As a lifting equipment, electric hoists are essential protective devices. Today, Shanghai Yiying will introduce you to electric hoists for protecting electrical appliances.

　　1. Fuse: A fuse is a simple circuit protection device, whose principle is that when the current flowing through the fuse reaches or exceeds a fixed value for a certain period of time, its own melt melts and cuts off the circuit. Has: the current must reach a certain value, with many types, including delayed action, fast action, ultra fast action, etc; After the action, the body is damaged and cannot be reused, and must be replaced; Whether a fuse is blown can be determined by a fuse indicator or by the appearance of the melt.

　　2. Load switch: The load switch has a simple arc extinguishing device, and the arc extinguishing medium is generally air. It can connect and disconnect a certain amount of current and overcurrent, but cannot break short circuit current and cannot be used to cut short circuit faults. So it is absolutely not allowed to replace circuit breakers solely with load switches. The load switch is similar to the isolation switch, and both have obvious opening gaps, which can easily determine whether the circuit is in the on or off state.

　　3. Transformer: A transformer is a device that uses alternating electromagnetic fields to convert different voltage levels, and the voltage before and after the conversion does not change in frequency. According to its usage, it can be divided into many types, and we often use power transformers.