QEI

Computer and microprocessor based supervisory and data acquisition and automation hardware and software for monitoring and control of electric, transit, water and gas networks via remote terminal units and data concentrators and multifunction gateways; telemetry electronic circuits and electric switches comprised of plug-in modules containing switches and indicator lights to transmit or receive signals providing the status of events that is used to collect data or monitor or control certain processes, namely, frequency domain multiplexing and point status scanning and analog control and data transmission and audio tone signaling and digital signaling