Appendable device and system for data acquisition, analysis and control

Each device includes a processor 16, memory 18, an input/output interface 20 and power source 22 in a housing which is adapted for mounting to a surface. A transceiver 14 and antenna 24 may also be included. Each of the devices can communicate with one or more sensors and or control outputs. A plurality of the devices are adapted to interoperate with each other and/or a workstation to monitor and/or control a process. Communication between devices may be by a wireless link or by a hard-wired communication technique such as the internet.