Overvoltage amplitude is higher than initialization value , data acqusition card start sampling . when sampling is over , computer save data to file . engineer can analyse parameter of waveform by appropriative software reading data from file . in the trial measurement , the device shows good performance . simulant trial and actual result indicate that method in the paper acquire approving effect , and the device can be used in the lokv distribution network 当装置在线运行时，系统中出现的过电压信号通过分压器传递到同轴电缆，通过触发电路判断，如果大于预先设定的值则启动采集卡的同时采样，采样结束后，计算机把数据存盘并以文件格式保存，管理人员随时通过调用专用软件调取文件进行各种参数分析。
Based on the analysis of the effect on the maximum range of the equation ' s each parameter and the traditional method of extinction ratio , the noncooperative regulable attenuation - measure the minimum detectable power of laser altimeter on the condition of constant miss probability by attenuating the laser power transmitting to the diffuse reflected simulant target - was put forward 在传统的消光系数法基础上，根据对月测距方程各系数的影响权重分析，提出了非合作目标可调衰减法，即：通过对漫反射模拟目标，衰减出射激光功率，在一定的漏警概率条件下测量激光高度计的最小可探测功率。
