Views:1 Author:Site Editor Publish Time: 2021-04-07 Origin:Site
Electric hoists are mainly used in light and small lifting equipment and electric single-beam (suspension) cranes. There are wire rope electric hoists and electric chain hoists. The power distribution system of the electric hoist is as follows:
The power distribution system is provided by an explosion-proof electric control box. The power distribution system main circuit breaker, main power contactor, total overcurrent relay and automatic switches of various mechanisms constitute a subsystem, so that the branch circuit that has failed can be isolated for maintenance. Affect the operation of other branches and reduce the fault to a small range. The explosion-proof button is equipped with the start, stop, emergency stop switch and explosion-proof limit switch of the power supply of the whole machine. The power distribution system of the main circuit is equipped with short-circuit, over-current and voltage-loss protection. When the power supply is interrupted, the main circuit is automatically disconnected. Circuit, each mechanism is equipped with zero position protection. After the fault is restored, if the operating handle does not return to the zero position, each mechanism cannot start by itself.
Operation: All mechanisms used are operated on the ground, and the lifting, large and small vehicles are controlled by the ground buttons and the remote control.
Protection and instruction: each mechanism is equipped with limit protection, the lifting mechanism is equipped with ascending and descending limit protection, and the large and small cars are equipped with end limit protection, so the limit switches are all explosion-proof limit switches.