Scientific, electrical and electronic apparatus, instruments and devices; electrical, electronic and optical measuring, signalling and monitoring apparatus, instruments and devices; electrical and electronic devices for analytics; electrical and electronic devices for power analytics; apparatus, instruments and devices for detecting, measuring, analysing and recording electrical signals; apparatus and instruments for detecting, measuring, analysing and recording power signals; apparatus and instruments for detecting, measuring, analysing and recording electrical noise; electric power analysers; calibration apparatus, instruments and devices;