No earth in lights

[KFORDHUNTER]

This might be the thickest question ever but if a lighting circuit in a house has no earth you have to add one in don't you, or is there some way around it now with say class 2 fittings and plastic switches.

 

[PAUL M]

If you go on the niceic website download section there is a download titled changing a consumer unit in a property with no earth on lights that deels with this in detail,hope this helps.

 

[Nick Ward]

I would have thought that installing an 30mA RCD or RCBO protection to the circuit would be a solution.

Nick Ward

 

[bigal]

You can add to the aforementioned circuit but you have to make sure your part of the installion complies, ie if there is no cpc existing you can pick one up from a local circuit (same board) but it has to be 4mm. If it needs an rcd then youi have to add one. Having complied to the above you don't need to use class 2 fittings etc. Think I'm right in all that? Syure someone will correct me if I'm not>
Big Al

 

[Johnocd]

Hi,

This is my first reply, so I hope I am right in what say!! If not then I will be learning yet again!

If there is no cpc in the lighting circuit then protect by an RCD/RCBO. Change fittings and switch plates out for plastic and issue a method statement on changing a failed lamp element, i.e. non conducting step ladders etc. This is off course if there isn't the facility to retrospectively add a cpc.

 

[just add water sparks]

I would have thought that installing an 30mA RCD or RCBO protection to the circuit would be a solution.

Nick Ward

MMMmmmmh!!!!!! Yes,it would be a solution!!But surely an RCD or RCBO will only work with a c.p.c anyway????? as it has to have a balanced load.I would be grateful if someone can confirm this!!!!! Thank you.

 

[wayne]

personally i was of the opinion that a rcd detects an imbalance between ph &n usually caused by an earth fault .the o in rcbo is for overload .
is this one of those threads that tries to trip people up?

 

[tony.towa]

Spot on Wayne.

A RCD detects an imbalance between phase and neutral and will "trip out" at an imbalance more than 50% of its rating (ie a 30 mA device will trip out between 16 and 30mA). This imbalance is generally as a result of an earth fault however it does not require a cpc to function (check out wiring in some parts of Europe where no cpcs are installed but RCD incomers are used).

A RCBO meets the characteristic requirements of an RCD however also incorporates the functions of a mcb having short circuit and overload protection capabilities.

 

[just add water sparks]

thanks guys

sorry not long joined this forum,i must be blind where the hell do i click on to post new topic???????????????? thanks

 

[wayne]

the head boy will be along to fill you in shortly
as tony says you need an earth path ,even if its through you! and not a cpc