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Which wire goes where (emergency stop button)? Answered

I'm trying to wire up an emergency stop button.

Australian power outlets have 3 prongs, active, neutral and earth. My switch has 2 connections, one Normally Open one Normally Closed. 

I think I need to have the active line connected to NC (so connected when the switch is in the ON position) and the neutral connected to NO, and the earth remaining connected regardless.
This should mean that when it's on the Active line is connected to ground and this the power is on past the switch.
When the switch is OFF the neutral is connected to earth and it is safely off (any remaining power in devices connected to it can drain to earth).

Am I right in thinking this? or is there something I've overlooked?

I am also aware that mains power (240V AC in Australia) is deadly, and not a good idea to play with unless you are a qualified expert. I do intend to have this checked before use, however I would like to have a proper understanding before I go any further.

The emergency stop button I have is rated for sufficient volts and amps to use on Australian mains power, and is suitable for the intended use (before a corded drill or circular saw).



Best Answer 6 years ago

The switch should have three connection points: common, NO, and NC. You want the switch to be inline with the "hot" (i.e., active) wire between your outlet and your device. To do that, you cut the active wire, connect one side of your cut to the common and the other side to NC.

Then, when the device is plugged in, it will receive power normally. When you hit the stop button, power will be disconnected.