Electrical Safety 2: Checking Answers

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Electrical Safety 2 Checking Answers

• Fuse

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Electrical Safety 2 Checking Answers
Melts if too much current flows Protects against
overloads and fires. Does NOT protect people
against shocks

• Fuse

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Electrical Safety 2 Checking Answers

• Thermal circuit breaker

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Electrical Safety 2 Checking Answers
Switches off if too much current flows. Works
using a little heater inside

• Thermal circuit breaker

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Electrical Safety 2 Checking Answers

• Magnetic circuit breaker

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Electrical Safety 2 Checking Answers
Switches off if too much current flows. Works by
a little electromagnet inside pulling a switch

• Magnetic circuit breaker

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Electrical Safety 2 Checking Answers

• RCDalso called RCCBs or ELCBs
• One brand is Power Breaker

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Electrical Safety 2 Checking Answers
Use these with lawn mowers and anything else
outdoors Switches off if the Live current and
Neutral current are not equal Protects people
from shocks switches off before a lethal
current flows through you.

• RCDalso called RCCBs or ELCBs
• One brand is Power Breaker

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Electrical Safety 2 Checking Answers

• Earthing

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Electrical Safety 2 Checking Answers
Normally this wire does nothing, but if theres a
fault the current goes this way instead of
through me! If a machine has a metal case, this
wire connects the case to the ground

• Earthing

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Electrical Safety 2 Checking Answers

• Double insulation

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Electrical Safety 2 Checking Answers
Plastic case, the machine has no exposed metal
anywhere Does not need an earth wire

• Double insulation

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Electrical Safety 2 Checking Answers
1. When a fuse blows, I should fix the fault
that caused it before I put in a new fuse
because...
(a) the new fuse will also blow(b) to remove any
danger
2. Circuit breakers are more convenient
than fuses because...
they are easier to reset
3. Three appliances that need earthing
e.g. fridge, freezer, computer, washing machine...
Two appliances that do not need earthing
e.g. hairdryer, TV...
End