Please help! Electrical advice

[digitalfm]

Hi, I'm building a cinema room and have just fitted new lights.

In the light fitting I have the usual 1 black 'live' wire and two black 'neutral' wires twisted together in the same terminal. See below.



When disconnecting the two neutral wires from the light itself they pinged apart so then I couldn't tell which black wires were the original neutral pair and which was the single 'live'.

I paired up the two neutral wires that I thought went together, and connected it back up to the new light and it all works fine, but i'm concerned that I may have paired up one of the old neutral wires with the live, and put the other neutral wire in the live terminal of the light.

My question is, would I know if i've connected the wrong two black wires to the neutral terminal? ie, would the RCD pop or would the light simply not work? Is there any way to test the wires are connected correctly.

Your help's appreciated.

P.S. please excuse the spelling in the title :-)

[nokityet]

hello digitalfm, it sounds as though you have been lucky in selecting the right cable as the switched live, becuase if you had crossed a nuetral with a switched live when you came to swith the light on at the wall the mcb/fuse would have blown.without the relevant testers to identify the cables you could switch the light on at the wall, then turn off the power to the lights at the fuseboard. dissconnect the black wire from the wall switch (making sure that its not touching anything) and then turn on the power, if it is the switched live then the light in the cinema room will not work yet all the other lights in the house will as this is a 'loop in' system of wiring. When you are satisfied that all the lights work as they should, turn off the power again and reconnect the black wire into the switch. happy days.

[LV426]

Not really a custom installation; more a DIY question, I think. Moving >>>>>

(PS I've corrected the spelling).

[avanzato]

I mark the switched live cable with red electrical tape. So that.

A: You know which is the switched cable

and

B: A future electrician/DIYer knows it's not a neutral connection but is 'live'.