Identifying live, neutral and earth in outdoor festoon lighting | on ElectriciansForums

Discuss Identifying live, neutral and earth in outdoor festoon lighting in the UK Electrical Forum area at ElectriciansForums.net

Richard Cook

-
DIY
Joined
Sep 19, 2017
Messages
59
Reaction score
8
Location
Sheffield
I bought some outdoor festoon lighting a few years ago and the 2 pin connectors (male and female) have corroded so I’m going to splice the connectors together using heat shrink butt connectors. Each run is 5m with a male and female 2 pin connector at each end. My first thought was that this would be a 2 min job but it turns out none of the wires are labeled so it’s tricky to work out which wires are live, neutral and earth once the connectors have been cut off.

See a few photos attached.

I can connect one end (thankfully the one end that isn’t damaged) to the “starter plug” which has a transformer (31v) so can voltage check each cable and plug it in.

At the other end, with the now exposed wires, what’s the best way to find the live, neutral and earth? I’ll then need to Wago, for testing, this to the other run but how do I work out which is live, neutral and earth on that run? Trial and error? What am I looking for? Would it trip the RCD until right? What about the transformer? Any way I can avoid breaking it with testing?
 

Attachments

  • [ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
    IMG_1243.jpeg
    1.1 MB · Views: 129
What is the writing on the transform? If it’s 31v, it might be DC, with a plus and minus rather than AC live and neutral. Unlikely to have an earth.

Is there any writing on the wires? There might be one that has a dotted white line to identify it.

Is the male and female plug and socket keyed? As in, can it only fit one way?
 
Also when plugged in the lights don’t light up. I’m thinking the three wires must loop back when they’re normally inside the male/female connector? If one side is connected to the plug then I thought they would light even though the other end has been cut off?
 
What is the writing on the transform? If it’s 31v, it might be DC, with a plus and minus rather than AC live and neutral. Unlikely to have an earth.

Is there any writing on the wires? There might be one that has a dotted white line to identify it.

Is the male and female plug and socket keyed? As in, can it only fit one way?

Thanks for the reply!

There’s nothing on the transformer. The writing seems like manufacturer stuff only. I’ve attached a bunch of photos. And yep it’s keyed.


[ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
[ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
[ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
[ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
 

Attachments

  • [ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
    IMG_1249.jpeg
    411.6 KB · Views: 66
  • [ElectriciansForums.net] Identifying live, neutral and earth in outdoor festoon lighting
    IMG_1251.jpeg
    1.1 MB · Views: 67
I don't see a transformer, so i don't know where you are getting the 31V from.
The label says 220-240V, so that's mains voltage.

Are the lamps removable? (unscrew)... if so, the centre pin will be live and the screwed outer will be neutral.... if you have something to measure continuity... If they are bayonet cap lamps, with the 2 pins... then it wont matter which way round the L and N are, as the lamp can go in either way.


Take extra care if these are mains voltage.... unplug before poking about in lampholders.
 
I don't see a transformer, so i don't know where you are getting the 31V from.
The label says 220-240V, so that's mains voltage.

Are the lamps removable? (unscrew)... if so, the centre pin will be live and the screwed outer will be neutral.... if you have something to measure continuity... If they are bayonet cap lamps, with the 2 pins... then it wont matter which way round the L and N are, as the lamp can go in either way.


Take extra care if these are mains voltage.... unplug before poking about in lampholders.

Thanks again.

I know what you mean but it has that big block on the starter plug (ConnectPro® 2m Starter Cable, Black or White - Powers up to 7600 LEDs - https://www.festive-lights.com/2m-starter-cable-with-uk-plug-black-or-white) but think I’ve been confused with ConnectGo vs ConnectPro (what I have).

The bulbs are all molded closed so that doesn’t help. I think if one light goes they all go if that helps understand the circuit.

If I plug in one end it should come on but it doesn’t… but if I multimeter each wire is there a reading I should be looking for for each one?
 
I bought some outdoor festoon lighting a few years ago and the 2 pin connectors (male and female) have corroded so I’m going to splice the connectors together using heat shrink butt connectors. Each run is 5m with a male and female 2 pin connector at each end. My first thought was that this would be a 2 min job but it turns out none of the wires are labeled so it’s tricky to work out which wires are live, neutral and earth once the connectors have been cut off.

See a few photos attached.

I can connect one end (thankfully the one end that isn’t damaged) to the “starter plug” which has a transformer (31v) so can voltage check each cable and plug it in.

At the other end, with the now exposed wires, what’s the best way to find the live, neutral and earth? I’ll then need to Wago, for testing, this to the other run but how do I work out which is live, neutral and earth on that run? Trial and error? What am I looking for? Would it trip the RCD until right? What about the transformer? Any way I can avoid breaking it with testing?
you use a multi meter or ohm meter and do a continuity test on the 3 conductors.
 
Only reason I can think of for the 3rd wire is to keep the other lights if one goes. Like the posh Christmas lights from 20+ years ago. My own festoon lights are 230v that have a similar connector. Unless you have crocodile clips to do it hands free, I really wouldn't recommend trying to measure the voltage by hand incase it is 230v.

Best doing resistance by clipping onto one of the plug pins and then tapping out the other end. If you get a low reading on one of them, that will be connected to the pin your clipped onto.

Look at that black box at the start of the run and see if it has an input and output voltage stamped into it.
 
Only reason I can think of for the 3rd wire is to keep the other lights if one goes.
I spoke to customer service and yes you cannot replace the bulbs but if one bulb goes it doesn't break the sequence (unless the bulb connection itself breaks) so I'm curious.

They also said "The wires are positive and negative wires which make up the AC-DC" which doesn't help me.
 
Last edited:

Reply to Identifying live, neutral and earth in outdoor festoon lighting in the UK Electrical Forum area at ElectriciansForums.net

News and Offers from Sponsors

  • Article
Join us at electronica 2024 in Munich! Since 1964, electronica has been the premier event for technology enthusiasts and industry professionals...
    • Like
Replies
0
Views
380
  • Sticky
  • Article
Good to know thanks, one can never have enough places to source parts from!
Replies
4
Views
956
  • Article
OFFICIAL SPONSORS These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then...
Replies
0
Views
1K

Similar threads

  • Question
Or just save all the agro and get a proper sparks round for 45 minutes to test the supply cable and re-fit the socket 'properly'
2
Replies
19
Views
2K
I opened up the CU again and the round junction box above and what I found was the blue and brown wires coming in from the wall just above the 15a...
2 3
Replies
33
Views
2K

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.
Back
Top