The basic Pick-to-Light system includes a personal computer, a controller, pick tags, bay indicators, Order displayers and completion indicators. It is designed as compact, reliable, versatile, easily maintained and installed module to satisfy diversified applications. The picking system computer acquires the picking data from warehouse management system via on-line or off-line medium, and sends to pick tags. Pickers pick up the items by quantity shown on the tags and return picking status back to the system.

Modbus is an industry adopted communication protocol based on RTU, ASCII,and TCP protocols for various applications.