Heat recovery ventilators and energy recovery ventilators - Testing and calculating methods for performance factor - Part 3: Annual sensible heating and cooling recovery performance factor of heat recovery ventilators (HRVs)

Power capacitors - Low-voltage power factor correction banks (IEC 33/589/CDV:2016); German version prEN 61921:2016

Electrical measuring transducers for converting AC and DC electrical quantities to analogue or digital signals (IEC 85/921/FDIS:2024); German and English version FprEN IEC 60688:2024