3x230

[Gardner]

You cannot fulfill the requirements of part P with an installation designed to any regs other than bs7671

Nowhere do the building regs say BS7671 must be used.

 

[Gardner]

Part p is an building reg, nothing to do with IET.

Exactly my point. I could wire a building with German regs, nothing holds me to BS7671.

 

[7029 dave]

Exactly my point. I could wire a building with German regs, nothing holds me to BS7671.

Not in the UK we adhere to BS7671

 

[davesparks]

Nowhere do the building regs say BS7671 must be used.

Approved document P, section 1, line 1:
"Electrical installations should be designed and installed in accordance with BS 7671:2008 incorporating Amendment No 1:2011"

 

[Gardner]

It is possible to design and construct an installation which uses such a supply in accordance with bs7671. However bs7671 is not law and so compliance with it cannot be described as legal. The law which governs electricity supplies in the uk is the electricity supply quality and continuity regulations (esqcr) which may prohibit such a supply from being provided to a customer.

Thanks

Under bs7671 you would need to break all conductors which are not referenced to earth at substantially the same time, so yes you would need to provide double pole switching for light fittings.

Got it. All MCBs are 2 and 3p. What part of the regs require 2p switching for light fittings? Not saying it does not exist but just want to have a reg reference.

Further to this you cannot use bs1363 plugs and sockets on such a supply as they are fused in one pole only, as a result the ring final circuit would not be useable. You would need to use a plug and socket system which is not fused or polarised, you may be able to use bs546 plugs and sockets for this.

Schuko plugs will be used with 16 amp MCBs. No rings either.

 

[Gardner]

Approved document P, section 1, line 1:
"Electrical installations should be designed and installed in accordance with BS 7671:2008 incorporating Amendment No 1:2011"

But its not mandated, is it? Should is not shall.

 

[davesparks]

Exactly my point. I could wire a building with German regs, nothing holds me to BS7671.

In Germany yes you can, however if you are in England then you abide by our rules.

As far as England goes:
The registration bodies would not accept it.
LABC would not accept it.
Insurance companies would not accept it.
The HSE would not accept it in an investigation if an incident occurred.
A Judge would not accept it if you were put on trial as a result of said incident.

 

[Gardner]

In Germany yes you can, however if you are in England then you abide by our rules.

As far as England goes:
The registration bodies would not accept it.
LABC would not accept it.
Insurance companies would not accept it.
The HSE would not accept it in an investigation if an incident occurred.
A Judge would not accept it if you were put on trial as a result of said incident.

Fair enough. But to be honest, I remember on another forum saying BS7671 should be publicly disclosed for free because its law with posters saying its not law since part P does not mandate it... A bit confused.

But anyways... if the sockets at Bayonet, do I still need DP switching?

 

[davesparks]

But its not mandated, is it? Should is not shall.

That is a technical point which would take some expensive legal professionals to argue over.

I think the general idea is that nobody would be so downright stupid as to work to non-uk regulations in general installations in the uk! It would make you uncompetitive in terms of price and get you a terrible reputation when all of your customers find out that you have not worked to uk regulations.

 

[Gardner]

That is a technical point which would take some expensive legal professionals to argue over.

I think the general idea is that nobody would be so downright stupid as to work to non-uk regulations in general installations in the uk! It would make you uncompetitive in terms of price and get you a terrible reputation when all of your customers find out that you have not worked to uk regulations.

Makes sense.

For those who dont believe 138/240Y is not a real DNO supply voltage here is the tag on a transformer which is used in a 3 phase bank to provide a 240 volt 3 phase L-L supply:

 

[davesparks]

Fair enough. But to be honest, I remember on another forum saying BS7671 should be publicly disclosed for free because its law with posters saying its not law since part P does not mandate it... A bit confused.

But anyways... if the sockets at Bayonet, do I still need DP switching?

BS7671 is not law but it is referenced in law. Part P is only concerned with domestic installations.

The type of lampholder is irrelevant to the switching requirement, the requirement is that all line conductors (ie. all conductors not connected to earth at source) be broken.

The question of lampholders is a seperate issue. The regulations require that the outer contact of ES lampholders be connected to neutral, therefore you cannot use a two phase supply with an ES lampholder. You can use pretty much every other type of lampholder including BC, GU10, GX, GY etc etc

 

[Gardner]

BS7671 is not law but it is referenced in law. Part P is only concerned with domestic installations.

So the option is indeed their to wire something to other regs?

The type of lampholder is irrelevant to the switching requirement, the requirement is that all line conductors (ie. all conductors not connected to earth at source) be broken.

Is this mandated by any particular reg? I just dont know how I would go about 2 way switches.

The question of lampholders is a seperate issue. The regulations require that the outer contact of ES lampholders be connected to neutral, therefore you cannot use a two phase supply with an ES lampholder. You can use pretty much every other type of lampholder including BC, GU10, GX, GY etc etc

Is BC bayonet? GU10 is easy to get with LED. Easy route to take with LED.

 

[davesparks]

So the option is indeed their to wire something to other regs?



Is this mandated by any particular reg? I just dont know how I would go about 2 way switches.




Is BC bayonet? GU10 is easy to get with LED. Easy route to take with LED.

Only as far as bs7671 being non-statutory is concerned. Your insurance would likely be void and you would open yourself up to a heck of a liability should anything go wrong!

I don't have a regs book to hand, but the section called isolation and switching would be a good place to start. I assume you own a current copy of bs7671 if you are designing to it?

BC is bayonet cap yes. LED gu10 is the cheap and easy option yes but are not great when compared to a fitting designed and built using an LED source from the outset.

 

[Gardner]

Only as far as bs7671 being non-statutory is concerned. Your insurance would likely be void and you would open yourself up to a heck of a liability should anything go wrong!

I don't have a regs book to hand, but the section called isolation and switching would be a good place to start. I assume you own a current copy of bs7671 if you are designing to it?

BC is bayonet cap yes. LED gu10 is the cheap and easy option yes but are not great when compared to a fitting designed and built using an LED source from the outset.

Sounds great, I will take a look at switching and isolation!

EFLI and disconnect times are still 0.4 seconds for TN?

 

[Lucien Nunes]

So as I understand it now, you are designing an installation outside the UK, where UK building regs do not apply, where the supply is not of the type provided by UK DNOs, but you wish to comply as far as possible with BS7671 or use the standard as the design framework. A lot of head scratching could have been avoided if this had been explained in the OP, as this is a forum primarily for UK electricians working to UK regs in the UK.

You substitute Schuko and radials for BS1363 and rings, to avoid the problems mentioned above, and provide DP OCP and isolation throughout. And then we get to 2-way light switching and I am going to hide behind a pile of DP relays!