Pressure limit switch circuit is cutoff, 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。
2
The simulation result shows that the dynamic response and the detection precision in detection circuit can be greatly influenced by the cut-off frequency, order and type of low pass filter.
结果表明，低通滤波器的截止频率、阶数和类型对检测电路的动态响应过程、检测精度都有很大影响。
3
Protection devices of maximum current steady and cut-off electric circuit avoid further damage of failure phone circuit board.