Wiring replacement switched metal BC lamp holder - help please

[Mutley56]

dear all,

I need to wire in a replacement switched metal BC lamp holder for a table lamp. The lamp stand is metal and needs to be earthed. The lamp holder has a small hole inside with a screw and this is for the earth wire presumably. The other wires screw into terminals on the plastic part of the fitting, which also has a terminal for an earth wire. So the question is, does the earth wire screw into the metal part of the fitting only, the plastic terminal only or somehow screws into both the metal holder and the plastic part of the fitting. I attach pictures to help.

Thank you in advance for your help.

Mutley56

 

[winston1]

It goes to the metal part of the fitting. I can't see an earth terminal on the plastic part anyway.

 

[Iggifer]

How does the lamp holder attach to the base? Does it screw in? It looks like it might just sit in, but that can't be right.

As winston has said, take the earth to the metal part, although the brass middle terminal looks like an earth terminal to me,

 

[winston1]

, although the brass middle terminal looks like an earth terminal to me,

It is not a terminal and has no terminal fixing screw.

 

[333rocky333]

To me it looks like the earthwire goes in the plastic bit, then when the plastic bit is pushed in it will automatically earth the metal base by rubbing against it.

I would also say the screw in the metal base is to lock the thread and not an earth terminal, you loosen the screw, screw base onto thread, retighten screw, this stops lampholder twisting on the thread when removing bulb.

Looking inside the base thread you should see where the screw protrudes and wedges the thread

 

[Mutley56]

Thanks all, there is an earth terminal in the plastic part as shown is tjis extra picture, I had to bend the copper bit back a bit

 

[Mutley56]

The whole metal fitting does screw onto the lamp stand

 

[Mutley56]

So if I insert the earth wire into the hole under the screw shown in picture 3, then this will make contact with the earth terminal section shown in pictures 4 and 5 via the small screw head. Does that sound likely and is this the normal way that these fittings are wired up?

Thanks in advance for your advice.

Mutley56

 

[333rocky333]

The metal tag you have mangled up is what earths the base when pushed in, it only brushes the side, as said I dont think there is an earth connection in the base, just a locking screw which also when tightened helps continuity of earth from the base to the thread.
It seems odd you had to mangle the tag to access the screw though.

 

[Mutley56]

Thanks for the replies. I look at it again tomorrow. Cheers

 

[securespark]

I have seen brass lampholders with a earthing terminal inside the base.

What I have done in the past is run the earth to the casing and out again to the terminal on the gubbins.

 

[securespark]

It goes to the metal part of the fitting. I can't see an earth terminal on the plastic part anyway.

It is not a terminal and has no terminal fixing screw.

Just because you can't see it does not mean it does not exist!