OI type of appliances At least the basic insulation and grounding terminals of the appliance, power cord in the flexible cable without grounding wire, plug does not have a grounding pin, can not be inserted into the power socket with grounding. Currently, most domestic power washers produced in China are OI-type appliances.
O class appliances: 220v50hz TV, computer, etc. O1 class appliances: refrigerator, induction cooker, etc. Class II appliances: generally not suitable for indoor 220-volt electric motors driven by the motor, etc. III are generally 380-volt three-phase electricity driven appliances are suitable for large and medium-sized enterprises.
Extended information:
1. Class 0 equipment.
This refers to equipment that relies on basic insulation as protection against electric shock, and once the basic insulation fails, the safety of the equipment depends entirely on the surrounding environment. This requires such equipment to be used in a "well-insulated" environment. For example, wooden floors, wooden walls, dry surroundings and so on. This kind of very strict requirements for the use of environmental equipment, the scope of use is very limited.
2, Class I equipment.
This means that the protection of equipment against electric shock not only rely on basic insulation, but also need to be able to touch the conductive part of the facility fixed wiring and protection (ground) line connected. In this way, once the basic insulation fails, because the accessible conductive part has been connected to the grounding wire, so the safety of the user is guaranteed.
3, Class II equipment.
The protection of equipment against electric shock not only rely on basic insulation, but also additional insulation and other safety measures. Once the basic insulation failure, additional insulation can ensure the safety of users. If double insulation, itself is equivalent to the level of basic insulation plus additional insulation.
4, Class III equipment.
This means that the equipment is powered by a safe extra-low voltage. This type of equipment within the voltage can not be higher than the safety of the extra-low voltage. class III equipment is from the power supply side to ensure safety.
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