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 SF Innovations - Innovators in Electronics

Mains Switch Widget for the Raspberry Pi and Arduino

(Mains Switch Relay 2 + Enclosure for MSR2)


The Mains Switch Widget allows the user to switch 230V or 110V mains ON and OFF to mains powered devices from micro-controllers like the PIC and the Arduino or from single board computers like the Raspberry Pi and the Beaglebone. All the safety requirements are designed-in to prevent any faults resulting in a fire.


A plastic enclosure is available to prevent the user from accidentally touching the mains voltage. The user has to supply and wire in a suitable mains extension cable.


* Electrical isolation (4kV) between the control side and the mains voltage

* Protected by a 5A fuse in the product - to protect the PCB tracks from overheating if there is a fault with the load

* Cable ties to prevent the mains cable pulling out

* Protective enclosure to prevent accidental contact with mains voltage

* LED indication of ON and OFF states

* Can be configured for most parts of the world by using a suitable mains extension lead (not supplied)


Mains Switch Widget - Applications


There are many applications that require switching mains powered appliances ON and OFF. Here are some examples.


Maintaining an environment at a constant temperature:

A temperature measuring device and the Mains Switch Widget with a heater could be used in a feedback control system to maintain a constant temperature.


Keeping a water tank topped up:

A water level detector can be used to control a pump using the Mains Switch Widget to maintain constant water level in a tank.


As a module in a Home Automation system:

A Raspberry Pi could be used to switch lights, heating and ventilation using this product. With a browser interface, this could be controlled from anywhere in the world.  



Mains Switch Relay 2

Ready Built PCB assembly



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Enclosure for

Mains Switch Relay 2


Mains Switch Relay 2


User Instructions



Enclosure for


User Instructions



Mains Switch Widget =

Mains Switch Relay 2


Enclosure for MSR2


£18 from this site


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