http://info.opto22.com/raspberry-pi-io
Starter kit: http://info.opto22.com/raspberry-pi-io
With Opto 22's Digital I/O System for Raspberry Pi, you can switch real-world electrical loads like industrial motors and pumps, and sense circuits and status through industrial-grade sensors, with your Raspberry Pi's GPIO.
Use your favorite Pi-supported programming language like Python, C, and more. Or, use Node-RED to quickly read and write I/O with these Pi build instructions.
For more information, including details about selecting your own racks and I/O modules, see our Selection Guide for Industrial Digital I/O for Raspberry Pi.