Electrical – Do 240V AC switches only need to open the active wire

acappliancesmainssafetyswitches

I want to add a simple inline switch to a small, mains powered lamp (~240V AC, 10W Max).

It's earthed; it has a typical 3-core cable with a 3-pin plug.

I bought a bunch of switches, expecting each switch to have 2-3 contacts per side, but they only have 1 contact per side. In other words, they're only capable of breaking contact for a single wire. They have grooves down the adjacent sides to run/hold the other 2 wires, but it seemed strange.

Is it fine to just open the active wire, as shown below?
Note: Brown = Active. Blue = Neutral.

This is the kind of thing I do all the time with 6-24V DC applications, but domestic appliances aren't really in my wheelhouse. Is there any reason this would be inappropriate or unsafe with 240V AC?

Best Answer

In the USA only industrial devices have to disconnect neutral as well as the hot wire. For residential use normally only the hot wire is disconnected, as neutral normally has a low voltage on it less than 10 VAC, which is not a shock hazard. European and Canadian rules may vary about disconnecting neutral but typically follow the same UL/cUL/TUV regulations.