Why can't the 5 tons Electric Chain Hoist Pull 3 tons Goods?

I saw a friend on the Internet asking such a question a few days ago, saying that the 5-ton electric chain hoist I bought could not pull 3 tons of goods. Under normal circumstances, the electric chain hoist with a load of 5 tons can easily lift 3 tons of goods. Why does it fail to lift?

Why can't the electric chain hoist work normally?
Reason 1: The motor terminal voltage of the electric chain hoist is more than 10% lower than the rated voltage, which causes the motor's starting torque to be too small, and the electric hoist cannot lift the goods and cannot work.

Solution: The voltage of the electric hoist is low. First, when checking, use a multimeter or voltmeter to measure the voltage at the input terminal of the motor. If the voltage is too low and the motor cannot be started, wait for the system voltage to return to normal before using the electric hoist.

Reason 2: The main and control circuits of the electric chain hoist are damaged, the circuit is disconnected or the contact is poor, so that the hoist motor cannot be energized or the power supply system cannot transmit power.

Solution: In this situation, the main and control circuits need to be overhauled. During the overhaul, in order to prevent the main and control circuits from losing phase and burning the motor, or the hoist's motor is suddenly energized and running, causing harm. To disconnect the hoist motor from the power line, only supply power to the main and control loops, then click the start and stop switches, check and analyze the working conditions of the control appliances and lines, and repair or replace the defective appliances or lines. Only when it is confirmed that the main and control circuits are not faulty, can the test run again.

Reason 3: The electric chain hoist motor was burnt due to long-term continuous high-intensity work. The electric chain hoist was not used for a long time, and the brake wheel and end cover were rusted due to poor maintenance. The motor could not rotate and the hoist could not work.

Solution: The brake wheel and end cover of the electric chain hoist are rusty. At this time, you should remove the brake wheel, clean the rusted surface, and then re-test the motor to severely sweep the bore, which will also make the motor not rotate. It is found that this situation It should be discontinued and the motor must be overhauled or replaced to ensure normal operation of the hoist.

Reason 4: The internal gear of the electric chain hoist is bitten and jammed or the chain of the electric chain hoist is jammed, which makes it impossible to hoist.

Solution: After the power is off, straighten out the chain to avoid twisting the chain. If the chain has been deformed, it needs to be replaced with a new chain before lifting.

We need to check the electric hoist step by step. When the specific problem is detected, we can follow the corresponding solution.

Why can't the 5 tons Electric Chain Hoist Pull 3 tons Goods?