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The Raspberry Pi - monitor and control

The  picture accompanying this article portrays a Raspberry Pi model 3B SOC(system on a  card).

The Pi is a full fledged computer with wi-fi and bluetooth capabilities. The card also has an HDMI connector for using a TV as a computer monitor.

   There are four USB connectors to accommodate external devices. The computer uses a SD memory  card for memory, similar to a hard drive in a standard size computer.
   The software is a semi-proprietary operating system derived from Debian Linux and is called Raspbian Jessie. The card is a popular training environment for young people.
   In this context, the card is used to monitor and control the solar panel array. Scripts in PHP and Python languages read analog-to-digital converters connected to panels and get voltage and current measurements. These allow tracking of power output, power usage, and sun location.
   Data is deposited in text files in csv format for use with spreadsheets. This is also useful for making charts of daily solar activity. There are other options for data manipulation. The D3 javascript library can create web (HTML) pages of the tabulated data and save the files to disk. SVG images can also be created and saved.
   The image shows the pin functions for the Pi.
   The Pi can issue commands to control a linear actuator which can adjust the position of the array with respect to the sun.

Posted 3 weeks ago by Jim Julian