New build outside light

[clematis432]

Hi, is it a requirement to run an earth wire to outside light(although its double insulated) or is it probably just best practice ? I was replacing my son,s existing outside light on a new build house with a pir security light but found there was no earth to his existing light. Thanks

 

[Midwest]

Please. I don’t drive ‘a van’.

You must of had a Freudian slip then.

 

[Ray Pooley]

All electrical points require a cpc (earth wire) whether used or not

If you have an opportunity to provide an earth wire I would do so whether it's "written" or not.

 

[alasdairp]

I thought that "double insulated" allowed two-core flex and non-earthed chargers, etc, but the installation connection point (socket or ceiling rose, etc, including the switch) had to have the CPC present and terminated in some way (not just cut back). I did not this specifically mentioned. Any two-core installed cables I thought had to be SELV (i.e. no more than 50 volts rms - and floating w.r.t. earth).

 

[Jjc]

But where is it written? I'm not being pedantic, I can't find it in the book.

If nothing else its good practice. If the cpc is not terminated to the fitting then stick it on a terminal block . It's then available for future use. Why cut it off?

 

[sheppertonspark]

Since we are debating this here is my quandry. The regs say every item of equipment and accessory should have a c.p.c. available, common sense particularly for the situation originally posted, changing class 2 fitting for class 1. Problem is if you introduce an "earth" to a double insulated enclosure, by definition it is no longer double insulated. Can anyone answer this ??

 

[DPG]

Since we are debating this here is my quandry. The regs say every item of equipment and accessory should have a c.p.c. available, common sense particularly for the situation originally posted, changing class 2 fitting for class 1. Problem is if you introduce an "earth" to a double insulated enclosure, by definition it is no longer double insulated. Can anyone answer this ??

The earth is not connected to the fitting though. It is left unterminated and insulated.

 

[sheppertonspark]

Yes it's not connected, but by it being inside the fitting I believe it makes it no longer able to classed as "double insulated".

 

[sheppertonspark]

Catch 22

 

[DPG]

I see your point but I personally don't see it that way.

 

[Midwest]

Problem is if you introduce an "earth" to a double insulated enclosure, by definition it is no longer double insulated. Can anyone answer this ??

A lot of room stats etc are Class II, but an 'earth terminal is provided for external earth wiring continuity' (Honeywell).

 

[DPG]

Double insulated appliances 'do not require an earth'. Doesn't mean one cannot enter the appliance.

 

[Pete999]

Since we are debating this here is my quandry. The regs say every item of equipment and accessory should have a c.p.c. available, common sense particularly for the situation originally posted, changing class 2 fitting for class 1. Problem is if you introduce an "earth" to a double insulated enclosure, by definition it is no longer double insulated. Can anyone answer this ??

Your not introducing an Earth Mate, you are providing a cpc, incase the client. owner whoever decides to change the light fitting for a class 1 fitting, it's not connected to the fitting, it's parked in a connector, beit Wago or Chock block, It's not connected to the class 2 fitting, can't believe this has take 85 plus posts to get through to people.

 

[alasdairp]

Yes it's not connected, but by it being inside the fitting I believe it makes it no longer able to classed as "double insulated".

In a way the best way to do it would be cut the CPC off at the enclosure end of the cable and seal the end of the cable with tape so that just the phase and neutral emerge. For outside lights self-amalgamating tape would be best. That would provide one level of insulation and the plastic enclosure of the luminaire would provide the second level. It would be important to seal the CPC inside the end of the outer insulation of the cable in oreder to achieve the double insulation - especially with regard to water ingress. Simply cut off inside the end would not strictly provide the second level as I understand it. A separately plastic enclosed connector block would also be acceptable.
Can anyone cofirm or deny my point earlier about the difference in rules between installation wiring and external two-core flex leads to the double-insulated light/device/appliance?

 

[Midwest]

In the case

Your not introducing an Earth Mate, you are providing a cpc, incase the client. owner whoever decides to change the light fitting for a class 1 fitting, it's not connected to the fitting, it's parked in a connector, beit Wago or Chock block, It's not connected to the class 2 fitting, can't believe this has take 85 plus posts to get through to people.

Nope, in the case of the Honeywell stats, they provide a terminal, although as most of its plastic, its not an issue.

https://www.google.co.uk/imgres?img...frfAhVMSBUIHWshAfMQMwhKKAEwAQ&iact=mrc&uact=8

 

[Midwest]

In a way the best way to do it would be cut the CPC off at the enclosure end of the cable and seal the end of the cable with tape so that just the phase and neutral emerge. For outside lights self-amalgamating tape would be best. That would provide one level of insulation and the plastic enclosure of the luminaire would provide the second level. It would be important to seal the CPC inside the end of the outer insulation of the cable in oreder to achieve the double insulation - especially with regard to water ingress. Simply cut off inside the end would not strictly provide the second level as I understand it. A separately plastic enclosed connector block would also be acceptable.
Can anyone cofirm or deny my point earlier about the difference in rules between installation wiring and external two-core flex leads to the double-insulated light/device/appliance?

Have to say I've done both, e.g. for extra low voltage fans. But I'm more inclined now to terminate the unused cpc inside the fitting. If the outer casing of the device was metal, I might consider not doing this.

 

[Pete999]

In the case


Nope, in the case of the Honeywell stats, they provide a terminal, although as most of its plastic, its not an issue.

View attachment 47270

So you are parking the cpc in a terminal that's mostly plastic that is NOT introducing an Earth/

 

[westward10]

In the case


Nope, in the case of the Honeywell stats, they provide a terminal, although as most of its plastic, its not an issue.

View attachment 47270

Do they state that stat is double insulated.

 

[alasdairp]

In the case


Nope, in the case of the Honeywell stats, they provide a terminal, although as most of its plastic, its not an issue.

View attachment 47270

How is that Honeywell Stat "double-insulated"??? Isn't it a single insulated control, like a normal plastic wall switch?

 

[Midwest]

Do they state that stat is double insulated.

Yep.

 

[GMES]

7 pages.

 

[Midwest]

7 pages.

This could be the epic you guys dream of

 

[Wilko]

@Midwest and Honeywell are in line with IEC 62257-7-1 ... an earth terminal may be provided inside a Class 2 device, see note 3 . Just doing my bit to keep the dream alive. Well, consume red wine at least.

 

[Toneyz]

Yes it's not connected, but by it being inside the fitting I believe it makes it no longer able to classed as "double insulated".

So why do I fit light fittings that are double insulated and come with a terminal to park the cpc?

 

[Judd]

I've just skipped to the end here so apologies if this has been mentioned
412.2.3.1 &
412.2.3.2

 

[John-]

I've just skipped to the end here so apologies if this has been mentioned
412.2.3.1 &
412.2.3.2

Boom, in ya face .