It follows me wherever I go.

Goody · Jul 2, 2011

I went to a friend’s to install a socket for minor job for assessment and met with 16 mm tails again. I have attached the pictures here. If I call DNO they will take ages to come down but my assessment is at the end of this month, don’t know what to dooooo!

I have done a similar post here -> http://www.electriciansforums.net/electrical-wiring-theories-electrical-regulations/37217-question-about-16-mm-meter-tails.html

[ElectriciansForums.net] It follows me wherever I go.

MarkieSparkie · Jul 2, 2011

Hi Goody, There also appears to be another problem, the close proximity of that gas pipe to the cabling, meter and supply head. :32:
OSG 2.3 and 7.4.3 refer:
"BS 6891:2005 Installation of low pressure gas pipework in domestic premises, Clause 8.16.2; Gas installation pipes must be spaced:- a) at least 150mm away from electricity meters, controls, electrical switches and sockets, distribution boards or consumer units. b) at least 25mm away from electricity cables for pipework up to 35mm diameter, over 35mm diameter separation must be at least 50mm. The separation distances can be reduced in a) a partition of non-combustible material is interposed. b) if the gas pipe is PVC wrapped or a pane of insulating material is interposed."

Deleted member 26818 · Jul 2, 2011

You and your blooming 16mm² tails, I dunno.

ezzzekiel · Jul 2, 2011

cant see why youre struggling with concept bud, does the work you are carrying out require the upgrading of the tails? does the service fuse size demand larger tails or is the demand suitable for the tails in question and are they in sound condition?

as mentioned by soin proximity to gas is an issue , but you will always find this on most older installs that gas and electric tend to share the same location and little can be done about it now.

mogga · Jul 2, 2011

oops sorry

mogga · Jul 2, 2011

the tails from meter to henly block CANT BE replaced by you as you arent autherised to do this hence your work stops at henley block so long as you have informed DNO that the tails require upgrading then IMO you have done your bit <br>Meter n gas pipe proximity could be solved with a cupboard around meter/cu I think Altho as it seems to have been there since before the regs brought in seperation id note it and recomend gas pipe to be moved by customer

Deleted member 9648 · Jul 2, 2011

As long as there is no evidence of heat damage or overloading on the tails,and your socket is not going to add significant load,just note it under 'comments on the existing installation'......I've yet to see any problem with soundly connected 16mm tails on a standard domestic install,and I dont expect I ever will.

Octopus · Jul 2, 2011

Its bad enough explaining that you need RCD sockets on older installations, but telling everyone they need upgrades to their meter tails could do untold damage to our industry.

25mm tails are (IMHO compulsory) on new installations and rewires.

Goody · Jul 4, 2011

Guys, thanks for all the advices.

Although this house shows signs of recent re-wiring, the tails & gas pipes should have been there since 60’s or 70’ and I am only adding a humble single socket as part of my assessment and these things really make me panic.

This additional single socket on the “Downstairs Ring” would be used for a vacuum cleaner of 1000 watts (maximum) drawing 4.35 amps when used. Getting this much additional current through 16 mm tails shouldn’t melt the cable and I am hence going to do the following:

1. Inform DNO to upgrade the tails and note it down on the “comments on the existing installation”
2. To be on the safe side, I will note down the total current requirement for the existing installation.
3. Recommend gas pipe to be moved by customer.
4. There is also a connection to the external garage fed by a 2.5mm SWA that is not properly glanded at the CU and I will mention this on the “comments on the existing installation”

Or, instead of adding a 13 amps socket on the spur I can add a lighting circuit with a single light socket (100watts/230volts = 0.43 amps)

Is there anything else I should do to avoid sticky situation during assessment? Thanks

malcolmsanford · Jul 4, 2011

Or, instead of adding a 13 amps socket on the spur I can add a lighting circuit with a single light socket (100watts/230volts = 0.43 amps)

Sorry you are going to have to run that one by me again.

Goody · Jul 4, 2011

malcolmsanford said:
Or, instead of adding a 13 amps socket on the spur I can add a lighting circuit with a single light socket (100watts/230volts = 0.43 amps)Sorry you are going to have to run that one by me again.

Hi, malcolmsanford, this light socket circuit is via a 5 amps FCU spurring off the ring. Is it a bad practice or the reg says it's wrong? Thanks.

Deleted member 26818 · Jul 4, 2011

If the socket-outlet is intended for general use, then it could be expected to have a load connected that is greater than 1kW, perhaps a 3kW fire for instance.
It used to be under the 16th, that before any addition or alteration was conducted, that the existing equipment had to be assessed to determine whether it was adequate for the additional load caused by the addition or alteration.
Now under the 17th, it has to be determined that it is adequate for the safety measure applied to the addition or alteration.
As such as long as the Zs are low enough to allow ADS, I can't imagine that the size of the tails will be an issue. Especially if the main fuse is rated at 60A.

Deleted member 9648 · Jul 4, 2011

Goody said:
Hi, malcolmsanford, this light socket circuit is via a 5 amps FCU spurring off the ring. Is it a bad practice or the reg says it's wrong? Thanks.

I think the confusion has arisen as you were installing a socket for general use which has now morphed into an FCU for a light!
Nothing wrong with using an FCU off the ring to feed a light where appropriate,however if there is a dedicated lighting circuit available for the area it would always be better to use that, rather than have lights on the ring and a lighting circuit in the same area.