Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 1 of 13 PowerPoint presentation Stripping and terminating flex Unit 105: Electrical installation wiring and terminations

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 2 of 13 Stripping and terminating flex Tools Electrician’s knife Wire strippers Terminal screwdriver Side cutters

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 3 of 13 Stripping and terminating flex There are several ways of removing the outer sheath, which is normally round in cross section: Measure the required length and carefully score (cut) around the sheath. Do not cut all the way through. Bend the flex back so that the sheath breaks through to the cores. When split all the way round remove the sheath with a slight twisting movement. Use wire strippers to remove the required insulation. Use the fingers to twist the strands in the natural twist direction. Double over if needed to fill terminal.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 4 of 13 Stripping and terminating flex Some wire strippers will also trim the outer sheath off. Side cutters can be used to trim the sheath back, either by scoring the outer sheath or by cutting down the outer sheath from the end of the cable. This method needs extra care and would not be suggested by many. It should be emphasized that any method done poorly is bad workmanship and any done well is acceptable. Do not stick to one method. Different situations will demand different techniques.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 5 of 13 Stripping and terminating flex Terminating lamp holders Bayonet cap Remove cover. Strip sheath to required length. Double over conductor if required. Place conductors in terminals and tighten. Place conductors (cores) under strain posts and replace lampholder cover. The sheath should be inside the cover with no cores showing.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 6 of 13 Stripping and terminating flex Terminating lamp holders Edison screw Modern E14 and E27 lamp holders are designed so that the outer contact cannot be touched when inserting the lamp. Polarity is not an issue. Older types require that the line is connected to the centre pin. Remove cover. Strip sheath to required length. Double over conductor if required. Place conductors in terminals and tighten. Place conductors (cores) under strain posts and replace lampholder cover. The sheath should be inside the cover with no cores showing

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 7 of 13 Stripping and terminating flex Terminating lamp holders Ceiling rose The ceiling rose normally has the flex terminals as the two outer terminals. These may be tunnel terminals where the conductor is held in place by a small machine screw. Alternatively, a flat-head screw may be used with or without a flat square washer. Make sure the conductor is laid in the direction of tightening the screw otherwise there is a tendency for the conductor to be forced out. After termination the cores should run round the strain terminals. No cores should be visible when the cover is in place.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 8 of 13 Stripping and terminating flex 13A Plug Most modern equipment is supplied with a manufacturer’s moulded plug, which cannot be re-used. The only replaceable part is the fuse, which is normally accessible on the underside after removal of the plug. Always find out why the fuse has blown before replacing it.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 9 of 13 Stripping and terminating flex When the cover has been removed the pins are (from the left, in a clockwise direction): Neutral Earth Line (which often has the fuse holder attached) The colours are: Neutral (blue) Earth (green and yellow) Line (brown)

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 10 of 13 Stripping and terminating flex 13A plug connection The terminals will most likely be a drilled pillar or a knurled nut on a stud: Remove the outer sheath Measure the length of core required. There is little spare room inside the plug Remove the insulation and tighten the core strands in the direction of lay (twist) If the conductor is of small diameter, double over and place in terminal but do not leave any strands outside the terminal. Tighten with a terminal screwdriver. If the stud type is used, lay the conductor around the stud in the direction it is to be tightened and tighten. Ensure fuse is right rating

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 11 of 13 Stripping and terminating flex Restraining clamp Plugs have a restraining clamp to hold the flex in place and hopefully prevent strain being placed on the plug terminations. This clamp may be in the form of a fibre or plastic clamp over the cable sheath of a plastic grip, which automatically pinches on the sheath and holds the cable in place. Make sure the clamp is in place and tightened (but not over- tightened). Replace plug cover.

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 12 of 13 Stripping and terminating flex Other terminations Learners who complete the above may perhaps attempt the following: Flex connection from 13A flexible outlet spur unit. Free end to appliance or connector block Cable connector such as 10A duraplug or similar 16A BS EN Plug with free end

Level 1 Diploma in Electrical Installation © 2014 City and Guilds of London Institute. All rights reserved. 13 of 13 Any questions?