Measuring, signalling, checking, and supervision apparatus and instruments, namely, passive infrared environmental sensors, light switches, power switches, electronic motion sensitive switches, shutter switches for cameras, keypads in the nature of electronic keypads for controlling access to a premises, infrared bridge in the nature of integrated circuit modules for use with infrared detectors, computer network bridges in the nature of internet bridges; apparatus and instruments for conducting, switching, transforming, accumulating, regulating or controlling electricity, namely, power switches, dimmers, electric accumulators