Toasters..

[jamesy boy]

They only let you lower the rack-bit (technical term) when the toaster is plugged in and the socket is switched on.

How?

[Mortartube]

I believe that the arm is held down by an electromagnet which switches off when the thermostat cuts out when the toast is done. No power = no magnetic force.

[gammaray]

Your tefal toaster has by far an away a more complex method of controlling the burn time of the elements (plenty of techno speak here!!) a simple toaster using a simple timer and electomagnetics as Mortartube explains will only work when current passes through it.

[jamesy boy]

in a pickle, I don't do it on purpose, I do it without realising the toaster is unplugged, and spend a couple of minutes thinking the mechanism is knackered, before realising that my wife has plugged her phone charger in.