why would they sell a 2A lamp switch?

Hi all,

I recently refurbished an anglepoise lamp for a friend of mine - it needed a new push switch at the back of its head along with a new bayonet lamp-holder - what was in there was a bit of a horror story:

Attachment 21731 Attachment 21732

The replacement switch I bought was one of these: http://www.diy.com/departments/bq-bl.../178021_BQ.prd

...and on the packaging it stated that the switch was rated for 2 amps. Currently I have a 3A fuse fitted in the plug - but I'm going to order a 2A, possibly even a 1A. My question is this, though: why would they sell a 2A lamp switch when it's all but impossible to buy 1A* and 2A fuses on the high street..? Am I being overly cautious, or is a 1A/2A fuse a sensible proposition..?

Ta!

Wal.

*EDIT 1A found on the High Street...

Wal
I don't think you can buy any smaller than 3A fuse for standard plug.

It will be fine a 100W lamp will only take about 0.5A so no prob with the switch.

edit make sure there is an earth wire to the lamp

Cheers Clive,

Yeah - the bulb won't be drawing any more than 0.5A - but if it malfunctions and ends up drawing a bigger current I'd rather have the fuse blow than the switch melt, if you get me. I saw some 1A fuses in a small electrical shop in Didsbury yesterday - he reckoned he could get 2A, was just out of stock at the time. As far as the earth cable goes - the lamp has a two-core L/N 3A flex - am I best off replacing this with a 3-core and securing the earth cable to the metal chassis of the lamp? ie. perhaps the bracket that holds the bayonet fitting..?

Wal.

Quote:

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Originally Posted by Wal

Cheers Clive,

Yeah - the bulb won't be drawing any more than 0.5A - but if it malfunctions and ends up drawing a bigger current I'd rather have the fuse blow than the switch melt, if you get me. I saw some 1A fuses in a small electrical shop in Didsbury yesterday - he reckoned he could get 2A, was just out of stock at the time. As far as the earth cable goes - the lamp has a two-core L/N 3A flex - am I best off replacing this with a 3-core and securing the earth cable to the metal chassis of the lamp? ie. perhaps the bracket that holds the bayonet fitting..?

Wal.

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Yes you need an earth cable to the lamp Just keep the 3A fuse they are different than the glass fuses I have never seen a smaller one fitted to a British 13A plug

>Yes you need an earth cable to the lamp Just keep the 3A fuse they are different than the glass fuses I have never seen a smaller one fitted to a British 13A plug

Okay - but it wasn't a glass fuse - it was a fuse for a household plug - like this: http://www.diy.com/departments/bq-1a.../177930_BQ.prd

I've seen 2A online, but not on the high street...

Wal.

Quote:

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Originally Posted by Wal

>Yes you need an earth cable to the lamp Just keep the 3A fuse they are different than the glass fuses I have never seen a smaller one fitted to a British 13A plug

Okay - but it wasn't a glass fuse - it was a fuse for a household plug - like this: http://www.diy.com/departments/bq-1a.../177930_BQ.prd

I've seen 2A online, but not on the high street...

Wal.

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Ok Wal you win:crushed: But I still would not use one as when a lamp is first lit it will draw a lot more current for a few m/seconds and might just blow a 1A fuse. But hey it is your decision

Heh - Clive - you know me, I know NUFFINK..!

I was just a bit confused as I'd have thought you'd want the fuse to blow before an unsuitably high current went further up the pipe... Dunno, maybe I'm just over-thinking it..!

Wal.

You are over thinking it.

While you are technically correct, even a 2A rated switch will more than likely survive switching a load that will blow a 3A fuse.
You've got to consider what kind of load that's likely to blow a 1A fuse, but not a 3A, and not be noticed in a basic lamp?
L&N would need to be shorted together in such a way that they only drew 2.5A, and what is the real possibility of that happening?

The far more likely fault, is L and/or N wires rub through on something earthed, in which case it should trip the RCD. Even if you don't have an RCD upstream of your sockets, you should notice a fault before it even gets to the point of blowing a 1A fuse.

For a standard uk BS1363 square 3 pin plug the fuse sizes are 3amp and 13amp. There used to be 5 amp but this was done away with a few years ago.
So for your lamp fit a 3 amp fuse that complies with BS1362.

one inch 1A , 2A, 3A 5A , 7A ,10 and 13A HRC (High Rupture Capacity) Fuses for the UK 13A plugs are available
but the range in the typical high street shop is very often limited to 3A, 5A & 13A

John

PS

https://www.tlc-direct.co.uk/Main_In...20plug%20fuses