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BS 1363 plugs (the common 13amp appliance plug used in the UK) are required to carry a cartridge fuse which must conform to BS 1362.
BS 1362 specifies sand-filled ceramic-bodied cylindrical fuses, 1″ (25.4 mm) in length, with two metallic end caps of 1/4″ (6.3 mm) diameter and roughly 1/5″ long.
For the convenience of users, appliance manufacturers have standardised on two plug fuse ratings so these days most modern appliances come fitted with either a 3 amp or 13 amp fuse:
- For appliances up to 700W a 3A fuse should be used.
- For appliances over 700W a 13A fuse should be used.
However 5 amp fuses are still commonly available and may have been specified for use with older appliances. The safety documentation that came with your appliance will specify which fuse to use but if you don’t have this use the guide below for older appliances:
- For appliances up to 700W a 3A should be used.
- For those between 700W and 1200W a 5A fuse should be used.
- For appliances over 1200W a 13A fuse should be used.
Modern electrical appliances will have a sticker or plate showing the maximum power consumption in WATTS (W).
Click here for How to wire a standard 13 amp appliance plug