Basic Electrical Maintenance
How to do Electrical Maintenance Safely
Connecting a Plug
Connecting a plug is simple but, for safety’s sake, it’s vital that you get it right.
- Remove the outer sheath of the cord to a length of about 30mm, exposing the three inner flexes. When doing this, ensure that you do not damage the insulation of the flexes. Strip the last 6-8mm of insulation off each inner flex. You’re now ready to make the connection.
- When connecting a three-core cable, the brown insulated wire goes to the live pin (marked with an L on the plastic of the plug) and the blue insulated wire (the neutral wire) goes to the small pin (marked with an N on the plastic of the plug) Alternatively, the plastic will be marked blue and brown.
- The wire with green and yellow striped insulation is your earth wire and this goes ONLY to the large pin at the top of the plug, furthest from the point at which the cord meets the plug. NEVER connect this wire to either of the small pins.
- Ensure that the two flaps of the plug grip the cord’s outer insulation or the saddle clamp that is used in some types.
Now here’s a staggering thought! When you’re connecting two or three core cords together, staggering the connections will ensure that your connection is safer. Just ensure that you connect earth to earth, live to live and neutral to neutral.
Replacing a Switch
Safety first – ensure that the mains power is turned off, that the family is aware of what you’re doing and that you have pasted a big notice next to the mains switch telling everyone to LEAVE IT ALONE! Turn off ALL the switches on the main circuit board. Switch the TV or stereo or a mains-powered radio on and crank up the volume so if anyone ignores the notice or forgets that you’re working and turns on the power, you’ll get adequate warning. Now you can start.
- Remove the cover plate and the two securing screws for the faulty switch. For extra safety, mark each wire’s position. Note that the fixed wiring in the suburban home has a different colour coding to that used on appliances: Red is live, black is neutral and green is earth.
- Connect each wire in turn, double checking at each stage.
- Once you are completely satisfied that your connections are sound and correct, replace the switch in the wall, using the securing screws to fix it into position.
- Now (first turning off the TV or whatever you have set up as your DIY alarm) go to the main distribution board, turn the mains switch back on and, one switch at a time, turn on the individual circuits. If the earth leakage trips at any stage, there’s a chance that you made a mistake when connecting up the new switch. If all is fine however, switch off everything again, replace the cover plate on your new switch and plug in a bedside light. Now switch everything back on again and switch the light back on.