What are the reasons for the burning failure of explosion-proof electric hoist due to lack of phase?

Some users reported that there was a lack of phase in the process of using the explosion-proof electric hoist, the control box wire was broken and loose, and then the contactor was burned. After repairing it, it burned again less than a week, and there was a problem over and over again. What is this? Condition?

There is a problem with the wires inside the control box: After on-site investigation, the explosion-proof electric hoist will be affected in many ways during use. The tremor caused by the collision between the hopper and the acetylene generator maintenance ring during feeding; the tremor when the walking and lifting motors start and stop; the tremor caused by the acetylene generator vibrator is transmitted to the electric hoist through the hopper and the steel cable; the internal contactor of the control box The shaking that occurs when it is sucked in and released. As a result, the looseness of various lines is the external cause of the shortcomings of loose and broken wires in the control box, and the shortcomings of the fasteners in the planning, processing and installation are the root causes.

Shaking of the contactor and the central relay: Considering the impact of calcium carbide dust on the human body, there are two methods for calcium carbide feeding: on-site and remote remote control. Long-distance remote control operation is that the operator uses the cross switch on the console through the TV monitor in the central control room.

Solution: To reduce the voltage drop on the line, the direct way is to shorten the length of the control cable.