Automatic 2 second 240v mains interruption using relays - how?

Tom Smith's picture


Joined: Feb 09, 2020

Replies: 0
Automatic 2 second 240v mains interruption using relays - how?
February 9, 2020 - 5:36pm

Hi guys and gals

Absolute beginner here doing a small project at home. I require the following functionality for an aspect of my project:-

Constant power to a device at all times (240v supply) with a momentary button that disconnects the supply circuit for 2 seconds and restores it automatically.

I was thinking a normally closed relay that when triggered, opens, stays open for 2 seconds, then closes again. How can I achieve this?  It needs to be 1 button press with the 2 second hold and then the close happening automatically in a sequence. Not sure if I require 2 relays with delays to achieve this and how I'd wire it up, or wether there's an off the shelf solution? Any help greatly appreciated. 

Many thanks in advance


Debasis Parida's picture


Joined: Aug 22, 2019

Replies: 72
for this you can use 555 timer
February 9, 2020 - 7:13pm

Hi Tom, for this you can use a 555 timer circuit along with a relay.When you push the button that activates the 555 timer which will trigger the relay.After a certain time, it will again restored.Hope it helps!!!

Sourav Gupta's picture


Joined: Feb 12, 2018

Replies: 100
You can also use RC time
February 11, 2020 - 9:59am

You can also use RC time constant and a transistor to achieve this one.