Andy Brown is fond of beers and he loves homebrewing. To automate the temperature control required for fermentation and conditioning process, he designed a process-controller based on Arduino processor that allows precise switching of three relays to control the heaters, fridge and fans that are the parts of the temperature controlling mechanism in his brew fridge. The controller also features a triac for phase-angle dimming that is helpful for proportional heater or fan control. The device connects to a host PC via USB.
Find details here.
Arduino Process Controller