Earthing lamps

[Rich#1984]

I'm thinking of making a steel floor lamp with a earthed bacolite bulb fitting my question is does the steel it's self need earthing ??

 

[Edward Teach]

Yes

 

[rikrobson]

what he said

 

[Alan Reynolds]

All metal electrical fittings should be earthed. I’ve not seen a Bakelite light fitting that could be earthed as it’s an insulator.

 

[8ob]

Will this need cross bonding to the nearest rad tail to comply let the regs rain down on us

Bob

 

[dobbslc]

All that nonsence stopped a good few years ago!

 

[dan.taylor.1]

As above, yes, but you'd struggle to get a lamp holder in bakelite with an earth so earth it at the base and run the other 2 conductors up to the lamp holder

 

[mtt.tr]

Depends on how you run the cable.


If for instance you ran flex to a double insulated lamp holder then no.

 

[skotl]

Depends on how you run the cable.


If for instance you ran flex to a double insulated lamp holder then no.

Is that still the case if the flex runs through a metal base or tube, though? I'd have thought you'd still need to earth that in case the flex chafed on the casing

(that said, wife just bought a copper lamp that came with an [illegal] European two pin plug...)

 

[jimbo84]

Is that still the case if the flex runs through a metal base or tube, though? I'd have thought you'd still need to earth that in case the flex chafed on the casing

(that said, wife just bought a copper lamp that came with an [illegal] European two pin plug...)

You'd have to meet specific criteria like insulating glands at every point that the cable enters or exits a tube, any pinch points etc. It's far easier just to earth the metal components of the lamp.

Very few metallic light fittings that you buy that are class II are actually class II or will fail to maintain the class II for any length of time, even more so with the garbage ceiling lights sold by the sheds, that you're expected to fit in place of a loop in loop out ceiling rose by the time it's been installed it is nowhere even close to being classed as double insulated.

 

[mtt.tr]

Look at it like this, my DeWalt chopsaw is all metal minus the motor, the flex runs through the metal but it's deemed class II and needs no earth as it's double insulated


Though if I'm makeing a metal lamp I would use a brass lamp holder as they look nicer so in that instance I would earth the lot and probably run single core wire through it.

I would typically earth top and bottom using the earth core but keep it one continuous conductor

 

[brightspark]

Depends on how you run the cable.


If for instance you ran flex to a double insulated lamp holder then no.

correct the flex is double insulated through the metal in to the lampholder so thats not a problem . a lot of bought lamps are the same where the cable enters the fitting it should have a cable clamp fitted so that it cant be pulled out . put a brass lampholder on and only THEN it needs a 3 core flex and be earthed

 

[Barking Mat]

Just earth it, and eliminate the risk.

 

[brightspark]

Just earth it, and eliminate the risk.

there isnt any risk. class 2 is safer than earthed. if the earth wire gets damaged broken or pulled out from the plug the metalwork can become live

 

[Barking Mat]

there isnt any risk. class 2 is safer than earthed. if the earth wire gets damaged broken or pulled out from the plug the metalwork can become live

Got to live a little, gods sake, man !

 

[jimbo84]

Usually the first thing that happens on class 2 stuff is those crappy plastic glands they use come adrift and then the flex is free to rub against metal edges. Not uncommon for the outer sheath of the flex to stop where it enters and you're left with a thin layer of clear insulation over the standard flex insulation to maintain it's "double insulated" status, it isn't going to take long to rub through and then you have some live metalwork.

I'm convinced they only do it on the chinese stuff to save a bit of copper, putting a bit extra plastic rubbish in them is far cheaper.