Your home has plugs that connect electrical appliances to the mains. Standard electrical plugs of this sort should never become hot. If one does, you should switch off the appliance, switch off the socket on the wall and remove the plug from the socket. Reasons for a plug to heat up include an incorrect fuse, the wrong cable, a loose or poor wiring connection, corrosion, a faulty appliance or a problem with the socket.
An incorrect fuse can lead to a plug becoming hot. A fuse is a safety feature of a plug that removes excess current when this is too high for an electrical circuit. However, fuses come in different amp ratings and you must ensure the rating matches the wattage of your appliance. For example, a lamp with a 60-watt bulb can manage with a 1-amp fuse. But a 2.5-kilowatt electric fire requires a 13-amp fuse. To calculate the correct fuse rating, divide the number of watts of an appliance by 230 volts. Use the first fuse that has an amp rating above the result of this calculation. Fuses are 1 amp, 3 amps, 5 amps and 13 amps.
The cable between an appliance and a plug may be too small. If so, the cable's wires might not be able to handle the electric current passing to the appliance. The plug may become hot as a result. To check if the cable is the wrong size and the cause of the problem, you might need to consult an electrician.
Loose or poor wiring connection
The wiring in a plug sometimes becomes loose or frayed. This may happen when someone trips on the wire and jerks it or accidentally pulls it. Power may still flow to the appliance, but loose or frayed wiring could create sparks and heat the plug.
Plugs and wires may corrode over time. When this happens, corrosion may cause a plug to become hot. Even if an old plug appears to be working well, check it regularly for signs of wear and damage, and replace it when necessary.
A plug, its fuse and wiring might be correct and secure. A plug might still become hot, though, if the appliance is faulty. A defective appliance can create problems with the electrical circuit, which might in turn cause the plug to heat up.
You may have a poorly-wired electrical socket. When you put a plug in the socket, the plug heats up. If you cannot find any other cause for a plug becoming hot, the socket may be to blame. Try putting the plug into another socket. If the plug does not become hot, the original socket could be faulty.