what is output bias in control valve positioner ? what is output bias in control valve positioner ? ENG__AHMED (Electrical) (OP) 21 Mar 17 10:09 after installing a new control valve positioner (fisher DVC6200) & while making auto travelling it stopped at stage "adjusting output bias" and didn't continue auto travelling . -what is meant by "output bias" & why it stopped ?? RE: what is output bias in control valve positioner ? danw2 (Industrial) 21 Mar 17 14:47 The term 'output bias' is mentioned as part of the auto-travel calibration routine, but the term is not defined. If output refers to the positioner's pneumatic output, it could be a pressure offset needed to move off the zero % point (?). The auto-travel section of the manual (below) lists some other errors that might warrant looking at for things to check, because I'm guessing that the auto-travel calibration did not complete because of this output bias error? is anything moving at all during the test? Linkage alignment issue? inadequate air supply? RE: what is output bias in control valve positioner ? IRstuff (Aerospace) 21 Mar 17 15:00 Is there some reason you can't talk to the supplier of the control valve positioner? TTFN (ta ta for now) I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm RE: what is output bias in control valve positioner ? Skogsgurra (Electrical) 21 Mar 17 18:30 One good reason may be that EngTips is available for this kind of questions 24/7. And that you usually get answers a lot faster than the supplier's help desk (if it exists at all). Gunnar Englund www.gke.org -------------------------------------- Half full - Half empty? I don't mind. It's what in it that counts.