Few of our EH Control Valve (Servo Operated) having problem with Feedback. Servo modules are fine. Cables/Grounding checked and no issue although sometimes One of the redundant coil feedback goes bad randomly. Have anyone had similar problem? Moog Supplied Servo are very accurate & reliable in general and hardly you see problem with LVDT that is why not ready to believe. These are very new valves, less than 1 year, just commissioned. Total 6 Valves have similar problem.

 

Control,

Can you describe your problem in detail and some information about your plant and operating systems etc.. ?

- M M Ahsan

 

Mitsubishi 501G Gas Turbine
Netmation Control System
Moog EH Control Valve
Problem: Sometimes continuously Feed back signal fluctuate. Modules, System, Wiring, Grounding All (wires) okay but no issue found

 

Control,

My experience for EH control valve supplied by MHI, one problem was high vibration at EH pipe (steam turbine) but no effect to valve control loop.