看看这个：
https://support.automation.siemens.com/CN/llisapi.dll/24106357?func=ll&objId=34281179&objAction=csView&ehbid=24106357&query=%E5%A6%82%E4%BD%95%E5%90%8C%E6%AD%A5%E6%93%8D%E4%BD%9C%E9%9D%A2%E6%9D%BF%E4%B8%8ES7%2D200%2F300%2F400+%E6%8E%A7%E5%88%B6%E5%99%A8%E9%97%B4%E7%9A%84%E6%97%A5%E6%9C%9F%E5%92%8C%E6%97%B6%E9%97%B4&lang=zh&siteid=cseus&aktprim=0&extranet=standard&viewreg=CN&load=treecontent