Ready to hire?

Post your job in minutes, browse real reviews and choose who to speak to.Post a job

Need some tips or advice?

Electrical

Earth wire on Double inslulated lights

Anonymous user 23/02/2024 - 3.03 PM

We have had some double insulated LED down lights installed in our new extension, by our builder. The instructions for these state as below: “This unit is double insulated and must not be earthed. If there are any incoming earth cables they must be joined together The junction box with the lights only has a live and neutral connection, so the builder has joined the earth wires together in a separate terminal block. However the electrician who is signing off the new electrics in the build has said the earth must be in the same junction box as the other wires. It does not state this in the instructions and if this was the case why would the item only be supplied with a junction box for only live and neutral wires? We need all the new electrics signing off for building regs, but I don’t want to un necessarily spend money paying to the electrician to re-wire all the new recessed lights. Can anyone advise if there is an electrical regulation that does state that earth wires for double insulated items must be in the same junction box or can it be simply joined in a separate terminal block?

Are you a tradesperson and able to answer this question?

3 Answers

Anonymous user

The earths should be joined together in a double insulated connector block and sleeved and not to the double insulated item. This protecting the continuous earth path. They should perform an R1+R2 test and a Zs test to confirm the state of the lights. There is no reg stating they have to be in the same block.

Answered4 July 2016

Anonymous user

If you used an electrician to carry out your electrical work instead of a builder, you wouldn't have this issue. Firstly, your electrician is working to BS7671 (wiring regulations) and not manufacturer instructions. Secondly, by way of your description, it could be yielding other issues like basic insulation being visible outside of an enclosure. Due to using a builder and not an electrician to do your electrical work, you now need an electrician to 3rd party certify it to LABC. So you can either accept your current spark's opinion, or you'll have to find another. At the end of the day, it will be the spark signing the work over to LABC who then becomes liable for it so it's right that he is wanting things done properly.

Answered8 July 2016

kevin cassidy building contractors

Rating: 5 out of 5

Accrington

Although double insulated fittings are used regulations state earth facility must be present. Its not clear where the earth is terminated but all cables should be terminated inside a junction box.

Answered4 July 2016