The standard applies to:
Operates continuously or temporarily alongside the main distribution grid. This mode allows local generation to supplement grid power or feed energy back into the utility network. 3. Isolated (Islanded) Operation
The standard mandates mechanical or electrical interlocking to prevent simultaneous connection of mains and generator outputs to the same load.
Ensuring the installation works as intended for its specific use. External Influence Resilience: iec 60364 part 551 pdf
: Supply to an installation as a switched alternative to the public utility distribution network during blackouts.
When a generator is running, it effectively becomes a new "source" for the installation. This impacts earthing and protection systems:
If you found this technical breakdown useful, please share it with your network. For the full PDF, please consult the IEC Webstore or your national standards body. When a generator is running, it effectively becomes
Thus, obtaining the current PDF is not just for today’s compliance – it prepares you for the evolution of distributed energy resources.
Protection devices must be rated to clear faults using the limited short-circuit current available from the generator. Protection Against Electric Shock
By obtaining and applying the genuine , you demonstrate professionalism and a commitment to safety. Do not rely on outdated or unauthorized copies. Invest in the standard, and it will protect your work—and your reputation. BS 7671 in the UK
Choosing the right IP (Ingress Protection) or IK (Impact Protection) ratings based on the "external influences" tables. Global Compliance:
: Residual current devices (RCDs) must be rated to avoid nuisance tripping from normal structural leakage paths while safely detecting low-level leakage from inverted DC or generator sources.
Many countries adopt IEC 60364 as a national standard (e.g., BS 7671 in the UK, HD 60364 in Europe, AS/NZS 3000 in Australia). Clause 551 is often reproduced verbatim. Purchasing from your national body may be cheaper and includes local amendments.