Case study of an open greenhouse control system built with Industrial Shields equipment. Two Arduino based M-Duino Ethernet PLCs read the climate sensors over an I2C bus with multiplexers, plus digital and analog sensors, and drive pumps, valves, ventilation and lights with a control sketch for each phase written in the Arduino IDE. A Panel PC with a built-in Raspberry Pi runs an MQTT broker and a Node-RED dashboard for remote control and out of range alerts.

The PDF covers the challenge, the control logic of humidity, CO2 and light, the system architecture with the signal list and the hardware used. Interactive version: greenhouse case study online.