Pressure limit switch circuit is cut off, stop, and then closing, the hook can only decrease.

压下限位开关，切断电路停车，再合闸时，吊钩只能下降。

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When the arm runs to the upper and lower two limit position, respectively press the lower limit switch, cut off the main control circuit, variable amplitude motor parking, to limit the role.

当臂杆运行到上下两个极限位置时，分别压下限位开关，切断主控电路，变幅电机停车，达到限位的作用。

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Instruments based on the lower limit of two switch-contact device, the pressure to set a signal or when the value of on-off control circuit for the operating system's automatic control or the use.

仪表设上、下限二位开关型接点装置，在压力达到设定值时发出信号或通断控制电路，供作业系统自动控制或发讯用。

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