Household electricity Flashcards
What does AC stand for
Alternating current
What does DC stand for
Direct current
Things running off batteries run off
DC
What is the frequency in the UK
50Hz
What is the PD in the UK
230Volts
What can measure voltage
Oscilloscope (and voltmeters)
Where do you measure the voltage on an AC reading on a oscilloscope
the peak
What wires are found in a 3 core cable
Live, neutral and earth wires
Why is copper wire used
Very good conductor
What wires do 2 core cables have
Live and neutral
How are plugs kept safe ( 5 )
1/ Tough plastic case (plastic doesn't conduct electricity) 2/ Flexible, plastic cable 3/ Cable grip, or cord grip 4/ Fuse 5/ Insulated wires
What does the fuse do
Melts if the current gets too high
What is the brown wire and where is it located
The live wire, the right
What is the blue wire and where is it located
The neutral wire, the left
What is the yellow/green wire and where is it located
The earth wire, the middle
What are the wires plugged into
Earth, live and neutral pins
What wire is not found in 2 core plugs
Earth wire
What appliances have 2 core cables
Double insulated appliances
What appliances have 3 core cables
Metal cases appliances
Why is the earth wire required for metal cases appliances
In case the live wire came into contact with the metal case.
Why does the fuse burn if anything goes in the earth wire
The wire has low resistance so current goes up and fuse detects this
What does RCCB stand for
Residual current circuit breaker
What does an RCCB do
adds a layer of protection
How does RCCBs detect problems
Detects difference in current between live and neutral wire
What are the advantages of RCCBs ( 2 )
1/ Quicker
2/ Can be reset
