从OPC Server读过来的tag，放在画面上的IO域中，不刷新，切换画面后，归零，什么原因？如何解决？

---

附件：

]]>https://bbs.novotific.com/topic/29/wincc画面上opc-tag为什么不刷新RSS for NodeThu, 12 Nov 2026 21:27:47 GMTThu, 03 Sep 2020 16:38:13 GMT60总结：

• OPC tag放画面上不会持续更新，只会在变化时更新。
  
• OPC tag被其他程序应用时候，才会被调用更新，比如，taglogging, alarm logging,global scripts....等
  
• OPC tag在server端被更新，也会被pool到客户端，例如tag的值一直在不断变化。
  

解决方法：

• 把要更新的opc tag放到WinCC gloabl scripts中，调用get函数不断触发刷新。
  
• 建议OPC驱动刷新，采用设备刷新，入下图。
  

---

附件：

]]>https://bbs.novotific.com/post/107https://bbs.novotific.com/post/107Thu, 03 Sep 2020 16:48:01 GMTWe talked on OPC server station right now.....

In OPC client station same rules applied

a) when OPC client tag is defined as alarm means you require OPC server must update that tag always as fast as systen can

b) when OPC client tag is defined as taglogging means you require OPC server must update that tag always with lient tag logging interval time defined in it

c) when OPC client tag is defined in a graphic page only means you require OPC server must update that tag with refresh time defined in graphic page



In the other system you can define a different time becausetooptimize network trafic and comunication, Siemens OPC client is not to optimiza comunication but for better performanc.



https://support.industry.siemens.com/tf/ww/en/posts/wincc-opc-client/31871/?page=0&pageSize=10

]]>https://bbs.novotific.com/post/106https://bbs.novotific.com/post/106Thu, 03 Sep 2020 16:44:19 GMTOPC Scout客户端是好用的，WinccFlexible也是好用的，但是就是WinCC不好用，从WinCC 7.3以后出现了这个问题。

原帖链接：

https://support.industry.siemens.com/tf/ww/en/posts/opc-problem-updating-the-value-of-the-tag/163381/?page=0&pageSize=10

]]>https://bbs.novotific.com/post/105https://bbs.novotific.com/post/105Thu, 03 Sep 2020 16:42:17 GMT 西门子论坛中提到如下：
the Tags are only be actualized, if they will be requestet by any
process in WinCC, which process is not relevant.
Graphics Runtime, Alarmlogging, Taglogging, Scripting (Global Action).
You could read all tags for example by a Global Action.

原帖链接
https://support.industry.siemens.com/tf/ww/en/posts/opc-tag-updating-problem-update-tags-on-active-screen-only/143220/?page=0&pageSize=10
]]>https://bbs.novotific.com/post/104https://bbs.novotific.com/post/104Thu, 03 Sep 2020 16:40:30 GMT