we are getting spurious readings with the turbine shut down when opening the panel door.

LVDT 96GC-2 jumps to @19%

Immediate reaction was a poor ribbon cable between <T> processor and Analog I/O module, but on replacing this the problem remains.
replaced the HSAA card in <T> and still no change.

Genuine voltage change appears on the LVDT feedback, excitation volts remains stable and removing the ribbon cable end JE-T and replacing always resets the problem and it dosent return.

All connections to the Analog IP card are OK and it only transfers through this board to the rbbon cable (no components) so don't suspect that.

Earthing of door panel is OK

If it was power supply problems, surely it would affect other readings, nothing else is affected.

Any ideas, before I start laborious substitution of components.

 

Hi,

what about a new LVDT calibration?

A.

 

For future reference the fault has been found and was on the Analog input/output module board (AIO.1)

Replacing this cured the problem

 

Thanks for the feedback!