Headings Mains Electricity Search Questions 
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Mains Electricity - Fuse.
A fuse is a safety
device which switches off an
appliance
if too large a current flows through
the Live
wire.
The fuse is connected between the
Live pin and the Live wire of a plug.
The fuse has a rating
printed on the outside in amps.
If the current going through the
fuse rises
above its rated value,
then the fuse "blows" (it melts) which turns off the appliance.
For example, if the fuse says
5 amps,
then a current greater than
5 amps will blow the fuse.
Fuses
are given different colours for different
ratings.
This is called colour
coding.
A 2 amp fuse is blue,
3 amp is red,
5 amp is black (or very dark
blue),
13 amp is brown.
A fuse has its own circuit symbol.
To understand how a fuse works in more detail,
we must look at the Heating Effect of
Current.
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