Note: The official English title is: “Generators connected to the low-voltage distribution network – Technical requirements for the connection to and parallel operation with low-voltage distribution networks.”
The standard requires a grid-disconnection relay (Netz- und Anlagenschutz - NA-Schutz) to monitor voltage and frequency. If the grid parameters go outside defined limits, the system must automatically disconnect.
is the German Application Rule published by the VDE (Association for Electrical, Electronic & Information Technologies). It defines the technical requirements for connecting and operating power generation systems (such as photovoltaic systems, CHP units, and wind turbines) in parallel with the public low-voltage electricity grid ($U_n \leq 1kV$).
This VDE application rule applies to newly connected generation plants and storage systems, as well as to the expansion or modification of existing ones. It is intended for systems up to 135 kW. For systems above this threshold or those connecting directly to the medium-voltage grid, a different standard, VDE-AR-N 4110, applies. vde-ar-n 4105 english pdf
Many engineering firms access these documents through standards management platforms like Nautos or IEEE Xplore. Compliance and Certification
Notes on versioning and validity
VDE-AR-N 4105:2018-11 (Note: Ensure you are purchasing the latest version, including any recent amendments or drafts). Note: The official English title is: “Generators connected
The VDE FNN periodically updates application rules to align with European Union network codes, such as the Requirements for Generators (RfG). When sourcing a VDE-AR-N 4105 English PDF, it is critical to verify the version year:
Generators connected to the low-voltage distribution network - Technical requirements for the connection and parallel operation with low-voltage distribution networks. The Certification Process for Manufacturers
A common search is for "vde-ar-n 4105 english pdf". While the official standard is published in German, an English translation exists. It is important to note that German is the legally binding version. The English version is a translation provided for convenience, and a standard disclaimer states: "In case of doubt the German version will be valid" . Therefore, any critical technical or legal interpretation must always be verified against the original German document. It defines the technical requirements for connecting and
The guide outlines technical minimum requirements to ensure safe grid integration and high power quality. Documents - VDE FNN
Application Rule for the Parallel Operation of Generation Systems on the Low-Voltage Network Date: October 26, 2023 Prepared for: System Planners and Electrical Engineers
As Germany's primary distributor for technical standards, Beuth ( dinmedia.de ) offers electronic access to VDE application rules translated into English.
After a grid failure, the system must wait for a stable grid (usually 60 seconds) before re-synchronizing. 2. Voltage and Frequency Stability