domestic energy and electricity Flashcards
what is D.C current?
direct current
what does D.C current do?
travels in the same direction around a circuit
what provides D.C current?
a battery
what is A.C current?
alternating current
what does A.C do?
current flow is constantly changing direction
what does A.C change between?
positive and negative
what does the live wire of a plug do?
carry the current/ voltage to appliance at a high voltage
what colour is the live wire?
brown
what does the neutral wire do?
carries current away at low voltage
what colour is the neutral wire?
blue
what does the earth wire do?
if live wire breaks, earth wire takes the current safely to ground
what colour is the earth wire?
green/ yellow
what is a fuse?
thin piece of wire which overheats and melts when a current of more than a certain value flows
how do you choose which fuse to put in the plug?
use c = p over v to find the rating and choose the fuse rating which is above that
what is an MCB?
miniature circuit breaker
what does an MCB do?
breaks the circuit if current goes above certain amount
what are the advantages of an MCB?
faster and resettable
what is an RCCB?
residual current circuit breaker
what does the RCCB do?
breaks the circuit
what are the advantages of an RCCB?
protects the user
what is the ring main circuit?
the wiring that connects appliances together in parallel
what are the advantages of using a ring circuit?
cables made thinner because there are two paths for the current
each part of the cable carries less current because it flows two ways
more convenient since sockets can be placed anywhere on the ring
individual operation of sockets
