Mains Electricty Flashcards
What are the 5 key parts of the plug?
Live wire Neutral wire Earth wire Cable grip Fuse
What does the live wire do?
Connected to the power station
Sends current to the device
Shock - if touched
What does the neutral wire do?
Completes the circuit back to the power station
What does the earth wire?
Acts as a safety feature
Used in devices with metal cases to reduce risk of electrocution
Not present in plastic cases devices
What does the cable grip do?
Holds out cable in place, so if someone pulls on the connections it could possibly pull the individual cables out
What can incorrect cables cause?
Fire, damage to device, not working
What do bare wires cause?
Could touch other parts and cause a fire
What happens if the cable grip is only gripping the inner cables?
Inner cable would become loose
Wrong valve fuse?
Lead to fire or electrocution
What could a cracked case cause?
Could expose wires leading to electrocution
Describe a fuse and uses:
- designed to stop too much current flowing
- made of thin piece of metal wire in ceramic case, melts if too much current
- Common fuses = 3A, 5A, 13A
What does insulation do?
Reduces the risk of electrocution
Some metal cases devices have all live parts insulated inside
What does a fuse do for safety?
If there is too high of current, the fuse will melt which breaks the circuit and turns the appliance off
Placed in connection with live wire
What do circuit breakers do for safety?
Works using electromagnets which opens a switch if the current gets too high
Connected through a circuit a board
Modern adaption of fuse
What are some advantages of circuit breakers?
Many different current eating available
Operate almost instantly
More reliable
Can be reset
