Lecture 4: Device Standards

Question 1

Standard definition

Answer 1

A Standard is a published document which sets out specifications and procedures designed to ensure that a material, product, method or service is fit for its purpose and consistently performs the way it was intended to

Question 2

Class I equipment

Answer 2

equipment that provides a means for connecting the equipment to the protective earth conductor

Question 3

Class II equipment

Answer 3

equipment in which protection against electric shock does not rely on basic insulation only, but in which additional safety precautions such as
double insulation or reinforced insulation are provided, there being no provision for protective earthing or reliance upon installation conditions

Question 4

Class III equipment

Answer 4

equipment in which protection against electric shock relies on supply at safety extra‐low voltage and in which voltages higher than those of
safety extra‐low voltage are not generated.