Emerson Exchange 365

Hi,

We have Double Acting/Spring return/Air-to-close 228.6mm stroke valve with DVC 6200F.

There are few issues with this are :

1) Valve drives to 55% : when power is given through FF power supply and TREX communicator is being connected to DVC (by Communicator or ValveLink App), it drives valve to 50%, note that no calibration or stroke mode is yet selected, not even FF connection established, this happens just when DVC detects FF signal.

Note : this happens when the DVC FF Block is in AUTO mode, when it is changed to OOS mode, it goes to previous position when OOS mode was exited.

2) the valve have position error of (+) 4~5% at 25, 50 and 75 positions, 0 and 100% positions seem mechanically limited so errors are not possible to identify at those levels. we have tried AUTO CAL 2-3 times but the result is same.

Note : Characterization table option to remove the error is not acceptable to QC.

Pls advice, thanks.