urgent help! is there such a "one-push-button" for on and off switch for 240V?

Thread Starter

drew1900

Joined Jul 5, 2020
5
urgent help! is there such a "one-push-button" for on and off switch for 240V?

Meaning to say, i can press the same button to turn ON the device, and the same button to turn OFF the device? And also, when the power supply is cut and re-powered back, the device must be in turn OFF mode whether prior before that it was turn ON or OFF (due to safety reasons for my setup)

I saw youtube that there were a lot of DIY tutorials to make the circuit. But is there such a circuit (the push button) available to readily buy off the shelf in the market?

Any inputs will be greatly appreciated.

Andrew
 

SamR

Joined Mar 19, 2019
2,809
Short answer, maybe. Long answer, yes, you can build a low voltage control circuit to switch a relay or power MOSFET on/off.
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MisterBill2

Joined Jan 23, 2018
7,320
There are switches available with alternate function, push on / push off, and while they are used for some functions they are inherently unsafe because they mostly do not indicate if they are on or off.
The added safety requirement of default to off after power removal makes it more complicated, but a bit safer.
WHAT is wrong with the standard 2 button system?
I do not believe that OSHA even allows switches that are alternate action devices even if they indicate off and ON.
 

Thread Starter

drew1900

Joined Jul 5, 2020
5
There are switches available with alternate function, push on / push off, and while they are used for some functions they are inherently unsafe because they mostly do not indicate if they are on or off.
The added safety requirement of default to off after power removal makes it more complicated, but a bit safer.
WHAT is wrong with the standard 2 button system?
I do not believe that OSHA even allows switches that are alternate action devices even if they indicate off and ON.
hi, what is exact the standard 2 button system? the simple ON-OFF switch cutting off the LIVE wire right?
The thing that I need, is to have my device to remail power off, when my main MCB is power down and power back. Its for a rental studio, where I need the user (the customer) to turn on that particular device manually, (its a little complicated why I need to do that, but in short, its to allow the user to turn the device ON (which is a audio mixer), only after he or she brings down the master audio fader, which will prevent speaker popping and his ears as well...
 

Thread Starter

drew1900

Joined Jul 5, 2020
5
maybe I can suggest another easier alternative, is there a way whereby.... it can be just one switch, (or a knob, or a button, doesn't matter what type), and basically that switch will be reset back to 'OFF' when the main power supply is cut. And when the main power supply is back again, the user will only have to push the switch to 'ON' button in order to turn the device on. I don't require the user to turn the device off in any ways, the device will only turn off when we cut the main power supply.
 

MaxHeadRoom

Joined Jul 18, 2013
21,636
There are switches available with alternate function, push on / push off, and while they are used for some functions they are inherently unsafe because they mostly do not indicate if they are on or off.
Although the Schneider ones I use have a small shroud around the P.B. when the button is pressed, it is flush with the shroud, on push-off it stands proud of or higher than the shield.
IOW, the condition is visible.
If requiring an off condition automatically, it could be done with a small relay.
I also have a flip-flop relay circuit that uses one button and automatically reverts off with removal of power.
Max.
 

MisterBill2

Joined Jan 23, 2018
7,320
Although the Schneider ones I use have a small shroud around the P.B. when the button is pressed, it is flush with the shroud, on push-off it stands proud of or higher than the shield.
IOW, the condition is visible.
If requiring an off condition automatically, it could be done with a small relay.
I also have a flip-flop relay circuit that uses one button and automatically reverts off with removal of power.
Max.
OK, Max is correct about one brand of switch and one model. But the ones at most hardware and Home improvement stores are not like that. Schneider stuff is mostly a better quality.
For a one button ON/OFF function you would need a relay with a time delay "OFF" function. Press and release immediately and it is latched on, press and hold until the 3 second delay passes and it is released . And if the power goes off while it is on, it releases and does not reset when the power returns. But if you do use that circuit there must also be an indicator that the device is ON when it is on.
 

SamR

Joined Mar 19, 2019
2,809
It is really really bad form to leave unused CMOS inputs unconnected
I agree and I don't. I just threw a quick typical out that does what he wants. I also did not show how to do the output for his case. There are some things that you expect to be understood.
 

MisterBill2

Joined Jan 23, 2018
7,320
I agree and I don't. I just threw a quick typical out that does what he wants. I also did not show how to do the output for his case. There are some things that you expect to be understood.
All it takes is a mains powered time delay relay with a release after time timer. No CMOS and no low voltage circuitry driving FETs to interface with mains power. AB makes one that has an open after time contact. The implementation does take a pushbutton with multiple circuits, on NO and one NC
 

MaxHeadRoom

Joined Jul 18, 2013
21,636
OK, Max is correct about one brand of switch and one model. But the ones at most hardware and Home improvement stores are not like that. Schneider stuff is mostly a better quality.
For a one button ON/OFF function you would need a relay with a time delay "OFF" function. Press and release immediately and it is latched on, press and hold until the 3 second delay passes and it is released . And if the power goes off while it is on, it releases and does not reset when the power returns. But if you do use that circuit there must also be an indicator that the device is ON when it is on.
My circuit is just a simple 2 relay flip flop with single P.B. the relay's toggle with each consecutive push.
No time delay as such, resets to off on power off, optional indicator if needed.
A couple of diodes an R and a C.
The only issue for the OP is it is designed around 24vdc, typically.
Max.
 
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MisterBill2

Joined Jan 23, 2018
7,320
The TS response so very critical of the two button approach did not realize that it does provide the default to off function after any power interruption. And it should be possible to implement that with a single multi-contact button, so that a partial push switches off while a full press switches on. OR possibly the reverse, partly in for ON and a full-depth press for off.
 

Ramussons

Joined May 3, 2013
890
urgent help! is there such a "one-push-button" for on and off switch for 240V?

Meaning to say, i can press the same button to turn ON the device, and the same button to turn OFF the device? And also, when the power supply is cut and re-powered back, the device must be in turn OFF mode whether prior before that it was turn ON or OFF (due to safety reasons for my setup)

I saw youtube that there were a lot of DIY tutorials to make the circuit. But is there such a circuit (the push button) available to readily buy off the shelf in the market?

Any inputs will be greatly appreciated.

Andrew
Are you looking for something like this? Press once ON, press again, OFF.
https://picclick.co.uk/Push-button-switch-for-table-lamps-161858798613.html
 
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