Simulate tag "calc failed" for quality monitoring

Hi,

I'm a quite new user in PI.  I have to send a calculated tag from PI to an OPC server.  In parallel, I want to monitore this tag quality so if anything go wrong, I can take action automatically.

I have trouble for testing the monitoring part.  I'm using the "badVal()" function in pe but i'm not able to simulate bad values (such as "calc failed") to just see if it works.  I tried to insert non existing tags in the performance equation, the value freeze that's it.

Thanks

David