Spændingsklasser

Spændingsklasser is a term used to describe categories of electrical equipment based on insulation and protective measures related to the maximum operating voltage they are designed to withstand. The concept helps ensure user safety, guides product design, and informs installation and maintenance practices. The classification is embedded in safety standards and labeling used across Europe and many other regions.

Spændingsklasse I refers to devices with basic insulation and a protective earth connection. In the event of insulation faults, the protective earth helps keep exposed conductive parts at a safe potential. Spændingsklasse II describes devices that use double insulation (or reinforced insulation) and do not require a protective earth connection; these devices provide an additional safety layer to protect users even if a fault occurs. Spændingsklasse III covers equipment designed to operate at safety extra-low voltage (SELV) and typically powered from low-voltage sources, reducing risk for users and often not requiring protective earthing.

In practice, a product’s spanningsklasse is indicated on its label or in its documentation and determines how it should be connected to power, what kind of protective measures are necessary in its environment, and what testing and compliance are required. The classification influences risk assessments, installation rules, and maintenance planning, and it is a key criterion in consumer safety and electrical compliance.

The concept originated from and is maintained through international and regional electrical safety standards. While the exact definitions can vary slightly by standard, the basic idea is to match insulation quality, earthing requirements, and voltage exposure to the level of risk associated with the device. See also electrical insulation, protective earth, SELV, PELV, and related safety standards.