Power overload

cue

How can you work out how many items you can run off a 13a socket before it will blow? I know there is some sort of simple formula to work this out but I do not know what it is.

Michael Collins

Well the current in amps consumed will be the sum of the wattage of your devices divided by 230. (Because Current = Power / Voltage, and the supply in Ireland is nominaly 230 V, but it can be lower at any instant - so maybe divide by 220 V to be on the safe side.)

Also bear in mind that, in addition to the above warning, in practice you won't quite make it to 13 amps without blowing the fuse by this method, as there's a thing called reactive power which bounces back and forth between some devices and the supply (you arn't charged for this, since you don't actually use it!).

kevmy

Above seems true but remember that all the devices plugged in to a socket might not be drawing power at the same time eg. if you have 4 things plugged in and 2 are on standby then the fuse probably won't blow