Classification of Class I, Class II and Class III tools:
A class of electrical equipment will be damaged or injured after accidental power failure or shutdown. A class of equipment refers to equipment with good technical performance, stable operating conditions, complete technical data and drawings, and can ensure long-term safe operation. Such as transformers, disconnectors, circuit breakers, transformers and so on.
Class II electrical equipment will be damaged after power failure or shutdown. Class II equipment refers to equipment whose technical performance has declined, and its operating conditions can basically meet the operating requirements, with general defects, but it does not affect the long-term safe operation, and the main technical data and drawings are complete. Such as electric meters, protective relays, communication equipment and so on.
Class III electrical appliances are those with ultra-low voltage protection, and the operating voltage is not more than 36V, if they will not be damaged or injured after the power failure or shutdown of Class III equipment.
Extended data:
Operating regulations of angle grinder:
1, with protective eye mask.
2. After turning on the switch, wait for 3 ~ 5 minutes, and observe that the grinding wheel rotates stably before it can work.
3. Workers with long hair must tie up their hair first.
4. The cutting direction cannot be towards people.
5. Stop for fifteen minutes after working continuously for half an hour.
6. You can't catch small parts by hand to process the angle grinder.
7. Consciously clean the working environment after the work is completed.
Baidu encyclopedia-angle grinder
Baidu encyclopedia-second class electrics