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Entry type: FAQ, Entry ID: 6516034, Entry date: 06/17/2010

Why do I get the signal "QBAD" on my "CH_AI" driver block?

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When I set "TC-IL" (thermo-element, internal linearization) as measuring type for the relevant analog input module, a "QBAD" signal is display on the driver block "CH_AI".
This measuring type is supported only with Hotfix 2 for PCS 7 V5.0 + SP2. You can order this hotfix free of charge in Entry ID 5934475.

Install the hotfix and copy the function FC275 manually into your program from the block library. This replaces the older driver (update date 16.11.1999) with the new driver (update date 16.10.2000). The measuring type "TC-IL" then functions with this new driver.

Since you have to copy the driver manually into the project, the drive update is only valid for the current project. You have to repeat the copying of function FC275 for new or other projects.

I/O access, Channel driver

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