请教关于NPD检测器信号重现性不好的问题！

你用的是哪一家的仪器啊,仪器的重现性好不好啊,repeat ability if have no problem, the NPD detector is no problem. But day by day the mobile phase will be change, it can also influence the data that you mean. so please fix the problem first. I encourage you to learn more about their manual if you want to slove this problem by yourself. or you can ask the service engenieer.