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Steve e ashton  
#1 Posted : 10 January 2016 01:17:41(UTC)
Rank: Super forum user
Steve e ashton

I may be chasing a armour here.... Anyone heard of a change in standards (or IEEE regs) that may require all sockets to be individually locally RCD protected? I don't see any benefit if the circuit is protected, but a client insists he has been told by a trusted electrician... Is there a change on the horizon or is this a trade oversell ( as I suspect)?
jay  
#2 Posted : 10 January 2016 13:17:07(UTC)
Rank: Super forum user
jay

paul.skyrme  
#3 Posted : 10 January 2016 14:59:58(UTC)
Rank: Super forum user
paul.skyrme

Hello Steve,

There have been no specific changes, oh, it’s BS7671 of the IET wiring regs these days, or the IEE, as was, the IEEE is the American Institute. ;)

Ok, as far as sockets go.
I am guessing that this query has come up within the last few weeks.
BS7671 is NOT retrospective.
Any installations must be designed, constructed, inspected & tested to the version in force at the time of initial design.
Remember also that BS7671 is NOT LAW, one can chose to ignore it if you wish, however, HSE suggest that you would need to be able to prove that you met an equivalent level of safety.
They also suggest that if you comply fully with BS7671 then you will probably comply with EAWR.
BS7671:2008+Amd3:2011 came into force on 01/07/15, with one slight change for domestic premises being delayed until 01/01/16.
The requirements are that virtually all socket outlets rated @ <20A (thus including 13 A BS1363 & 16A EN 60309) are protected by a 30mA RCD there is a specification for this, however if it’s legitimate & 30mA then it probably complies.
The changes do not require a single 30mA trip per socket.
The RCD can be on a per circuit basis.
If you place 30mA RCD’s in series then there is no selectivity (discrimination), thus there is no specification to determine which will trip first.
This is normally only done by design for redundant protection in the event of the failure of a single RCD, it does get complicated as you then need to look at common mode failures etc.
That is not for this discussion.

Now, the electrician could be recommending RCD socket outlets for several reasons.
There may be no requirement to protect the cable by RCD, thus an RCD is not required within the distribution board.
The electrical readings may be such that an RCD is not required.
However, the sockets require RCD protection as they are <20A.
The loads connected to the circuit are critical to business, thus, in the event of a failure of a single device operating the RCD, it would operate in the socket outlet, not disconnect the whole circuit, thus ensuring business continuity.

The loads connected to the circuit could be very “leaky” by design.
Thus as long as there is no requirement to have an RCD at the distribution board, then RCD socket outlets would limit the potential nuisance tripping experienced by legitimately “leaky” equipment interrupting the business.

More information required to define what is and what is not acceptable.

It may well be that the electrician is not trying to upsell at all.
He may well be advising the best option for the business to ensure safety, compliance and reliability of the installation.

Noting that reg 314.1 (i) requires that the installation is divided such that inconvenience is minimised in the event of a fault.
Thus the electrician could have looked at the installation and the requirements and taken it upon himself as the designer to put the proposal forward that RCD socket outlets are utilised rather than a single circuit RCD.
Steve e ashton  
#4 Posted : 10 January 2016 15:15:44(UTC)
Rank: Super forum user
Steve e ashton

Brilliant response. Thanks Paul.
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