SF Innovations

Modules for the Raspberry Pi and Home Automation

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Custard Pi range of accessories for the Raspberry Pi

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Mains Switch Relay

Mains Switch Relay for the Raspberry Pi and Arduino


The Mains Switch Relay is supplied ready built and tested without an enclosure. It is for use by competent persons in a suitable enclosure. This device 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.


* Electrical isolation between the control side and the mains voltage - the tracks are kept separate on the PCB

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

* LED indication of ON and OFF states

* Detachable input connector

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


Mains Switch Relay - 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 - User Instructions



Mains Switch Relay

Ready Built PCB assembly



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