Insulation tools are divided into I, II and III categories according to their different insulation structures.
Class I tools refer to power tools with ordinary basic insulation. The protection against electric shock not only relies on the basic insulation of ramie, but also should add a safety precaution, that is, the exposed conductive part of the body that is not charged under normal conditions but becomes a charged body when its basic insulation is damaged is protected and connected to zero. In order to be reliable, there should be no less than two protective zeroes, and additional leakage protection should be added. At the same time, the operator is required to use insulating protective equipment.
Class II tools refer to electric tools with double insulation or reinforced insulation. In terms of protection against electric shock, they not only rely on their basic insulation, but also have their live parts under normal conditions and accessible non-charged conductive parts. Double insulation or Strengthening insulation and isolation measures is equivalent to designing and manufacturing the operator's personal insulating protective equipment on the tool in a reliable and effective way.
Class III tools refer to electric tools powered by safety extra-low voltage, and rely on safety isolation transformers for power supply in terms of protection against electric shock.
