661系列带偏压放大继电器，Siemens661继电器661系列带偏压放大继电器，Siemens661继电器简单介绍Fixed-gainforceandbiasadjustmentmechani***samplifypneumaticinstrumentsignalstoprovidecontrolcircuitdesignflexibility661系列带偏压放大继电器AmplifyingRelayswithBiasSiemens661继电器的详细介绍Features&BenefitsFixed-gainforceandbiasadjustmentmechani***samplifypneumaticinstrumentsignalstoprovidecontrolcircuitdesignflexibilityDescriptionSeries661AmplifyingRelaysarefixed-gainforce-balanceinstruments,whichincorporatebiasadjustmentthatamplifypneumaticinstrumentsignals.Forexample,a3-15psisignalcanbeamplifiedtooperatea3-27psicontrolvalve.Theinputpressuresignal,actingupontheeffectiveareaoftheupperdiaphragm,producesaforceopposedbytheforceproducedbytheoutputpressureappliedovertheeffectiveareaofthelowerdiaphragmandbyamanually-set(c***tant)springforce.Anyinbalanceintheopposingforceswilloperatethepilotvalvetothrottlesupplyairtochangetheoutputuntilrebalanceisachieved.Plusorminusbiasingoftheinputsignalisaccomplishedbychangingthesettingoftheupperbiasingspring,whichaltersthenetspringforceonthediaphragmassembly)