IEC 61936-1:2021 is the international standard for Power installations exceeding 1 kV a.c. (Altern Current). In simple terms, it is the rulebook for high-voltage substations, switchgear, and the heavy industrial infrastructure that keeps the modern world running.
The "story" of this document is about the tension between two massive global forces:
IEC 61936-1:2021 represents a vital evolution in power system standards. By modernizing insulation coordination rules and integrating safety protocols for new types of switchgear and renewable energy sources, the standard ensures that electrical infrastructure remains safe and robust.
For engineers and project managers, compliance with this standard is not merely a regulatory hurdle but a fundamental engineering practice to mitigate risk, ensure longevity of assets, and protect human life.
Transformer fire separation walls must be 120 minutes fire-rated (REI 120). Oil containment pits require a capacity of at least 100% of the transformer oil volume.
The primary objective of IEC 61936-1:2021 is to ensure that power installations are designed and built to provide adequate safety for personnel and reliable operation under normal and fault conditions.
Key areas covered include:
General design requirements
Insulation coordination and overvoltages
Earthing (grounding) and equipotential bonding
Protection against electric shock
Short-circuit and fault studies
Overcurrent protection and coordination
Switching, control and protection devices
Cables and conductors
Busbars, busducts and switchgear
Indoor and outdoor installation specifics
Testing, commissioning and maintenance
Documentation
Standard for Common Rules for the Design and Erection of Electrical Power Installations
Date: October 2023 Subject: Power Systems Engineering, Safety Standards, Infrastructure Design