上面的地址中间有不知道为什么不少空格的（选中地址是看到好多的短竖线就是了，要把空格去掉才行，可以先粘到记事本把空格去掉）
http://www4.ad.siemens.de/csinfo/livelink.exe?func=cslib.csinfo&objId=10805588&objAction=csBrowse&foldersopen0=-652-651-645-621-154-656-&nodeID0=10805588&lang=en&siteid=cs&aktprim=0

此贴子内容大概如下
题目:Tag Logging and storage behavior in WinCC V5.0 SP2 and higher

QUESTION:
Why aren't the current values stored in the database?

ANSWER:
For the sake of performance, there are always 100 values stored in a buffer. This holds for all cyclic and sequential archives. Using the API functions you can read out the current value (e.g. TLGGetArchivData).

Keywords:
Trend configuration