Overview of cable rating.
The table gives you an idea of current carrying capacity of your Anglepoise Lamp flex.
Remember the figures are a starting point if you squeeze cables into access holes bunched with other monitor or computer power cable heat generation may affect flex current rating.
More heat from cable running behind radiators or trapped/squeezed/sharp bends etc can lower cable capacity.
As most lamps will not have more than a 100watt bulb in them a 0.5mm flex should be fine. Remember to fit a MAXIMUN of 3 amp fuse a 1 or 2 amp is better (1 amp fuse is good for up too 240 watt bulb).
Be safe and remember if you fail to put a correct size fuse into the lamp plug, for example leaving in a 13amp fuse, then the cable will melt and burn before the fuse pops, so be warned.
It is important to choose the correct size flex when connecting to the mains. The wire has to be the correct size so that it can cope with the power demands of the device. The size stated for flex is given in mm2 and this measurement is actually the cross sectional area of the wire inside. The larger that area the higher the current it can carry.
If a flex is used which is too small for the amount of current passing through, it becomes dangerous. This results in the wire overheating and causing a serious safety risk. The table below gives typical values of flex size available plus corresponding current rating and maximum power ratings.