HK Instruments RHT-MOD Series User manual

Copyright HK Instruments 2021 www.hkinstruments. Installaon version 7.0 2021
INSTALLATION
INSTRUCTIONS
HUMIDITY TRANSMITTERS
RHT-MOD Series
• READ THESE INSTRUCTIONS CAREFULLY BEFORE
ATTEMPTING TO INSTALL, OPERATE OR SERVICE THIS
DEVICE.
• Failuretoobservesafetyinformaonandcomplywith
instrucons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.
SPECIFICATIONS
Thank you for choosing an HK Instruments RHT-MOD series rela-
vehumiditytransmier.TheRHT-MODseriesisintendedforusein
commercialenvironmentsinHVAC/Rapplicaons.
TheRHT-MODmeasuresrelavehumidity(rH),andtemperature(T).
RHT-MODdevicesareavailablewithlargetouchscreendisplaymak-
ingconguraonofthedevicequickandeasy.
RHT-MODseriesdevicesarecommonlyusedtomonitor:
•humidityandtemperaturelevelsinoces,publicspaces,hospitals,
meengroomsandclassrooms
•humidityandtemperatureinvariouscommercialapplicaons
•humidityandtemperatureinHVAC/Renvironment
SPECIFICATIONS
Performance
Measurement ranges:
Temperature:0...50°C
Relavehumidity:0–100%
Accuracy:
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:
°Cand%rH
Measuring element:
Temperature:Integrated
Relavehumidity:Thermosetpolymercapacive
sensingelement
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
Protecon standard:
IP20
Display
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(12–24AWG)
Relayout:
 3-screwterminalblock
 (NC,COM,NO)
 0.2–1.5mm2(12–24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marking:
EMCDirecve2014/30/EU
RoHSDirecve2002/95/EC
LVDDirecve2014/35/EU
WEEEDirecve2012/19/EU
INTRODUCTION WARNING
APPLICATIONS
COMPANY WITH
MANAGEMENT SYSTEM
CERTIFIED BY DNV GL
= ISO 9001 = ISO 14001 =
RoHS 2
2011/65/EU

Copyright HK Instruments 2021 www.hkinstruments. Installaon version 7.0 2021
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RHT-MOD
shouldbemountedonaatsurface.
DonotlocatetheRHT-MODwhereitcanbeaectedby:
•Directsunlight
•Dras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
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 2021 www.hkinstruments. Installaon version 7.0 2021
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
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
NC
COM
NO
STEP 2: WIRING DIAGRAMS
Figure 2d - Wiring diagram: Relay
NOTE!Whenusinglongconneconwiresitmaybenecessarytousea
separateGNDwireforvoltageoutputcurrenttopreventmeasurementdis-
toron.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currentandwireresistancemaygenerateavoltagedropin
thecommonGNDwireresulnginadistortedoutputmeasurement.
24 V
GND
A
B
+
Analog
Output 0/2...10 V
V
output
Figure 2c - Wiring diagram: Extra GND wire
ConguraonoftheRHT-MOD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)
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.

Copyright HK Instruments 2021 www.hkinstruments. Installaon version 7.0 2021
Thesellerisobligatedtoprovideawarrantyofveyearsforthedeliv-
eredgoodsregardingmaterialandmanufacturing.Thewarrantyperiod
isconsidered 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orcarelesshandling,abnormaluse,overloading,im-
properstorage,incorrectcareorreconstrucon,orchangesandinstal-
laonworknotdonebythesellerorhis/herauthorizedrepresentave.
Theseleconofmaterialsfordevicespronetocorrosionisthebuyer’s
responsibility,unlessotherwiseislegallyagreedupon.Shouldtheman-
ufactureralterthestructureofthedevice,thesellerisnotobligatedto
makecomparablechangestodevicesalreadypurchased.Appealingfor
warranty 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expiraon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 ex-
change costs. Under no circumstance is the seller liable for damages
compensaonforindirectdamage.
STEP 5: MODBUS REGISTERS
Register Parameter descripon Data Type Value Range
1x0001 Relay status Bit0 0...1 0=O-1=On
1x0002 Relaytrend Bit0 0...1 0=Increasing,1=Decreasing
Funconcode02-Readinputstatus
Register Parameter descripon Data Type Value Range
4x0001 ParameterforP-controller 16bit 0...3 1=rH,2=TE,3=MAX
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 1=rH,2=TE,(3=O)
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
Funconcode03-Readinputholdingregister
Funconcode04-Readinputregister
Register Parameter descripon Data Type Value Range
3x0001 ParameterforP-controller 16bit 0...3 1=rH,2=TE,3=MAX
3x0003 rHreading 16bit 0...1000 0,0...100.0%
3x0004 Temp.reading 16bit 0...500 0.0...50.0°C
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 1=rH,2=TE,(3=O)
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
Funconcode05-Writesinglecoil
Register Parameter descripon Data Type Value Range
0x0001 Relaytrend Bit0 0...1 0=Increasing,1=Decreasing
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
MODBUS REGISTERS CONTINUED
Funconcode16-Writemulpleregisters
Register Parameter descripon Data Type Value Range
4x0001 ParameterforP-controller 16bit 0...3 1=rH,2=TE,3=MAX
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 1=rH,2=TE,(3=O)
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
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
recyclingsitethatspecializesinelectronicwaste.
WARRANTY POLICY
Funconcode06-Writesingleregister
Register Parameter descripon Data Type Value Range
4x0001 ParameterforP-controller 16bit 0...3 1=rH,2=TE,3=MAX
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 1=rH,2=TE,(3=O)
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
Jumper settings CONTINUED
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).