ABSTRACT
Some typical loadings of domestic appliances are given in Table 6.1 .
Conductors and the current-carrying components of accessories (e.g. switches, fuses, circuit breakers, socket outlets and plugs) must be large enough to carry the maximum current which the connected apparatus can cause to flow, without overheating or being overstressed. Conductors and accessories are rated in terms of current in amperes. Therefore, before the required size or ‘rating’ of a
conductor or accessory can be determined, the consumption of the connected apparatus in amperes must be calculated. This is known as the design current ( I b) of the circuit and can be determined from
Ib Power (watts)
Volts
As an example, a 1 kW/230 V electric fire takes 4.35 A when connected to a 230 V supply.
