This bi-directional wireless I/O system is designed to be deployed within a few hours and requires no software configuration. The 3-30 Vdc discrete module has four inputs and four outputs, while the analog modules have two inputs and two outputs. Several antenna combinations are available for use with the radio modules and have a range of up to 4 mi (900 MHz) and up to 1 mi (2.4 GHz). Each system can accommodate as many as 16 module pairs and feature a response time down to 100 ms.