DIN EN 50549-1:2026-01

This document applies to generating plants up to and including Type B that are operated on a low voltage distribution network. It specifies technical requirements in order to ensure that such plants operate in a manner that is compatible with the network. Essential requirements include protective functions - such as voltage and frequency monitoring, islanding detection, and behavior during network disturbances (for example, Fault Ride Through (FRT) and ROCOF withstand capability) as well as control behavior, such as frequency-dependent active power output. Communication with the network operator includes, for example, telecontrol engineering, controllability, and immunity to network events such as phase shifts. This document does not apply to plants that are not operated in parallel with the network (such as isolated plants), generating plants connected only to the medium voltage network - for which EN 50549-2 applies - or plants that fall under the network connection rules for Types C and D (for example, large wind farms or ground-mounted PV systems with direct medium voltage connection). The standard differs from DIN EN 50549-1 (VDE 0124-549-1):2020-10 as follows: a) a requirement for immunity to phase shifts has been introduced; b) the requirement with regard to ROCOF immunity for synchronous and non-synchronous generation technology has been harmonized; c) FRT for Type A has been changed from a recommendation to a requirement; d) further details have been specified for EESS in the event of overfrequency. Typical application examples include photovoltaic systems on residential or commercial buildings, battery storage systems with network connection, combined heat and power (CHP) plants in the low voltage network, small wind turbines or micro-gas turbines, and hybrid power stations with PV and storage.