Martel LC-110 User manual

LC-110/H
Reference Manual
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1. Introduction ........................................1
1.1 Customer Service ................................................1
1.2 Standard Equipment ..............................................2
1.3 Safety information ................................................2
2. Calibrator Interface and Operation .....................5
2.1 Milliamp Source .................................................6
2.2 Milliamp Simulate.................................................7
2.3 Milliamp Measure without 24V power .................................8
2.4 Milliamp Measure with 24V power ...................................9
2.5 Volts Measure ...................................................9
3. Main Menu ........................................10
4. Calibrator Setup Menu...............................11
4.1 Setting Auto Ramp Time ..........................................11
4.2 Setting Auto Step Time ...........................................12
4.3 Enabling Valve Test ..............................................12
4.4 Enabling the HART Resistor........................................13
4.5 Selecting mA Span ..............................................13
4.6 Contrast Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.7 Configuring Auto Shutdown .......................................14
4.8 HART Write Enable...............................................14
5. Advanced Features..................................15
5.1 Step and Ramp Operation.........................................15
5.2 Valve Test ......................................................16
5.3 HART 250ΩResistor .............................................16
6. HART Device Communications ........................17
6.1. HART Connection Diagrams.......................................17
6.2 Communications Setup and Selection ...............................19
6.3 Connecting to a HART Device......................................21
6.4 Disconnect.....................................................23
6.5 Function Select Menu ............................................23
6.6 Display Setup & Data.............................................23
6.7 Modify Setup ...................................................24
6.8 Trim, Set, & Zero Menu ...........................................28
6.9 Device Diagnostic ...............................................32
6.10 Data Log & Config Log ..........................................33
6.11 HART Modem Simulation.........................................38
6.12 Error Displays..................................................39
7. Maintenance .......................................45
7.1 Replacing Batteries ..............................................45
7.2 Cleaning the Unit ................................................45
7.3 Fuse Protection .................................................45
8. Specifications .....................................46
9. Warranty ..........................................46
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1
Introduction
The Martel LC-110 and LC-110H are mA (loop) calibrators designed
to be simple to use and to offer the highest accuracy of any loop
calibrator in their class. The LC-110H differs from the standard
LC-110 in that it incorporates HART communications and supports a
select subset of the HART universal and common practice
commands. This unique feature allows the LC-110H to be used as
both a loop calibrator and basic function communicator.
The calibrator supports the following functions:
 •Currentmeasurementandsourcing,includingselectable24V
supply
 •Voltagemeasurement
 •Valvetestcapability
 •SelectableHART250Ωloop resistor
 •Outputstepandramp
The calibrator has the following features:
 •Largeeasytoreaddisplayformeasurementsanddataentry
 •Digitalknobwithselectabledecadecontrolforquickandeasy
data entry
 •Interactivemenus
 •Inputandoutputjacksprotectedbyselfresettingfuses
providingprotectionto240VAC
Inthecommunicatormodetheuserisabletoreadbasicdevice
information,performdiagnostictests,andtrimthecalibrationonmost
HARTenabledtransmitters.Inthepastthiscouldonlybedonewitha
dedicated communicator.
TheLC-110HcanalsobeusedasaHARTmodem,allowingPChost
applications to perform more sophisticated diagnostics and setup.
HARTformatcommandsfromthehostarepassedtothetransmitter,
andresponsesarepassedback.
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1.2 Standard Equipment
Checktoseeifyourcalibratoriscomplete.Itshouldinclude:
 •Calibrator
 •6xAAAbatteries(installed)
 •Testleads
- The LC-110 is supplied with one set of leads with alligator
clips installed
  -TheLC-110Hissuppliedwithtwosetsoftests.Oneset
with alligator clips and the other set with mini-grabber
style ends
 •Owner’sManual
 •NISTCertificate
1.3 Safety information
Symbols Used
ThefollowingtableliststheInternationalElectricalSymbols.Someor
all of these symbols may be used on the instrument or in this
manual.
SymbolDescription   
AC (Alternating Current)
AC-DC
Battery
CEComplieswithEuropeanUnionDirectives
DC
DoubleInsulated
ElectricShock
Fuse
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PEGround
HotSurface(BurnHazard)
ReadtheUser’sManual(ImportantInformation)
Off
On
CanadianStandardsAssociation
The following definitions apply to the terms “Warning” and “Caution”.
•“Warning”identifiesconditionsandactionsthatmayposehazards
to the user.
•“Caution”identifiesconditionsandactionsthatmaydamagethe
instrument being used.
Usethecalibratoronlyasspecifiedinthismanual,otherwiseinjury
and damage to the calibrator may occur.
Warning
To avoid possible electric shock or personal injury:
•Donotapplymorethantheratedvoltage.Seespecificationsfor
supported ranges.
•Followallequipmentsafetyprocedures.
•Nevertouchtheprobetoavoltagesourcewhenthetestleadsare
plugged into the current terminals.
•Donotusethecalibratorifitisdamaged.Beforeyouusethe
calibrator,inspectthecase.Lookforcracksormissingplastic.Pay
particular attention to the insulation surrounding the connectors.
•Selecttheproperfunctionandrangeforyourmeasurement.
•Makesurethebatterycoverisclosedandlatchedbeforeyou
operate the calibrator.
•Removetestleadsfromthecalibratorbeforeyouopenthebattery
door.
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•Inspectthetestleadsfordamagedinsulationorexposedmetal.
Checktestleadscontinuity.Replacedamagedtestleadsbefore
you use the calibrator.
•Whenusingtheprobes,keepyourfingersawayfromtheprobe
contacts. Keep your fingers behind the finger guards on the
probes.
•Connectthecommontestleadbeforeyouconnectthelivetest
lead.Whenyoudisconnecttestleads,disconnectthelivetestlead
first.
•Donotusethecalibratorifitoperatesabnormally.Protectionmay
beimpaired.Whenindoubt,havethecalibratorserviced.
•Donotoperatethecalibratoraroundexplosivegas,vapor,ordust.
•Disconnecttestleadsbeforechangingtoanothermeasureor
source function.
•Whenservicingthecalibrator,useonlyspecifiedreplacementparts.
•Toavoidfalsereadings,whichcouldleadtopossibleelectricshock
orpersonalinjury,replacethebatteryassoonasthebattery
indicator appears.
•Toavoidaviolentreleaseofpressureinapressurizedsystem,shut
off the valve and slowly bleed off the pressure before you attach
the pressure module to the pressure line.
Caution
To avoid possible damage to calibrator or to equipment under test:
•Usetheproperjacks,function,andrangeforyourmeasurementor
sourcing application.
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2. Calibrator Interface and Operation
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Source 0.00%
4.000mA
Simultaneous % Display
4mA = 0.00%
20mA = 100.00%
Cursor
100% Key: Sets Output to 20mA
25% Key: Steps 4, 8, 12, 16, 20mA
0% Key: Sets Output to 4mA
Digital Knob Sets Output Value
Press to Move Cursor
Menu
Press to Enter Setup Menu
Press Again to Exit
Step / Ramp Enable
Backlight
On / Off
Mode
Figure 1
Figure1istypicalofthemaindisplayforalloperatingmodes.It
shows the present measurement or output value. The individual
operating modes are described below.
UsetheMENU/EXITkeytodisplaythemainmenudescribedin
section3toselecttheprimaryoperatingmodeofthecalibrator,to
accessthecalibratorsetupfunctions,ortoenterHARTmode.
Inoutputmode:
 •Presstheknobtomovethedecadecursor.
 •Rotatetheknobtoincrementordecrementtheoutputinsteps
indicated by the selected decade.
 •Usethe3percentkeystodirectlysettheoutputtopreset
values.
 •Usethestep/rampkeytoselectandstoptheseadvanced
modeswhicharedescribedinsection5.1.
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2.1 Milliamp Source
InthemASourcemodethecalibratoroutputsasignalfrom0to
24mAintoaloadofupto1000ohms(750ohmsiftheinternalHART
resistor is switched on).
Figure2showsthemaindisplayandtypicalconnectionsforthis
mode.
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Source 0.00%
4.000mA
4-20mA INPUT DEVICE
RECORDER/INDICATOR
SCADA SYSTEM ETC.
(+)
(–)
4 to 20mA
Figure 2
•Presstheknobtomovethedecadecursor.
•Rotatetheknobtoincrementordecrementtheoutputinsteps
indicated by the selected decade.
•Usethe3percentkeystodirectlysettheoutputtopresetvalues.
•Usethestep/rampkeytoselectandstoptheseadvancedmodes
whicharedescribedinsection5.1.Whenautomaticsteporramp
is active one of the following is shown in the lower left corner:
Automatic step:
Automatic ramp: ∧
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•PressMENU/EXITtoenterthemainmenudescribedinsection3.
•Thetext‘ValveTest’isshowninthelowercenterwhenthevalve
testfunctionhasbeenenabledontheSetupMenu,section4.3.
Valvetestisdescribedinmoredetailinsection5.2.
•Thetext‘250Ω’textisshowninthelowerrightcornerwhenthe
HARTresistorhasbeenenabledontheSetupMenu,section4.4.
2.2 Milliamp Simulate
InthemASimulatemodethecalibratorfunctionslikea2-wire
transmitterbycontrollingtheloopcurrentfromanexternalpower
supply. This function is a great way to test a loop with the transmitter
removed.
Figure3showsthemaindisplayandtypicalconnectionsforthis
mode.
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Simulate 0.00%
4.000mA
POWER SUPPLY
30 VDC MAX
(+)
(–)
4 to 20mA
4-20mA
INPUT DEVICE
(+)
(–)
Figure 3
•Presstheknobtomovethedecadecursor.
•Rotatetheknobtoincrementordecrementtheoutputinsteps
indicated by the selected decade.
•Usethe3percentkeystodirectlysettheoutputtopresetvalues.
•Usethestep/rampkeytoselectandstoptheseadvancedmodes
whicharedescribedinsection5.1.Whenautomaticsteporramp
is active one of the following is shown in the lower left corner:
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Automatic step:
Automatic ramp: ∧
•PressMENU/EXITtoenterthemainmenudescribedinsection3.
•Thetext‘ValveTest’isshowninthelowercenterwhenthevalve
testfunctionhasbeenenabledontheSetupMenu,section4.3.
Valvetestisdescribedinmoredetailinsection5.2.
•Thetext‘250Ω’textisshowninthelowerrightcornerwhenthe
HARTresistorhasbeenenabledontheSetupMenu,section4.4.
2.3 Milliamp Measure without 24V power
InthemAMeasuremode,thecalibratordisplaystheloopcurrent.
Figure4showsthemaindisplayandtypicalconnectionsforthis
mode.
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Measure 0.00%
4.000mA
4-20mA
OUTPUT DEVICE
(+)
(–)
4 to 20mA
Figure 4
•PressMENU/EXITtoenterthemainmenudescribedinsection3.
•Thetext‘250Ω’textisshowninthelowerrightcornerwhenthe
HARTresistorhasbeenenabledontheSetupMenu,section4.4.
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2.4 Milliamp Measure with 24V power
InthemAMeasurewith24Vmode,thecalibratoroutputs24VDC
while displaying the loop current. The mode is useful for powering a
transmitter without the need for a separate power supply.
Figure5showsthemaindisplayandtypicalconnectionsforthis
mode.
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Measure 24V 0.00%
4.000mA
Figure 5
•PressMENU/EXITtoenterthemainmenudescribedinsection3.
•Thetext‘250Ω’textisshowninthelowerrightcornerwhenthe
HARTresistorhasbeenenabledontheSetupMenu,section4.4.
2.5 Volts Measure
IntheVoltsMeasuremode,thecalibratordisplaystheloopvoltage.
Figure6showsthemaindisplayandtypicalconnectionsforthis
mode.
•PressMENU/EXITtoenterthemainmenudescribedinsection3.
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MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Measure
10.000V
VOLTAGE
OUTPUT DEVICE
(+)
(–)
Figure 6
3. Main Menu
The Main Menu is used to select the primary operating mode of the
calibrator,toaccessthecalibratorsetupfunctions,andtoenterHART
mode.
mASource
mASimulate
mA Measure
mAMeasurewith24V
VoltsMeasure
CalibratorSetupMenu
HART Comm. Menu
Rotatetheknobtoselectanactionbymovingthereversevideo
highlightupanddown.Presstheknobtoperformtheselected
action.PressMENU/EXITtoreturntothemaindisplaywithout
performing an action.
The first five actions change the operating mode accordingly and
returntothemaindisplaydescribedinsection2.
The“CalibratorSetupMenu”actionisdescribedinsection4.
The “HART Comm. Menu” action is described in section 6. The
‘HART’menuitemonlyappearsontheLC-110Hdevice.
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4. Calibrator Setup Menu
The calibrator setup menu consists of two screens. The second
screenisreachedbyselecting‘OtherParameters’onthefirstscreen.
Auto Ramp Time
AutoStepTime
ValveTest
HART250ΩResistor
OtherParameters
mASpan
Contrast
AutoShutdownTime
HARTWriteEnable
Rotatetheknobtoselectanactionbymovingthereversevideo
highlightupanddown.Presstheknobtoperformtheselected
action.PressMENU/EXITtoreturntothemaindisplaywithout
performing an action.
Note:The‘HARTWriteEnable’menuitemonlyappearsonthe
LC-110H device.
4.1 Setting Auto Ramp Time
Auto Ramp Time
10SEC.
Press&holdtoSave
This function sets the full scale ramp time for the mA ramp feature
describedinmoredetailinsection5.1.Thevaluecanbesetfrom5
to 300 seconds.
Rotatetheknobtoadjustthevalue.Pressandholdtheknobtosave
it.PressMENU/EXITtorestorethepreviousvalueandreturntothe
main display.
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4.2 Setting Auto Step Time
Auto Step Time
10SEC.
Press&holdtoSave
ThisfunctionsetsthestepintervaltimeforthemAAutoStepfeature
describedinmoredetailinsection5.1.Thevaluecanbesetfrom5
to 300 seconds.
Rotatetheknobtoadjustthevalue.Pressandholdtheknobtosave
it.PressMENU/EXITtorestorethepreviousvalueandreturntothe
main display.
4.3 Enabling Valve Test
Valve Test Enable
 OFFON
This function enables and disables the valve test feature described in
moredetailinsection5.2.
Rotatetheknobtomovethereversevideohighlighttothedesired
selection.Presstheknobtosavethehighlightedselection.Press
MENU/EXITtorestorethepreviousselectionandreturntothemain
display.
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4.4 Enabling the HART Resistor
HART Resistor Enable
 OFFON
This function enables and disables the HART resistor described in
moredetailinsection5.3.
Rotatetheknobtomovethereversevideohighlighttothedesired
selection.Presstheknobtosavethehighlightedselection.Press
MENU/EXITtorestorethepreviousselectionandreturntothemain
display.
4.5 Selecting mA Span
mASpanSelection
4to20mA
0to20mA
This function selects the mA span used to calculate the percent of
spanfieldonthemaindisplay,andtosetthevalueusedbythe0%
key.
Rotatetheknobtomovethereversevideohighlighttothedesired
selection.Presstheknobtosavethehighlightedselection.Press
MENU/EXITtorestorethepreviousselectionandreturntothemain
display.
4.6 Contrast Adjustment
Contrast
Samplenormalvideo
Samplereversevideo
This function sets the display contrast.
Rotatetheknobtoadjustthecontrast.Therangeofvaluesisshown
bythebargraph,withhighercontrastshownbyalongerbar.The
samplenormalandreversevideotextlinesallowevaluationofboth
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textmodes.Presstheknobtosavethecontrastvalue.PressMENU/
EXITtorestorethepreviousselectionandreturntothemaindisplay.
4.7 Configuring Auto Shutdown
Auto Shutdown Time
10MIN.
This function sets or disables the time before the unit automatically
shutsdownifthekeypadisnotused.Thevaluecanbesetto
‘Disabled’,orfrom1to30minutes.
Rotatetheknobtoadjustthevalue.Pressandholdtheknobtosave
it.PressMENU/EXITtorestorethepreviousvalueandreturntothe
main display.
4.8 HART Write Enable
ThissettingisavailableonlyontheLC-110H.Itprotectsallfunctions
ontheModifySetupmenu,andtheDeviceDiagnostic,Trim4mA,
Trim20mA,SetFixedOutput,andPVZerofunctions.Thedefault
settingis“ON”,butmaybeturnedoffiftheuserwantstoprotect
againstunauthorizeduse.
HART Write Enable
 OFFON
Rotatetheknobtomovethereversevideohighlighttothedesired
selection.Presstheknobtosavethehighlightedselection.Press
MENU/EXITtorestorethepreviousselectionandreturntothemain
display.
Beforethesettingischanged,apasswordisrequiredtoacceptit.
Thepasswordissetto617atthefactory.Enterthepasswordonthe
following display. The range of values that can be set is 000 to 999.
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Password
000
Press&holdtoSave
Presstheknobtomovethedecadecursor.Rotatetheknobtoadjust
thevalueinstepsindicatedbythedecadeselected.Pressandhold
theknobtosavethewriteenablesetting.PressMENU/EXITto
restore the previous HART enable selection and return to the main
display.
The write enable setting is saved only when the correct password is
entered.Otherwiseanerrormessageisdisplayed.
5. Advanced Features
The calibrator has several advanced features that are available
throughtheCalibratorSetupMenus.Howthefeaturesareenabled
and what they do is described below.
5.1 Step and Ramp Operation
The calibrator has several unique features that are helpful aids when
doing milliamp calibrations.
Thepercentkeysallowtheusertosetthemilliampoutputto0%of
span,100%ofspan,orstepitby25%ofspan.
The“Step/Ramp”keyallowshandsfreeoperationbyautomatically
steppingorrampingthemilliampoutputfrom0%to100%andback
continuously.
The100%valueisalways20mA,butthe0%valuemaybe0mAor4
mAdependingonthemAspansettingdescribedinsection4.5.The
25%stepsizeiseither5mAor4mAaccordingly.
5.1.1 Manual Stepping
1. Usethemainmenutosetthecalibratortosourceorsimulate
current.
2. Pressthe“0%”keytosettheoutputto0%ofspan.
3. Pressthe“100%”keytosettheoutputto100%ofspan.
4. Pressthe“25%”keytosteptheoutputin25%ofspan
increments,from0%ofspanto100%ofspanandback.
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5.1.2 Automatic Stepping and Ramping
1. Usethemainmenutosetthecalibratortosourceorsimulate
current.
2. ThecalibratorhasseparateAutorampandsteptimes.Usethe
menu system to set the ramp or step time as described in
section4.1or4.2.
3. Pressthe“Step/Ramp”keyoncetocontinuallysteptheoutput
from0%ofspanto100%ofspanandbackinincrementsof25%
of span at the specified interval.
 Pressthe“Step/Ramp”oncemoretogotoautoramp.
 Pressoneofthepercentkeys,orthe“Step/Ramp”twicemore,to
turn off the auto step and ramp.
4. Pressthe“Step/Ramp”keytwicetocontinuallyramptheoutput
from0%ofspanto100%ofspanoverthespecifiedinterval,and
thenbackoverthespecifiedinterval.
 Pressoneofthepercentkeys,orthe“Step/Ramp”oncemore,to
turn off the auto step and ramp.
5.2 Valve Test
The calibrator has a valve test mode for verifying proper operation of
valves.Invalvetesttheusercansteptheoutputtothefollowing
values:3.8mA,4.0mA,4.2mA,8.0mA,12.0mA,16.0mA,19.8mA,
20.0mA,20.2mA,andback.
The valve test mA values are not affected by the mA span setting
describedinsection4.5
1. Usethemainmenutosetthecalibratortosourceorsimulate
current.
2. Ifvalvetestisnotenabled,usethemenusystemtoenableitas
describedinsection4.3.
3. Pressthe“Step/Ramp”keyorthe“25%”keytosteptheoutput
to verify the proper valve operation.
4. Usethemenusystemtodisablevalvetestwhendone.
5.3 HART 250ΩResistor
Thecalibratorhastheabilitytoinserta250Ωresistor in series with
the power supply in order to facilitate the use of a HART
communicator. The HART resistor is enabled through the menu
systemasdescribedinsection4.4.
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6. HART Device Communications
The HART functions are only available in the LC-110H.
Auto shutdown is disabled on entry to the HART Menus and is
restoredtoitspreviousstateuponexitfromtheHARTmenus.
Loopcurrenttrimissupportedfortransmitterdevices,butisnot
supported for actuator devices.
AllfunctionsontheModifySetupmenu,andthedevicediagnostic,
trim4mA,trim20mA,fixedoutput,andPVzerofunctionsmaybe
disabledusingthe‘HARTWriteEnable’selectionontheCalibrator
SetupMenu,describedinsection4.8.Ifanyofthesefunctionsare
required,theymustbeenabledbeforeenteringtheHARTmenus.
6.1. HART Connection Diagrams
6.1.1 In Circuit, External Loop Power
In“mAMeasure”modetheLC-110Hisincircuitandlooppoweris
suppliedexternallyasshownbelow.
24V
SUPPLY
(+)
(–)
4 to 20mA
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Measure 0.00%
4.000mA
250Ω
Note:Inthissituationthe250ΩHARTresistorisenabled.Ifyourloop
alreadyhas250Ω,donotenabletheHARTresistor.
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6.1.2 In Circuit, LC-110H Loop Power
In“mAMeasurewith24V”modetheLC-110Hisincircuitandthe
loop power is supplied by the LC-110H as shown below.
(+) (–)
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
Measure 24V 0.00%
4.000mA
250Ω
Note:Inthissituationthe250ΩHARTresistorisenabled.Ifyourloop
alreadyhas250Ω,donotenabletheHARTresistor.
6.1.3 Across Circuit, Communicator Only
In“CommunicatorOnly”modetheLC-110Hisacrossthecircuitand
thelooppowerissuppliedexternallyasshownbelow.
MARTEL ELECTRONICS
LC-110H Precision Loop
Calibrator w/HART™
100%
25%
0%
MENU
EXIT
PT12234
Device Setup & Data
Write LRV & URV Value
Trim, Set, & Zero
Device Diagnostic
Data Log & Config Log
24V
SUPPLY
(+)
(–)
4 to 20mA RL≥250Ω
Note:IntheCommunicatorOnlyMode,theremustbe250Ωs
resistance present in the loop.
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