Can I Do This? Power smart switch with no neutral.

[Mikesd]

I've Seen this question asked and answered dozens of times. But never like this.

I have a switch that requires a neutral. I do NOT actually have to switch AC power. Yes switch was designed to switch ACc but it's not nnessary for my case.

My switch is just going to communicate over wifi to be used just to turn on/off my wifi controlled devces. So, can I just take an extension cord and plug it into a 3 pronged (US) sockets and use the line, neutral, and ground to power my switch. I dont need it mounted to the wall like a light switch. I assume the neutral in the socket is what my switch requires.

Will that work?

 

[Avo Mk8]

You can do this, but it would be advisable to put a fuse in the circuit prior to your smart switch, as they are not designed to switch all the current available from a socket.
The switch will only switch mains power, ie give you mains voltage to power your devices. It will not normally have 'volt free' contacts to switch other circuits, although you could connect a relay to it, if that's what you need.

The smart switch will only support the current of the light bulb it is designed to power, so you need to be careful not to overload it with 'devices'.

You can purchase smart switch devices designed to switch mains power rather than lights, which might be more suitable, eg: https://www.amazon.com/BN-LINK-Monitoring-Function-Compatible-Assistant/dp/B07CX5KLXN/ref=sr_1_29

But I have to ask, if you have wi-fi devices, why do you need another wi-fi device to switch them!?

 

[Mikesd]

You can do this, but it would be advisable to put a fuse in the circuit prior to your smart switch, as they are not designed to switch all the current available from a socket.
The switch will only switch mains power, ie give you mains voltage to power your devices. It will not normally have 'volt free' contacts to switch other circuits, although you could connect a relay to it, if that's what you need.

The smart switch will only support the current of the light bulb it is designed to power, so you need to be careful not to overload it with 'devices'.

You can purchase smart switch devices designed to switch mains power rather than lights, which might be more suitable, eg: https://www.amazon.com/BN-LINK-Monitoring-Function-Compatible-Assistant/dp/B07CX5KLXN/ref=sr_1_29

But I have to ask, if you have wi-fi devices, why do you need another wi-fi device to switch them!?

You can do this, but it would be advisable to put a fuse in the circuit prior to your smart switch, as they are not designed to switch all the current available from a socket.
The switch will only switch mains power, ie give you mains voltage to power your devices. It will not normally have 'volt free' contacts to switch other circuits, although you could connect a relay to it, if that's what you need.

The smart switch will only support the current of the light bulb it is designed to power, so you need to be careful not to overload it with 'devices'.

You can purchase smart switch devices designed to switch mains power rather than lights, which might be more suitable, eg: https://www.amazon.com/BN-LINK-Monitoring-Function-Compatible-Assistant/dp/B07CX5KLXN/ref=sr_1_29

But I have to ask, if you have wi-fi devices, why do you need another wi-fi device to switch them!?

In my case, I don't have to switch AC at all. I'm only using it to power my switch.

The reason I'm using this switch is I have many other wifi devices. I haven't found a way to switch them all on or all off with a single switch. I may be able to find a way though.

It's for a security system I'm putting together. I have a dozen cameras. And half dozen wifi switches. I could use my smart phone to setup rules and switch them that way but that still takes a number of actions. But my wife is clueless about technology. A simple switch allows her to turn everything on or off with a single switch.

 

[Avo Mk8]

i'm not quite clear how you would want to switch off the security system as a whole - could you explain?
will you be switching off a low voltage supply, or could you switch off the mains feed to everything?

High Power Mains Switching with Sonoff - Scargill's Tech Blog

I am as most of you know a great fan of the Sonoff BASIC modules – because, in the main, they are cheap and reliable – but increasingly I’ve been faced with challenges that involve the need for isolated contacts – or high power (immersion heating) or both. Well, here…Read More→

tech.scargill.net

Or do you want to put a separate module on each security device and collectively address them all to switch everything at once (in which case is this switching mains or something else?)

You can buy wi-fi relays/ switches that do pretty well anything these days, either as enclosed modules, or as pcb's to rig up in an enclosure. They can control mains loads or operate relays, or have isolated contacts. I don't think you need to use a "light switch" unless you have a particular app in mind.

https://www.amazon.com/MHCOZY-Channel-Wireless-Switch-Control/dp/B095X3J81J/ref=sr_1_21

 

[Mikesd]

i'm not quite clear how you would want to switch off the security system as a whole - could you explain?
will you be switching off a low voltage supply, or could you switch off the mains feed to everything?

High Power Mains Switching with Sonoff - Scargill's Tech Blog

I am as most of you know a great fan of the Sonoff BASIC modules – because, in the main, they are cheap and reliable – but increasingly I’ve been faced with challenges that involve the need for isolated contacts – or high power (immersion heating) or both. Well, here…Read More→

tech.scargill.net

Or do you want to put a separate module on each security device and collectively address them all to switch everything at once (in which case is this switching mains or something else?)

You can buy wi-fi relays/ switches that do pretty well anything these days, either as enclosed modules, or as pcb's to rig up in an enclosure. They can control mains loads or operate relays, or have isolated contacts. I don't think you need to use a "light switch" unless you have a particular app in mind.

https://www.amazon.com/MHCOZY-Channel-Wireless-Switch-Control/dp/B095X3J81J/ref=sr_1_21

It really doesn't matter how I plan to do it since all I'm looking for is an answer to my original question. I'm not trying to learn a different way. I have all the hardware already.

But I will explain regardless.

1) For the most part, all I will be doing is turning OFF the cameras. My wife is paranoid about possibility of someone seeing us in the house.

2) She's non technical and doesn't want to learn how to do it by app or software

3) I want a single switch solution. I already have a switch that's Iompatible with my system. Originally I was going to replace a switch that controls a single recepticle we don't use, to power my switch. But the switch box has no neutral.

4) I can plug a power cord into the socket, and use the line and neutral to power my switch. No AC switching will be done. I'm just using the line and neutral to power my switch.

5) then make a rule that when my switch is on, all wifi cameras get turned ON. When off, another rule turns them all OFF.

6) I have an app that already does that, but like I said, my wife is not technical and doesn't want to learn. She would have to turn on phone, launch app, navigate to the shortcut buttons, figure out which one turns the camera off, press that button. Apparently that's too much technology for her.

The simple single switch solution does the same thing.

Mike

 

[Avo Mk8]

It really doesn't matter how I plan to do it since all I'm looking for is an answer to my original question. I'm not trying to learn a different way. I have all the hardware already.

But I will explain regardless.

1) For the most part, all I will be doing is turning OFF the cameras. My wife is paranoid about possibility of someone seeing us in the house.

2) She's non technical and doesn't want to learn how to do it by app or software

3) I want a single switch solution. I already have a switch that's Iompatible with my system. Originally I was going to replace a switch that controls a single recepticle we don't use, to power my switch. But the switch box has no neutral.

4) I can plug a power cord into the socket, and use the line and neutral to power my switch. No AC switching will be done. I'm just using the line and neutral to power my switch.

5) then make a rule that when my switch is on, all wifi cameras get turned ON. When off, another rule turns them all OFF.

6) I have an app that already does that, but like I said, my wife is not technical and doesn't want to learn. She would have to turn on phone, launch app, navigate to the shortcut buttons, figure out which one turns the camera off, press that button. Apparently that's too much technology for her.

The simple single switch solution does the same thing.

Mike

Ok.
Now I understand the question. Sorry I didn't get it before.
Yes, you can do exactly what you originally asked, ie power the switch from an outlet (or whatever) but not connect the switched output of it to anything. Just use the wi-fi response for what you need.
That is assuming the app or ifttt program you use is not going to ask for confirmation from the switch that it has actually switched a load!
Best wishes for the project.