I was under the impression for BS7671 you have to have fault protection for all cables, and overcurrent where necessary.
Overcurrent has been dealt with through assessement of max demand for the installation.
The fault protection for the tails is only by permission with UKPN, so if UKPN has no bearing, surely that means it would be unsatisfactory by default due to no valid fault protection? If they only allow 3m if they are happy for their fault protection to be used, then that's that?
I thought the same until I read through a load of posts.
IET Forums - EICR - https://www.------.org/forums/forum/messageview.cfm?catid=205&threadid=70233
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Not BS7671 as such, but in the paperwork from a well know DNO..
If you want connection, you need ot do what they ask for.
4.6 Meter Tails
Standard 25mm2 copper double-insulated conductors (meter tails) from the meter to the cut-out shall be provided and installed by the appointed meter operator.
Standard 25mm2 copper double-insulated conductors shall be provided and installed by the customer from the consumer unit for connection by the meter operator into the outgoing (load side) of the meter.
BS 7671 Regulation 433.2.2 requires a maximum three metres distance between overload protection devices and their source,
therefore the customer shall provide and install an intermediate switch fuse or isolating switch if the distance between the meter and consumer unit is greater than three metres.
The customer should seek professional electrical advice to determine the protection equipment that is appropriate for the customer given the impedance at the cut-out and the design of their installation as UK Power Networks is unable to advise on these aspects.
Meter tails shall not be installed or run inside the cavity wall of a building other than passing directly through the wall.
Tri-rated cables shall not be terminated onto UK Power Networks equipment.
quoted from
page 6 of the
ENGINEERING DESIGN STANDARD EDS 08-0129
LV CUSTOMER SUPPLIES UP TO 100A SINGLE PHASE
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