Acquisition method and system for switching signals

The present invention discloses a data collection method and a system switching signal, comprises a voltage value of the switching signal of the inputted sequence is compared with the size of the N threshold voltage value; wherein, of N threshold voltage values ​​of N predetermined threshold obtained by the digital to analog converter; N preset threshold in ascending order of a first threshold value, the second threshold value to the second threshold value N, extending to both sides of a first threshold value and the threshold value N threshold interval are composed of wiring fault condition , remaining between two adjacent threshold values ​​were composed of the N-1 is the state of the switch threshold value interval, N being a natural number greater than 3; and when the voltage value of the switching signal is greater than equal to the threshold voltage value, the first level as the comparison value output; switching signal when the voltage value is less than the threshold voltage value, the second level as a comparative value output; wherein the total number of the comparison value is N; in accordance with a first level and / or the second level, the switching signal belongs is determined state threshold value interval.