras).
My kitchen fitter agreed to this (he told me his electrician's quote seemed high!) but then kept making remarks about not trusting the electrics of someone he doesn't know....(otherwise the fitters seem to have done a really thorough job). They had to loosen the socket covers and remove the covers of the isolation switches completely to the fridge/freexer, washing machine etc to tile behind.
I agreed to screw the covers back on...(I have replaced light switch/socket covers in the past) and re-attach the isolation sockets.
Only problem is they didn't twist the wires together...on some of them I can tell which are the likely ring/socket wires -but especially on one it is impossible to tell.
I did ask my brother on the phone but he managed to confuse me (talking about multimeters etc) and I think he is a bit p*****d off - I have phoned him several times cos the fitter was complaining about silly stuff.
Can anyone give me a simple way of working it out and written down I will find it easier to follow...I did buy a cheap multimeter and also noticed that B&Q sell something that you plug in and it tells you if your socket is wired correctly...is it worth having?
I should say the kitchen ring is on a separate circuit and I had a new consumer unit fitted...I have been led to believe if I get it wrong the worse thing that could happen is the circuit will trip....
My brother will be coming back to certify it but not a month or so - so I have no electrics in my kitchen and the fridge etc are on extension leads...
Alternatively I could get someone in to do it...

 

[ElectricDunc]

Simple way of doing it is to make sure the circuit is switched off and safe to work on. Get your multi meter out and put it on the continuity setting (low ohms). I assume you have 3 cables there so pull forward the socket that the appliance is plugged in to (the one fed from the load side of the FCU) and test between the live of that socket and between each of the 3 live wires going to the FCU. Only one cable will give you a positive reading and that will be the cable that goes to the load side of the FCU.

 

[Steve]

The item you're having trouble with seems to be isolation switches, on the ring main.

You'll have three cables. In order to verify ring continuity between 2 of the cables, you need to:

1. isolate power
2. take your three live wires - the brown ones.
3. turn on your multimeter and set it to audible continuity. Might have a picture of a musical note or something. If not, set it to a low ohms resistance scale.
4. probe the 3 wires in turn and when you get to the ones that beep, you've found your ring!
5. If you like, for peace of mind, probe the corresponding neutrals and earths for those two cores.

 

[Lusi83]

Thanks for the help - I think I have it worked out but I think I did it the way my brother was trying to tell me....although it took me a while to realise I had to take the plastic bit off the battery in the new multimeter before it would work.... And if this is totally wrong please let me know...

First ElectricDunc ...my multimeter won't reach between the socket and the FCU - especially the tricky one...socket is under a window close to a sink so the FCU is a meter or so away...

And Steve - your way didn't seem to work - possibly because I have four isolation covers off so the circuit isn't anywhere near complete...

The way I did it was to connect the multimeter to the live and neutral in the socket ...and then touch the live and neutral in each of the cables feeding the FCU together -until I got a reading (or rather an almost zero)...and this should be the load cable -unless I am being stupid (which I could be considering how long it too me to get the multimeter working )
Hopefully I'm right thinking at worse it would trip the switch....

 

[Zambezi]

Sounds like you have cracked it.
If you want to be able to reach the FCU to try the other ways suggested then you can connect a piece of cable between one of the probes on the meter and connect the other end of the cable to the cable you are trying to reach (make sure you disconnect it before turning anything on!).

 

[Lusi83]

Thanks for the all the help....and at least no-one has said if you get this wrong the house will fall down...

Haven't finished doing them all -so haven't powered up yet - so don't know if it is going to go bang or not.....

But worked out an even easier way of identifing the load circuit - at least on the ones the socket and FCU are close together ...wriggle the cable in the socket and see which cable moves in the FCU... so far this agrees with the multimeter...
At the very least it is an extra reasurrance...