Are my devices in good condition? How good is the mains supply quality? Are there any consumers which are causing high power costs and should be replaced? Be it for private use or as measured value monitors in building management, these devices deliver quick and uncomplicated answers to these questions and others like them. Simple variants are inserted between the socket and consumer. Connected power rating and consumption – even measured over a 24-hour period – can be read from the display. Higher-performance power metering devices are suitable for instance also for systems operating on DC or three-phase AC, and can be used to determine balance across the three phases, reactive power and phase angles. Multi-functional mains power analysers are additionally capable of integration into existing Ethernet-based communications networks, and in some cases can deliver graphical evaluations.