Illuminated switchplate adapter. (With “schematic”.)

I added this item to an electrical order just to see how they’d implemented it. The device is a clear plastic bezel that sits behind a typical UK lightswitch and has two wires that are connected across either the two wires of an ordinary single way switch or across the strappers of multi-way switches. When the switch is off the full open circuit mains voltage appears across it via the load, and the switch illuminator then takes a very small amount of current to light a neon or LED without passing enough to make the light glow (it may make LED lamps glow or CFLs flash intermittently.)
The idea is that the glowing frame helps you locate the switch in a dark room, while possibly acting as a low intensity night light too.

If I have to be completely honest, I was disappointed by the circuitry in this device. I know they are trying to save space, but the size of the resistor and spacing was actually a bit ungenerous. I’m not going to be installing this in my own house.

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