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The 13 Amp PLUG. Fuse. Earth. Insulating Casing. Neutral. Live Wire. Cable grip. Flexible Copper conductors. FUSES IN ACTION. fault. Extra current melts the 5 Amp fuse wire cutting off the live supply. Fuses are the weakest link in a circuit, preventing fires.
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The 13 Amp PLUG Fuse Earth Insulating Casing Neutral Live Wire Cable grip Flexible Copper conductors
FUSES IN ACTION fault Extra current melts the 5 Amp fuse wire cutting off the live supply Fuses are the weakest link in a circuit, preventing fires. They consist of a short, thin piece of wire with a low melting point.
EARTH & FUSE
The earth wire and fuse - - - - - - - - - L Fault- Loose wire N
The earth wire and fuse - - - - - - - - - L Fault- Loose wire N
The earth wire and fuse L E N The earth pin is connected to the metal case via the yellow /green earth wire If a fault develops a larger current can flow down the earth wire and melt the fuse wire cutting off the supply on the LIVE wire
Errors in Wiring Plugs 1 2 3
Errors in Wiring Plugs 1 2 3
Errors in Wiring Plugs 1 2 3
Errors in Wiring Plugs 1 2 3 1. Bare wires showing 2. Proper fuse not installed 3. Earth wire not connected
Errors in Wiring Plugs 1 2 3 1. Bare wires showing 2. Proper fuse not installed 3. Earth wire not connected 5 4
Errors in Wiring Plugs 1 2 3 1. Bare wires showing 2. Proper fuse not installed 3. Earth wire not connected 4. Live and neutral swapped 5 4
Errors in Wiring Plugs 1 2 3 1. Bare wires showing 2. Proper fuse not installed 3. Earth wire not connected 4. Live and neutral swapped 5. Loose cable grip 5 4
A ring main circuit Why are sockets wired in parallel with each other ? The longest pin of a plug is designed to make contact with the earth wire
FUSES, EARTH WIRE AND PLUGS If your body has a resistance of 100 and you touch a live wire at 230V, what happens? Wet hands have a much lower resistance.
Safety with mains electricity * Replace broken plugs and frayed cables * Keep plugs & cables away from water or heat * Never overload a plug or socket * Don’t use wet hands when switching on or off Appliances with plastic cases do not need an earth wire Why not? The insulating plastic prevents users getting into contact with ‘Live’ components
CIRCUIT BREAKER Circuit breakers work quicker than fuses. ( saves lives)
CIRCUIT BREAKER They are easily reset by pressing a button
neutral melts live parallel earth series rubber – flexible, good insulator Brass – stiff, good conductor Copper – malleable, good conductor Stiff plastic – tough, rigid, good insulator
1a. A Fuse cuts off the supply if there is excessive current caused by a fault. 1a. A fuse is on the live side so that the appliance remains safe from the live voltage. 1a Circuit breakers work quicker than fuses.( saves lives) New switch location yes The off switch should prevent the live voltage reaching the element