Hi, how are you? Please your help, how can I fix this:

As you can see, the Live Data for Position Feedback Secondary Gas Control Valve #1 and Position Feedback Secondary Gas Control Valve #2 shows Infinity U, MOOG valves works with two LVDT's KAVLICO. This picture is about LVDT's tab in ToolboxST Mark ViE. Control loop is working good, in a test we wired LVDT's Secondary valve cables to Quaternary valve and information in Mark ViE is OK. MinVrms and MaxVrms were in zero (0), values in picture were set manually.
We tried to CALIBRATE Secondary valve again but it seems this procedure depends on feedback value, which is Infinity U.
Maybe does anyone here some tip to fix it!

 

WHEN DID THIS PROBLEM START?

I'm not sure, but I believe 'Infinity U' means inifinity unhealthy.

Yes; a device with LVDTs needs to have LVDT feedback when trying to move it using the Calibration function or when trying to calibrate the LVDTs. The manual Calibrate function tells the device to move to a position and it needs feedback to know if it reaches the reference position. In automatic calibration, the Calibrate function tells the device to move to the end of travel and when it senses the LVDT feedback has stopped changing for a small period of time it thinks the device has reached the end of travel and notes the LVDT feedback for the purposes of calibrating the LVDT feedback.

So, you switched the Secondary Gas Control Valve LVDTs to the Quat LVDT input channels and it worked. I would have reconnected the Quat LVDTs to the Secondary LVDT input channels to see what happened.

Have you measured the excitation and feedback voltages of the Secondary Gas Control Valve LVDTs when they're connected to the Secondary Gas Control Valve LVDT input channels? (You could also do this with the Quat LVDTs connected to the Secondary Gas Control Valve input channels.)

It would be somewhat helpful if you could tell us what the Diagnostic Alarms for this I/O pack.

And it would be VERY helpful if you could tell us when this problem started....