May 23, 2014 AT 8:00 am

Analog Metered Boiler Control Via Email and Image Processing #piday #raspberrypi @Raspberry_Pi

Analog Metered Boiler Control Via Email and Image Processing, from Seb:

One of  my problems was waiting for the water inside the boiler to heat so I can take a bath. After starting the boiler I had to wait 30 minutes in the summer and 1 hour in the winter for the water inside the boiler to reach the desired temperature(45 degrees Celsius). Having to wake in the morning an hour earlier to press the button of the boiler or getting home tired and having to wait the water to heat was a pain.

To get rid of this problem the idea came: make a device that could remotely start my boiler and stop it when the water is heated. So it was clear that I was going to need a Raspberry Pi. Being such a small powerful device the Raspberry Pi could use a webcam connected to it’s USB to watch the analog thermometer of the boiler, do some basic image processing, take decisions and stop the boiler. By sending an e-mail to the gmail address that I created for this I can now start or stop my boiler remote.

For this to work the Raspberry Pi runs 2 python scripts and a C++ program that uses the openCV library for image processing. A program written in C is the main daemon that starts the above mentioned python scripts and the image processing program, it takes decisions based on their output and starts/stops the boiler.

WARNING: The boiler is started using a GPIO pin on the Raspberry Pi that commands a relay. The relay is connected to an electrical socket that has the boiler plugged inside. The schematic is very simple but it involves working with mains voltages. As you know: WORKING WITH MAINS VOLTAGES CAN KILL YOU!!! and you should know what you are doing or request help from someone who knows….

Read more.

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Pasted Image 5 23 14 1 09 AM


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1 Comment

  1. I think an AC rated solid state relay (SSR) would be a better choice.

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