2 Amp appliances

[barliow]

Hi everyone,

I'm not an electrical expert so I have very little clue about amps, watts and their relationship. So, if you would be so kind as to help, please imagine you're talking to a small child in any explanation you might provide

I have just moved into a new-build house which includes rounded three-pin sockets controlled by a wall switch. I've managed to work out that a 2 amp plug fits these sockets, but for the life of me I can't find any websites that list appliances with a 2 amp plug attached to them. Everything seems to use standard plugs. So my questions are:

1. Does anyone know where such appliances can be bought?
2. Can these sort of sockets be used for both floor lamps and table lamps? I'm most interested in floor lamps.
3. Can I just buy some 2 amp plugs and attach them to the lamps I have already bought?
4. If the answer to 3 is yes, then presumably there is a limit to how much power the lamp is allowed to draw from the socket. This is where I get really fuzzy. One of the lamps has a maximum 250 watt father light and a max 50 watt child light. Can this be plugged into the 2amp socket?
5. If the answer to 4 is no, then what if, despite the fact that maximum bulbs the lamp can are 250w and 50w, I just used a 100w and 50w bulb, or a 50w and a 50w bulb. Would that make a difference?

Any explanation would be greatly appreciated.

Thanks.

 

[TicklyT]

I believe it is now a legal requirement that appliances are supplied with 'an appropriate plug already fitted'. As most are plugged into 13 Amp sockets, they are all usually supplied with 13 Amp plugs.

The sockets can be used for table lamps or standard lamps.

You can change the plug on a table lamp or standard lamp for a 2 Amp plug, but bear in mind there is no fuse in a 2 Amp plug. The wiring is only protected by the MCB in the consumer unit. Some would argue lighting sockets should have their own appropriately rated fuse associated with them, and some would prefer to use 5 Amp plugs and sockets, as their rating is nearer the rating of the MCBs normally used to protect lighting circuits.
Often an MCB is more sensitive to faults than a plug top fuse, so a 6 Amp MCB can trip before a 3 or 5 Amp fuse would blow anyway.

The maximum current from a 2 Amp outlet is.. er... 2 Amps. The relationship between Watts and Amps is governed by the supply voltge. In the UK it is normally considered to be 230 Volts.
If you know the rating of all the lamps in Watts, add them together and divide the total wattage by the supply voltage, the result is the current in Amps.

So a 40 Watt lamp will draw 40/230 = 0.174 Amps.
Or a 100 Watt lamp will draw 100/230 = 0.435 Amps.

Or 250 Watts + 50 Watts = 300 Watts. 300 Watts / 230 Volts = 1.3 Amps.

Or a 500 Watt lamp will draw 500/230 = 2.174 Amps. That's a bit too much for a 2 Amp socket (Not to worry, it would be a bit too bright for a domestic table lamp anyway )

You can use whatever lamps you like in a fitting, providing the rating of the lamp does not exceed the rating of the fitting.

Incandescent lamps are going the way of the gas mantle and being replaced by low energy lamps, so you may find you only need, say, 8 or 11 Watt low energy lamps to provide the same amount of light as 60 watt incandescent lamps.

 

[barliow]

Great explanation - many thanks.

Just two more stupid questions:

1. If the max rating of the lamp is 250w, but I actually use a bulb rated at 100w.. am I correct in thinking that I calculate the current based on the 100w figure?
2. Is the 2-amp limit literally 2-amps per socket or is it potentially 2 amps for several sockets? I only ask because one wall switch controls the power to multiple sockets, so I don't know if the surrent is shared in some way...

Thanks again.