Why is Class II electrical equipment not required to be connected to a protective earthing conductor?

Class II electrical equipment is designed with safety features that provide an additional layer of protection against electric shock. The defining characteristic of this type of equipment is its supplementary insulation, which is intended to protect users from electric shock even in the event of a failure in the primary insulation. This extra layer of insulation effectively prevents any live conductors from becoming exposed, thereby significantly reducing the risk of electric shock to the user.

This construction means that Class II equipment does not require connection to a protective earthing conductor, since the design itself mitigates the risks that grounding typically aims to counteract. By relying on robust insulation rather than grounding, Class II appliances can operate safely without a direct earth connection.