What Is Class II Electrical Equipment?

Class II equipment is designed so that protection against electric shock does not rely solely on basic insulation or a protective earth connection. Additional safety is provided through double or reinforced insulation.

This type of equipment is commonly referred to as double insulated equipment.

When Is the Double Insulated Symbol Used?

The square-within-a-square symbol identifies electrical equipment classified as Class II. It indicates that the equipment uses the required insulation measures for Class II construction and does not rely on a protective earth connection for protection against electric shock.

The symbol should only be used when the product has actually been designed and assessed as Class II equipment.

Does Class II Equipment Need an Earth Connection?

Class II equipment does not rely on protective earthing for protection against electric shock. It should therefore not be confused with Class I equipment, which typically uses a protective earth connection as part of its safety measures.

A functional earth connection may still exist in some equipment for purposes unrelated to protection against electric shock.

You Might Also Need These Symbols

For other electrical constructions, see the Protective Earth and Functional Earth symbols. Depending on the product and market, electrical equipment may also require a CE or UKCA mark and the WEEE crossed-out wheeled bin.

Download

Download the Class II double insulated symbol below in SVG, PNG and PDF format.

Class-2-appliance-symbol.pngClass-2-appliance-symbol.svgClass-2-appliance-symbol.pdf

Use this symbol only for equipment that meets the applicable requirements for Class II construction. Do not use it merely because a product does not have an earth connection.

Looking for another electrical marking? View all electronics symbols.