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CDT-MOD-2000 CARBON DIOXIDE TRANSMITTERS

HK Instruments CDT-MOD-2000 CARBON DIOXIDE TRANSMITTERS Operating instructions

  • Hello! I'm a chat assistant, and I've reviewed the installation instructions for the HK Instruments CDT-MOD-2000 series carbon dioxide transmitters. This document covers essential information about mounting, wiring, and configuring the device, which includes details on their CO2, temperature, and optional humidity measurement capabilities, as well as Modbus communication and self-calibration. I am ready to help you with any questions you have about these devices.
  • What are the measurement ranges for this device?
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Copyright HK Instruments 2022 www.hkinstruments. Installaon version 8.0 2022
INSTALLATION
INSTRUCTIONS
CARBON DIOXIDE TRANSMITTERS
CDT-MOD-2000 Series
• READ THESE INSTRUCTIONS CAREFULLY BEFORE
ATTEMPTING TO INSTALL, OPERATE OR SERVICE THIS
DEVICE.
• Failuretoobservesafetyinformaonandcomplywith
instruconscanresultinPERSONALINJURY,DEATHAND/OR
PROPERTY DAMAGE.
• Toavoidelectricalshockordamagetoequipment,disconnect
powerbeforeinstallingorservicinganduseonlywiringwith
insulaonratedforfulldeviceoperangvoltage.
• Toavoidpotenalreand/orexplosiondonotuseinpotenally
ammableorexplosiveatmospheres.
• Retaintheseinstruconsforfuturereference.
• Thisproduct,wheninstalled,willbepartofanengineered
systemwhosespecicaonsandperformancecharacteriscs
arenotdesignedorcontrolledbyHKInstruments.Review
applicaonsandnaonalandlocalcodestoassurethatthe
installaonwillbefunconalandsafe.Useonlyexperiencedand
knowledgeabletechnicianstoinstallthisdevice.
Thank you for choosing an HK Instruments CDT-MOD-2000 series
carbon dioxide transmier. The CDT-MOD-2000 series is intended
for use in commercial environments in HVAC/R applicaons. The
CDT-MOD-2000 series measures carbon dioxide (CO2), ulizing the
industrystandardNDIRmeasurementprinciple,andtemperature(T).
Oponal relave humidity (rH) measurement is also available in the
same device. The CDT-MOD-2000 series devices are available with
largetouchscreendisplaymakingtheconguraonofthedevicequick
andeasy.ConguraonisalsopossibleviaModbusnetwork.
The CDT-MOD-2000 series transmiers calibrate themselves auto-
macallyusingABCTMlogic.TheABCTMlogicrequiresthatthespacein
whichthetransmierisusedneedstotobeunoccupiedforfourhours
per day so that the indoor CO2 concentraon drops to the outside
level.CDT-MOD-2000-DCisadualchannelmodelwithameasuring
channelandareferencechannelthatmakesaconnuouscomparison
and the necessary adjustment accordingly. CDT-MOD-2000-DC is
alsosuitableforbuildingsthatareconnuouslyoccupied.
•humidityinvariousindustrialapplicaons
•temperaturesinHVAC/Renvironment
•CDT-MOD-2000-DCseriesdevicescanalsobeusedinapplicaons
wherethereisaconstantsourceofcarbondioxidepresent(for
examplehospitalsandgreenhouses)
SPECIFICATIONS
Performance
Measurement ranges:
CO2:400–2000ppm
Temperature:0...50°C
Relavehumidity:0–100%
Accuracy:
CO2:±40ppm+3%ofreading,DCmodel:75ppmor10%
ofreading(whicheverisgreater)
Temperature:<0.5ºC
Relavehumidity:±2...3%at0...50°Cand10–90%rH
Totalerrorbandincludesaccuracy,hysteresisand
temperatureeectover5...50°Cand10–90%rH.
Technical Specicaons
Media compability:
Dryairornon-aggressivegases
Measuring units:
ppm,°Cand%rH
Measuring element:
CO2:Non-dispersiveinfrared(NDIR)
Temperature: Pt1000(modelswithoutrH-measurement)
 Integrated(modelswithrH-measurement)
Relavehumidity:Thermosetpolymercapacivesensing
element
Calibraon:
Automacself-calibraonABCLogicTMorconnuous
comparison(DC)
Environment:
Operangtemperature:0...50°C
Storagetemperature:-20...70°C
Humidity:0to95%rH,noncondensing
Physical
Dimensions:
Case:99x90x32mm
Weight:
150g
Mounng:
3screwholessloed,3.8mm
Materials:
Case: ABS
Protecon standard:
IP20
Display (Oponal)
Touchscreen
Size:77.4x52.4mm
Electrical connecons:
Powersupply:
 5-screwterminalblock
 (24V,GND)
 0.2–1.5mm2(16–24AWG)
Relay out:
 3-screwterminalblock
 (NC,COM,NO)
 0.2–1.5mm2(16–24AWG)
Electrical
Input: 24VACorVDC,±10%
 Currentconsumpon:max90mA(at24V)+
 10mAforeachvoltageoutputor20mAfor
 eachcurrentoutput
Relay out:
 SPDTRelay,250VAC/30VDC/6A
 Adjustableswitchingpointandhysteresis
Oneanalogoutputforselectedmedia:
0/2*–10VDC,LoadRminimum1kΩ
*(2–10VDCdisplaymodelsonly) or
4–20mA,maximumload500Ω
Communicaon
Protocol:MODBUSoverSerialLine
TransmissionMode:RTU
Interface:RS485
Byteformat(11bits)inRTUmode:
 CodingSystem:8-bitbinary
 BitsperByte:
 1startbit
 8databits,leastsignicantbitsent
 rst
 1bitforparity
 1stopbit
Baudrate:selectableinconguraon
Modbusaddress:1−247addressesselectablein
conguraonmenu
Conformance
Meetsrequirementsfor:
CE:  UKCA:
EMC:  2014/30/EU S.I.2016/1091
RoHS:  2011/65/EU S.I.2012/3032
LVD/EESR: 2014/35/EU S.I.2016/1101
WEEE:  2012/19/EU S.I.2013/3113
INTRODUCTION
APPLICATIONS
WARNING
CDT-MOD-2000seriesdevicesarecommonlyusedtomonitor:
• CO2andhumiditylevelsinoces,publicspaces,meengrooms
andclassrooms
• CO2levelsofreturnairinvenlaonsystems
•incomingairandreturnairhumiditylevelsinvenlaonsystem
RoHS
COMPLIANT
Copyright HK Instruments 2022 www.hkinstruments. Installaon version 8.0 2022
SCHEMATICS
DIMENSIONAL DRAWINGS
INSTALLATION
STEP 1: MOUNTING THE DEVICE
1)Mountthedeviceinthedesiredlocaon(seestep1).
2)Routethecablesandconnectthewires(seestep2).
3)Thedeviceisnowreadyforconguraon.
WARNING!Applypoweronlyaerthedeviceisproperlywired.
Figure 1a - Surface mounng
1)Selectamounnglocaononthewallat1.2–1.8m(4–6)above
theoorandatleast50cm(20in)fromtheadjacentwall.Do
notblockdeviceairventsfromanydireconandleaveatleast
20cm(8in)gaptootherdevices.Locatetheunitinanareawith
goodvenlaonandanaveragetemperature,whereitwillbe
responsivetochangestotheroomcondions.TheCDT-MOD
shouldbemountedonaatsurface.
DonotlocatetheCDT-MODwhereitcanbeaectedby:
•Directsunlight
•Drasordeadareasbehinddoors
•Radiantheatfromappliances
•Concealedpipesorchimneys
•Outsidewallsorunheated/uncooledareas
2)Usethedeviceasatemplateandmarkthescrewholes.
3)Mountthewallplatewithscrews.
•Incorrectinstallaonmaycauseashiintemperatureoutput
•Securethelidwithalockingscrew,iftherelayisconnectedtothe
mainspower
Display locking
jumper
Output mode
selecon
jumpers
Contact pins for
relay terminal
Contact pins for
terminal block
Terminal block
Terminal block for relay
99.0
90.0
83.0
49.5
14.0
45.0
18.0
Ø 4.0
32.0
YES NO NO
Figure 1b - Mounng orientaon
Copyright HK Instruments 2022 www.hkinstruments. Installaon version 8.0 2022
CAUTION!
•ForCEcompliance,aproperlygroundedshieldingcableis
required.
•Usecopperwireonly.Insulateorwirenutallunusedleads.
•Supplyaseparatecableforrelayandsignaloutwhenusingline
voltagetopowertherelay.
•Anywiringmaycarrythefulloperanglinevoltagecurrentbased
oneldinstallaon.Thecoverlockingscrewmustbeinstalledif
thelinevoltageissuppliedtotherelay.
•Careshouldbeusedtoavoidelectrostacdischargetothe
device.
•Thisunithasconguraonjumpers.Youmayneedtorecongure
thisdeviceforyourapplicaon.
1)Routethecablesthroughthesquareopeninginthebackplateor
forsurfacewiringselectaknockoutonthetoporboomofthe
wallplate,asshowninFigure2a.
2)ConnectthewiresasshowninFigure2band2c.
STEP 3: CONFIGURATION
WIRING DIAGRAMS CONTINUED
ConguraonoftheCDT-MOD-2000seriesdeviceconsistsof:
1)Conguringthejumpers(seestep4)
2)Conguraonmenuopons.(Displayversionsonly.Seethe
usermanualforfurtherdetails)
Figure 2a - Roung the cables
24 V
GND
A
B
Analog
+
Output 0/2–10 V / 4–20 mA
output
Figure 2b - Wiring diagram: Power input & signal output
Wires can be routed through the square opening in the back plate
Wires can be routed through the top knockouts
Wires can be routed through the boom knockouts
Figure 2d - Wiring diagram: Relay
NC
COM
NO
STEP 2: WIRING DIAGRAMS
NOTE!Whenusinglongconneconwiresitmaybenecessarytouseaseparate
GNDwire forvoltage output currentto preventmeasurement distoron. The
needforanextraGNDwiredependsonthecrossseconandlengthoftheused
conneconwires.Iflongand/orsmallcrossseconwiresareused,supplycur-
rentandwireresistancemaygenerateavoltagedropinthecommonGNDwire
resulnginadistortedoutputmeasurement.WhenusingACpowersupply,make
surethatthegroundpotenalofthesignalisthesameasthegroundpotenalof
thesupplyvoltagetoavoidshortcircuitthroughtheaddionalGNDwire.
Itisrecommendedtouseshieldedtwistedpaircableformodbuscabling.
Thecableshieldmustbeearthedonlyinonepoint,normally,attheendof
themaincable.
24 V
GND
A
B
+
Analog
Output 0/2...10 V
V
output
Figure 2c - Wiring diagram: Extra GND wire
STEP 4: Jumper settings
(Grey colour indicates that a jumper is installed)
No jumper
Circuit open
Jumper installed
Circuit closed
Jumper stored
Figure 3 - Jumper installaon
1)Conguraonoftheoutputmodes:
Selecttheoutputmode,current(4–20mA)orvoltage(0–10V),
byinstallingjumpersasshowninFigure4.
Toselect2–10Voutputmodeonadisplayversionofthedevice:
First,select0–10Voutputbyjumper,thenchangethevoltage(V)
outputfrom0–10Vto2–10Vviatheconguraonmenu.Please
seetheusermanualformoredetails.
Jumper installed to the le side pins:
0–10 V output selected
N/A
N/A
Analog
0...10 V 4...20 mA
Jumper installed to the right side pins:
4–20 mA output selected
N/A
N/A
Analog
0...10 V 4...20 mA
Figure 4
2)Lockingthedisplay:
Installthejumpertolockthedisplaytopreventaccesstothe
conguraonmenuaerinstallaoniscompleted(seethe
schemacsforthelocaonofthepins).
Copyright HK Instruments 2022 www.hkinstruments. Installaon version 8.0 2022
The seller is obligated to provide a warranty of ve years for the delivered
goods regarding material andmanufacturing. The warranty period is consid-
eredtostartonthedeliverydateoftheproduct.Ifadefectinrawmaterials
oraproduconawisfound,thesellerisobligated,whentheproductissent
tothesellerwithoutdelayorbeforeexpiraonofthewarranty,toamendthe
mistake athis/her discreon either byrepairing thedefecve product or by
deliveringfreeofchargetothebuyeranewawlessproductandsendingitto
thebuyer.Deliverycostsfortherepairunderwarrantywillbepaidbythebuyer
andthereturncostsbytheseller.Thewarrantydoesnotcomprisedamages
causedbyaccident,lightning,oodorothernaturalphenomenon,normalwear
andtear,improperorcarelesshandling,abnormaluse,overloading,improper
storage,incorrectcareorreconstrucon,orchangesandinstallaonworknot
donebytheseller.Theseleconofmaterialsfordevicespronetocorrosionis
thebuyer’sresponsibility,unlessotherwiseislegallyagreedupon.Shouldthe
manufactureralterthestructureofthedevice,thesellerisnotobligatedto
makecomparablechangestodevicesalreadypurchased.Appealingforwar-
rantyrequiresthatthebuyerhascorrectlyfullledhis/herduesarisenfrom
thedeliveryandstatedinthecontract.Thesellerwillgiveanewwarrantyfor
goodsthathavebeenreplacedorrepairedwithinthewarranty,howeveronly
totheexpiraonoftheoriginalproduct’swarrantyme.Thewarrantyincludes
therepairofadefecvepartordevice,orifneeded,anewpartordevice,but
notinstallaonorexchangecosts.Undernocircumstanceisthesellerliablefor
damagescompensaonforindirectdamage.
Register Parameter descripon Data Typ e Value Range
4x0001 ParameterforP-controller 16bit 0...3 0=CO2,1=rH,2=TE,3=MAX
4x0002 CO2hIghlimit 16bit 500...2000 500...2000ppm
4x0003 CO2lowlimit 16bit 0...1900 0...1900ppm
4x0004 rHhighlimit 16bit 100...1000 10.0...100.0%
4x0005 rHlowlimit 16bit 0...900 0.0...90.0%
4x0006 TEhighlimit 16bit 50...500 5.0...50.0°C
4x0007 TElowlimit 16bit 0...450 0...45.0°C
4x0008 Parameter for relay 16bit 0...3 0=CO2,1=rH,2=TE,(3=O)
4x0009 CO2relayon 16bit 500...1950 500...1950ppm
4x0010 CO2relayo 16bit 450...1900 450...1900ppm
4x0011 rH relay on 16bit 15...990 1.5...99.0%
4x0012 rHrelayo 16bit 10...985 1.0...98.5%
4x0013 TE relay on 16bit 15...490 1.5...49.0°C
4x0014 TErelayo 16bit 10...485 1.0...48.5°C
4x0015 CO2Oset 16bit -200…200 -200…200ppm
4x0016 RHOset 16bit -100…100 -10.0…10.0%rH
4x0017 TEOset 16bit -50…50 -5.0…5.0°C
Funconcode03-Readinputholdingregister
Funconcode04-Readinputregister
Register Parameter descripon Data Typ e Value Range
3x0001 ParameterforP-controller 16bit 0...3 0=CO2,1=rH,2=TE,3=MAX
3x0002 CO2reading 16bit 0...2000 0...2000ppm
3x0003 rHreading 16bit 0...1000 0,0...100.0%
3x0004 Temp.reading 16bit 0...500 0.0...50.0°C
3x0005 CO2highlimit 16bit 500...2000 500...2000ppm
3x0006 CO2lowlimit 16bit 0...1900 0...1900ppm
3x0007 rHhighlimit 16bit 100...1000 10.0...100.0%
3x0008 rHlowlimit 16bit 0...900 0.0...90.0%
3x0009 TEhighlimit 16bit 50...500 5.0...50.0°C
3x0010 TElowlimit 16bit 0...450 0...45.0°C
3x0011 Parameter for relay 16bit 0...3 0=CO2,1=rH,2=TE,(3=O)
3x0012 CO2relayon 16bit 500...1950 500...1950ppm
3x0013 CO2relayo 16bit 450...1900 450...1900ppm
3x0 014 rH relay on 16bit 15...990 1.5...99.0%
3x0015 rHrelayo 16bit 10...985 1.0...98,5%
3x0016 TE relay on 16bit 15...490 1.5...49.0°C
3x0017 TErelayo 16bit 10...485 1.0...48.5°C
3x0018 CO2Oset 16bit -200…200 -200…200ppm
3x0 019 RHOset 16bit -100…100 -10.0…10.0%rH
3x0020 TEOset 16bit -50…50 -5.0…5.0°C
3x0021 Programversion 16bit 10…9999 1.0…999.9
MODBUS REGISTERS CONTINUED
Funconcode16-Writemulpleregisters
Register Parameter descripon Data Typ e Value Range
4x0001 ParameterforP-controller 16bit 0...3 0=CO2,1=rH,2=TE,3=MAX
4x0002 CO2hIghlimit 16bit 500...2000 500...2000ppm
4x0003 CO2lowlimit 16bit 0...1900 0...1900ppm
4x0004 rHhighlimit 16bit 100...1000 10.0...100.0%
4x0005 rHlowlimit 16bit 0...900 0.0...90.0%
4x0006 TEhighlimit 16bit 50...500 5.0...50.0°C
4x0007 TElowlimit 16bit 0...450 0...45.0°C
4x0008 Parameter for relay 16bit 0...3 0=CO2,1=rH,2=TE,(3=O)
4x0009 CO2relayon 16bit 500...1950 500...1950ppm
4x0010 CO2relayo 16bit 450...1900 450...1900ppm
4x0011 rH relay on 16bit 15...990 1.5...99.0%
4x0012 rHrelayo 16bit 10...985 1.0...98.5%
4x0013 TE relay on 16bit 15...490 1.5...49.0°C
4x0014 TErelayo 16bit 10...485 1.0...48.5°C
4x0015 CO2Oset 16bit -200…200 -200…200ppm
4x0016 RHOset 16bit -100…100 -10.0…10.0%rH
4x0017 TEOset 16bit -50…50 -5.0…5.0°C
RECYCLING/DISPOSAL
The parts le over from installaon should be
recycled according to your local instrucons.
Decommissioned devices should be taken to a
recyclingsitethatspecializesinelectronicwaste.
WARRANTY POLICY
Register Parameter descripon Data Typ e Value Range
1x0001 Relay status Bit0 0...1 0=O-1=On
1x0002 Relaytrend Bit0 0...1 0=Increasing,1=Decreasing
1x0003 Timer status Bit0 0...1 0=O-1=On
Funconcode02-Readinputstatus
Funconcode06-Writesingleregister
Register Parameter descripon Data Typ e Value Range
4x0001 ParameterforP-controller 16bit 0...3 0=CO2,1=rH,2=TE,3=MAX
4x0002 CO2hIghlimit 16bit 500...2000 500...2000ppm
4x0003 CO2lowlimit 16bit 0...1900 0...1900ppm
4x0004 rHhighlimit 16bit 100...1000 10.0...100.0%
4x0005 rHlowlimit 16bit 0...900 0.0...90.0%
4x0006 TEhighlimit 16bit 50...500 5.0...50.0°C
4x0007 TElowlimit 16bit 0...450 0...45.0°C
4x0008 Parameter for relay 16bit 0...3 0=CO2,1=rH,2=TE,(3=O)
4x0009 CO2relayon 16bit 500...1950 500...1950ppm
4x0010 CO2relayo 16bit 450...1900 450...1900ppm
4x0011 rH relay on 16bit 15...990 1.5...99.0%
4x0012 rHrelayo 16bit 10...985 1.0...98.5%
4x0013 TE relay on 16bit 15...490 1.5...49.0°C
4x0014 TErelayo 16bit 10...485 1.0...48.5°C
4x0015 CO2Oset 16bit -200…200 -200…200ppm
4x0016 RHOset 16bit -100…100 -10.0…10.0%rH
4x0017 TEOset 16bit -50…50 -5.0…5.0°C
STEP 5: MODBUS REGISTERS
FunconsforModbuscommunicaon:
Funcon Code Descripon
01 Readcoilstatus
02 Readinputstatus
03 Readholdingregisters
04 Readinputregisters
05 Forcesinglecoil
06 Presetsingleregister
07 Readexceponstatus
15 Forcemulplecoils
16 Presetmulpleregisters
17 ReportslaveID
Funconcode05-Writesinglecoil
Register Parameter descripon Data Typ e Value Range
0x0001 Relaytrend Bit0 0...1 0=Increasing,1=Decreasing
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