Emerson Micro Motion 9739 MVD

Troubleshooting
10.13CheckHARTcommunicationloop
Prerequisites
Youwillneedthefollowing:
•Acopyofyourtransmitterinstallationmanual
•AFieldCommunicator
•Optional:theHARTApplicationGuide,availableatwww.hartcomm.org
Procedure
1.Verifythattheloopwiresareconnectedasshowninthewiringdiagramsinthetransmitter
installationmanual.
IfyourHARTnetworkismorecomplexthanthewiringdiagramsinthetransmitterinstallation
manual,contacteitherMicroMotionortheHARTCommunicationFoundation.
2.DisconnecttheprimarymAoutputwiringfromthetransmitter.
3.Installa250Ωresistoracrossthetransmitter’sprimarymAoutputterminals.
4.Checkthevoltagedropacrosstheresistor(4–20mA=1–5VDC).
Ifvoltagedropislessthan1VDC,addresistancetoachieveavoltagedropofgreaterthan1VDC.
5.ConnectaFieldCommunicatordirectlyacrosstheresistorandattempttocommunicate(poll).
Ifcommunicationwiththetransmittercannotbeestablished,thetransmittermayneedservice.
ContactMicroMotion.
10.14CheckHARTAddressandLoopCurrentMode
ThedefaultHARTAddressis0.Thisaddressisappropriateunlessthetransmitterisinamultidrop
environment.IftheHARTAddressisconguredtoavalueotherthan0,somecongurationtoolswill
automaticallychangeLoopCurrentModeaswell.
IfLoopCurrentModeisDisabled,theprimarymAoutputwillnotreportprocessvariabledataorindicate
faultconditions.
192MicroMotion9739MVDTransmitters