Electrical Safety Flashcards
What colour is the neutral wire
Blue
What colour is the live wire
Brown
What colour is the earth wire
Green and yellow
Describe what earthing is
The case must be attached to an earth wire as it can never become live
What does it mean if an appliance is double insulated
The appliance has plastic casing and no metal parts are showing
The appliance does not need an earth wire
Explain how earthing and fuses prevent fires and shocks
If a fault develops in which the live wire touches the case, due to the case being earthed, a big current flows through the live wire, the case, and the earth wire
This surge in current melts the fuse which cuts off the live supply
This isolates the entire appliance making it impossible to get an electric shock, it also prevents the risk of fire caused by a large current causing a heating effect
Explain the advantages of circuit breakers
They are faster than fuses as they can detect far smaller current changes
They are operated via a switch so can be reset so do not have to be replaced like safety methods such as fuses do
