What type of switch is this?

[CC07 PEU]

I'd like to replace a faulty switch from my desk lamp and I don't know what type of switch I need to be searching for as a replacement.

The old switch is a rotational three way i.e. so that the two lamps can either be on one at a time, both can be on, or the lamp can be off.

The switch I extracted from the old lamp is pictured below but what should I be asking for?

It was riveted and I had to break it to get the wires out. It says on the switch 6A 125 VAC if that makes any difference. Any help appreciated:

[miniman]

I think the problem you'll have is that it's something that's much more common in the USA - most desk / table lamps, especially in hotels, seem to have them.

Here's something similar:

http://gb.mouser.com/ProductDetail/ALPS/SRBM131300...

I couldn't find an equivalent from the normal UK suppliers (RS / Farnell, Maplin etc.)

[bimsb6]

Wow that penny is huge !

[minicab]

It's a three position rotary switch.... 6A/125VAC is the rating.

This kind of thing - although this is a 2 position http://www.sourceresearch.com/Store1/quickstore.cf...

[motco]

Should you be using a switch rated at 125Vac on 230Vac?

[JM]

motco said:

Should you be using a switch rated at 125Vac on 230Vac?

It's more the amps and watts he'd need to worry about.

[motco]

JM said:

motco said:

Should you be using a switch rated at 125Vac on 230Vac?

It's more the amps and watts he'd need to worry about.

So you wouldn't think that arcing gaps are less on 125Vac switches?

[Simpo Two]

Is 6A at 125V the same load as 3A at 250V?

[Ganglandboss]

Simpo Two said:

Is 6A at 125V the same load as 3A at 250V?

Both are 750W of power but the strain on the conductors will be greater at lower voltage because the current is higher. That is the reason extra low voltage lighting needs bigger cables and why power is distributed at high voltage.

[hairyben]

Ganglandboss said:

Both are 750W of power but the strain on the conductors will be greater at lower voltage because the current is higher. That is the reason extra low voltage lighting needs bigger cables and why power is distributed at high voltage.

Theoretically, a switch built for 250v will need to snap into place quicker to reduce arcing, which will be more of an issue at the higher voltage. In practice the biggest concern would be the standard of the insulation between live terminals and one's fingers will differ. You simply shouldn't use parts at higher than their rated insulation, in the same way you wouldn't inflate a tyre rated at max 50psi to 100psi.

For old parts like that you could try the hobbyist scene- people who like/restore old radio sets and suchlike junk? they must have forums, who might lead you to specialist suppliers?

[miniman]

hairyben said:

Theoretically, a switch built for 250v will need to snap into place quicker to reduce arcing, which will be more of an issue at the higher voltage. In practice the biggest concern would be the standard of the insulation between live terminals and one's fingers will differ. You simply shouldn't use parts at higher than their rated insulation, in the same way you wouldn't inflate a tyre rated at max 50psi to 100psi.

For old parts like that you could try the hobbyist scene- people who like/restore old radio sets and suchlike junk? they must have forums, who might lead you to specialist suppliers?

True, but at the voltages and currents we're talking about here it's not going to be critical. In fact, if you look at the link above, the switch in question is rated for both 115V and 230V with the appropriate change in current rating.