What reasons affect the lifting of mobile scissor lift platform

The motor has a sound, but the mobile scissor lift platform does not rise how to do? There are generally the following reasons, can be ruled out one by one

1, the mobile scissor lift platform voltage is too low: check the motor load work when the starter point position, voltage fluctuation range of no more than plus or minus 10%.
2, motor reversal: arbitrarily change the position of two phases in the three-phase line.
3, the motor is out of phase: the motor does not move, and there is a humming sound; check the circuit breaker and motor wiring.
4, whether the drop valve is open: in the drop button release state, use a voltmeter to check whether the drop valve has power. If there is no electricity, check the wiring and troubleshooting; if there is electricity, then exclude the down valve itself, or replace the down valve. The slide valve of the descending valve must be kept clean and move flexibly.
5, relief valve pressure is too low: readjust the relief valve. Adjust at 100% rated load.
6、Oil level is too low, oil pump empty suction: check the oil tank scale, if the oil level is too low, please fill the hydraulic oil and then try to press the up button.
7、Clogged oil suction filter: clean the filter.
8、Oil pipe leakage: check whether there is oil leakage from the oil pipe sending joints, whether there is joint slack, tighten the oil pipe joints if there are; if the oil pipe joints are aging, they must be replaced with new ones in time.
9、It is possible that the goods contained exceed the rated load requirements.