Electrical appliances sold in the United Kingdom must be fitted with a prewired plug in accordance with the U.K. Plugs and Sockets Etc (Safety) Regulations 1994 and as updated by European Union law.
Plugs in the UK are supplied with 3-, 5- or 13-amp fuses. The 13-amp fuses should be used in a plug for appliances that consume a large amount of electricity, such as fan heaters or kettles. While the task of rewiring or replacing a 13-amp plug is straightforward, it’s imperative you connect the correct colored wires to each of the three plug terminals.
Strip one and a half inches of plastic from the outside of the wire using a knife or wire strippers. The color of the three wires inside must conform to U.K. regulations: brown (live), blue (negative) and green or yellow (ground).
Strip a quarter inch of protective plastic from each of the three colored internal wires using a knife or wire strippers. U.K. color coding is brown, blue and green (or yellow).Twist the end of each exposed wire to stop the strands from separating.
Position the plug on a suitable table with the three prongs are showing. All U.K. plugs with 13-amp fuses have one prong at the top of the plug and two near the neck. Unscrew the central large screw from the base of the plug. Unscrew the two smaller screws at the neck of the plug enough to allow the wire to go under the band that will hold the wire in place. Some plugs have a plastic grip instead of a band. Remove the plug cover.
Turn the plug over to see the internal parts of the plug. There are three terminals on U.K. 13-amp plugs. The top terminal is the ground. The terminal on the right near the neck is the live terminal, which has the 13-amp fuse fitted in line with it. The one on the left is negative.
Feed the wire through the neck band with the outer plastic under the band. Loosen the screw, if necessary.
Unscrew each of the terminal screws a few turns. Don't unscrew too much, otherwise the screw will fall out.
Attach the green or yellow wire to the top (ground) terminal and tighten the screw.
Attach the brown wire to the right (live) terminal (it has the 13-amp fuse attached). Attach the blue wire to the left (negative) terminal. Ensure the screws are tight and the wires safely fastened. Push any protruding wire into the spaces between the terminals. Ensure the hole where the main screw goes is clear.
Tighten the screws at the neck of the plug to fasten the complete wire. Turn the plug over and screw the cover on the plug. Insert the plug in a socket to test whether the appliance operates.