Installing a 1960's Pull down light with no earth help!

[bernardgreen]

If the light is double insulated it should not be earthed.

I never cease to wonder why the wording is "should not be earthed" instead of "need not be earthed".

The only apparent logical reason is that not earthing the item prevents it being the return path for an electric shock from some other source.

In this lamp perhaps the case is not earthed to prevent shock to a person who, while changing a lamp, touches a live part and the frame at the same time.

If it is so old that it is not marked with a DI symbol AND it does not have an earth terminal then it should not be used.

Agree with that for items as found.

But where items can be modified to provide reliable and assured earth continuity to all exposed conductive parts then they could be safe to use.

 

[Fearofelectrics]

it is VERY important that the live (red) wire is connected to the cable in the light that goes to the center pins.

Assuming all three centre pins are connected together.

It looks like the screw cap holders are inside metal tubes without any insulating sleeve between them and the tube so this item is almost certainly not double insulated. Therefor the metal work does need to be earthed if it is to be safe in use.

Carbonised spider remains between holder and metal work could make a connection between lamp holder and the metal work.

Many thanks it means i will not risk it simple as that.
It amazing how much i have learnt just from this one issue! Many thanks.

I think I will be getting Someone in to finish up ![/quote]

 

[Fearofelectrics]

If the light is double insulated it should not be earthed.

I never cease to wonder why the wording is "should not be earthed" instead of "need not be earthed".

The only apparent logical reason is that not earthing the item prevents it being the return path for an electric shock from some other source.

In this lamp perhaps the case is not earthed to prevent shock to a person who, while changing a lamp, touches a live part and the frame at the same time.

If it is so old that it is not marked with a DI symbol AND it does not have an earth terminal then it should not be used.

Agree with that for items as found.

But where items can be modified to provide reliable and assured earth continuity to all exposed conductive parts then they could be safe to use.

Ok Fantastic I think I need to get in a pro to sort this out. or not use this particular light.

I'm am very grateful to all the participants, in this forum for there advice and knowledge.