Measures to deal with the failure of the limit device of the wire rope electric hoist

The limit device on the wire rope electric hoist is located below the drum. When a heavy object is lifted and touches the limit device, the electric hoist will automatically cut off power, and the heavy object will rise to prevent damage to the drum. At the same time, it also provides protection for the electric hoist. If the limit device fails, it will not be able to protect the electric hoist, and the consequences will be very serious. So how to prevent the limit device of the wire rope electric hoist from failing?

1. It is strictly prohibited to pull or hang the rope diagonally, as it can cause lateral force on the rope guide, resulting in its breakage and damage.

2. The upper and lower limits of the flame arrester are adjusted appropriately and tightened in place to prevent loosening and changes in the high and low limit positions.

3. The correct wiring of the flame arrester is 5 wires, with phase B being the common wire. The terminal near the push rod is connected to the AC phase of the rising contactor, and the other side is connected to the AC phase wire of the falling contactor. If this position is reversed, when the rising limit push rod contacts the flame arrester, the electric hoist can still rise but not downwards. Conversely, when the falling limit push rod contacts the flame arrester, the electric hoist can still descend but not upwards.

4. Regularly inspect the safety components of lifting equipment, promptly handle any abnormalities, and eliminate potential faults in their early stages.

5. The control ring of the wire rope electric hoist has been improved by adding a main power contactor. Previously, there was no main power contactor in the control box of the electric hoist, and the emergency stop switch on the control handle only cut off the control power, without protecting against the problem of the contactor getting stuck or stuck. After adding the main power contactor, the emergency stop switch on the control handle can be used to control its on/off, which can effectively prevent accidents caused by the inability to disconnect the lifting contactor.

6. The rated current selection of the flame arrester must be greater than the working current of the electric hoist, at least 1.5 times the working current.