Bathroom sink light/shaver socket fixture

[Tim Streater]

The one we have fitted now in our bathroom I use for electric toothbrush charging rather than a shaver. It is similar to this one (but is not this unit):

The unit I have I got because the shaver socket is always on, rather than only being on when the light is on. It's now 8.5 years old, and I notice that one end is permanently quite warm. Not hot enough to scorch the plastic, but hotter than I would expect a unit to be with the light off and no load (I unplugged the TB charger this morning).

Would one expect the sort of isolation transformer these units have to generate any heat? Or have I been effectively mis-using it by having the TB charger permanently plugged in.?

[Dave Plowman (News)]

IIRC, most have some form of switch that is operated by the plug pins. So the transformer is off with nothing plugged in. For it not to get warm when powered up would need zero impedance. I doubt it has.

FWIW, I fitted a couple of 13 amp sockets in the airing cupboard for charging bathroom things. If only for tidiness. ;-)

[Andy Burns]

Possibly, the newer MK models are now designed for (continual charging of) toothbrushes as well as (intermittent use of) shavers

the older ones said "shavers only"

[Andrew Gabriel]

It will be permanently on if you leave a charger plugged in to it. Most of these isolating transformers use the socket shutter as a switch on the primary side.

One slight warning is the voltage regulation of these transformers is not great. Off-load, they are permitted to output up to 270VAC. A charger is very low current draw, and almost off-load. If the charger has a wide ranging voltage input down to 120V, plug it in to the 120V socket rather than the 240V socket, and the charger might last longer.

[Dave Plowman (News)]

Think that was to tell foreign visitors not to use it with something taking more current? Assuming they spoke English, of course. ;-)

[Tim Streater]

Hmm, yes. I should probably look at replacing it. TMH did it last time, perhaps I could manage it myself.

[Brian Gaff]

I'd not expect it to get hot, warm maybe, but these things are supposed to sustain shaver chargers so I do not think its much of an ask to charge up a toothbrush. If its not getting too hot to touch, normally its fine. Often the complaint is a constant buzzing from these things when the glue inside starts to give up the ghost and it rattles. That in itself can generate heat. I'd have thought that if anything was wrong like shorting turns it would have blown something by now. Brian

[Scott]

Is there no merit in the argument that under-loading pushes up the voltage?