Code of Practice for the Electricity (Wiring) Regulations - 2009 Edition

(vi) be suitably insulated for the voltage of the circuits in which they are
situated.
(b) No strand of a stranded conductor in a cable core should be cut away in
making a cable joint or termination.
(c) Joints in non-flexible cables should be made by soldering, brazing,
welding, or mechanical clamps, or be of the compression type. All
mechanical clamps and compression type sockets should securely retain
all the wires of the conductor.
(d ) Joints in flexible cable or flexible cord should be made by using
appropriate cable couplers.
(e) Terminations of mineral insulated cables should be made with proper
accessories and tools as recommended by the manufacturers.
(f ) Cable glands should securely retain without damaging the outer sheath
or the armour of the cables.
(g) Other details relating to the workmanship of cable joint and termination
are described in Code 25D.
(h) Except for the following, every connection and joint should be accessible
for inspection, testing and maintenance:
(i) a compound filled or encapsulated joint;
(ii) a connection between a cold tail and a heating element (e.g. a
ceiling and floor heating system, a pipe trace-heating system); and
(iii) a joint made by welding, soldering, brazing or compression tool.
13D Other Requirements of Cables
(1) Voltage grading of cables for low voltage application
(a) PVC insulated non-sheathed cables to BS6004 and BS6007 should
be 450/750V grade.
(b) PVC insulated, PVC sheathed cables up to 35 mm2 to BS6004 should
be 300/500V grade. For cables greater than 50 mm2 to BS6346,
voltage grade should be 600/1000V.
(c) PVC insulated, PVC sheathed armoured cables of any size to BS6346
should be 600/1000V grade.
(d ) XLPE insulated, non-sheathed or PVC sheathed cables to BS7211
should be 450/750V grade and to BS 5467 should be 600/1000V
grade.
(e) XLPE insulated, PVC sheathed armoured cables to BS5467 and
BS 6724 should be 600/1000V grade.
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