Series CDT and CDTR Duct Mount Carbon Dioxide/Temperature/Relative Humidity TransmitterSpecifications - Installation and Operating InstructionsBulletin AQ-CDT/CDTRSeries CDT and CDTR Duct Mount Carbon Dioxide/ Temperature/Relative Humidity Transmitters accurately monitor the CO2 concentration and temperature in schools, office buildings, and other indoor environments to help achieve LEED® certification. For increased sensor life, a single- beam dual-wavelength non-dispersive infrared (NDIR) sensor is used to automatically correct the measurement in both occupied and unoccupied buildings against aging effects. The single-beam dual-wavelength sensor technology provides the highest level of accuracy, compared to Automatic Baseline Correction methods, which can unintentionally shift the calibration based on CO2 levels and barometric pressure conditions. In order to achieve a higher level of accuracy, the Series CDT includes digital barometric pressure adjustment and the ability to field-calibrate the sensor.Universal outputs allow users to select the transmitter output to be 4 to 20 mA, 0 to 5 VDC or 0 to 10 VDC to work with virtually any building management controller. An optional relay with user adjustable set points can be used to control exhaust fans, open actuated windows or dampers, or signal a light or horn.For applications that require visual indication, the Series CDT and CDTR can be ordered with the Model A-449 remote LCD display that can plug into the mini-connector port on the internal circuit board. Both the CDT and CDTR can be configured to display temperature only, CO2 only or CO2 and temperature together. The CDTR can also display relative humidity or CO2 and relative humidity together. Menu items that can be accessed include: engineering units, relay output set points, display configuration, transmitter output scaling, ambient barometric pressure and field calibration of the transmitter.Single-beam dual-wavelength sensor advantages:• Automatically corrects for aging effects in occupied and unoccupied buildings ◦ Perfect for hospitals and manufacturing plants that are occupied 24 hours per day• Measures actual unfiltered light intensity directly ◦ Eliminates error from incorrect assumptions of gas concentration in theoretical logic assumption methodsINSTALLATIONLEED® is a registered trademark of the U.S. Green Building CouncilDisconnect power supply before installation to prevent electrical shock and equipment damage.Make sure all connections are in accordance with the job wiring diagram and in accordance with national and local electrical codes. Use copper conductors only.Use electrostatic discharge precautions (e.g., use of wrist straps) during installation and wiring to prevent equipment damage.Avoid locations where severe shock or vibration, excessive moisture or corrosive fumes are present.Do not exceed ratings of this device, permanent damage not covered by warranty may result.Upon powering the transmitter, the firmware version will flash on the display. A warm up period of 30 minutes is required for the transmitter to adjust to the current CO2 concentration.Self calibration feature of the transmitter requires exposure to normal outdoor equivalent carbon dioxide level once every thirty days.NOTICENOTICESPECIFICATIONSRange: CO2: 0 to 2000 or 0 to 5000 ppm (depending on model); RH: 0 to 100% (for units configured with humidity output); Temperature: 32 to 122°F (0 to 50°C).Accuracy: ±40 ppm + 3% of reading (CO2); RH: ±2% (for units configured with humidity output); Temperature: ± 1°C @ 25°C.Temperature Dependence: ±8 ppm / °C at 1100 ppm.Non-Linearity: 16 ppm.Pressure Dependence: 0.13% of reading per mm of Hg.Response Time: 2 minutes for 99% step change.Temperature Limits: 32 to 122°F (0 to 50°C).Humidity Limits: 10 to 95% RH (non-condensing).Power Requirements: 16 to 35 VDC / 19 to 28 VAC.Power Consumption: Average: 2 watts; Peak: 3.75 watts.Sensor: Single-beam, dual-wavelength NDIR.Output: Current: 4 to 20 mA (max 500 Ω); Voltage: 0 to 5 VDC or 0 to 10 VDC (min 500 Ω); Relay: SPST NO 2A @ 30 VDC; RTD or thermistor per r-t curves (depending on model).Weight: 5.6 oz (158.8 g).Agency Approvals: CE.WARNINGCAUTIONCAUTIONCAUTION1/8˝[3.17]4-25/32˝[121.44]4-9/32˝[108.74]2-13/16˝[71.44]Ø3-5/16˝[84.14]11-49/64˝[298.85]Ø1-15/64˝[31.35]®DWYER INSTRUMENTS, INC.P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.Phone: 219/879-8000Fax: 219/872-9057www.dwyer-inst.come-mail: info@dwyermail.comMOUNTING1. Cut hole into duct large enough to insert probe.2. Attach housing ears to duct using the two self-tapping screws provided.3. Knock out an opening in the housing and attach an electrical fitting to route electrical wiring. PG11 & PG16 knockouts are molded into the housing.WIRINGUse maximum 18 AWG wire for wiring to terminals. Refer to Figure 5 for wiring information.Selection of Current and Voltage OutputsPrior to wiring, verify that the current/voltage configuration switches (positions 1 and 2) are set to the desired output type. Refer to Figure 1 to locate the configuration switches. See Figure 2 for diagram of the current/voltage selection switches. For voltage output selection, the output can be 0 to 10 VDC, 0 to 5 VDC, 2 to 10 VDC or 1 to 5 VDC. See Figure 3 for the type of voltage output selection switches (positions 3 & 4).Current / Voltage OutputsThe transmitter may be wired for current or voltage output for both carbon dioxide and temperature. The transmitter can be powered with either 16 to 35 VDC or 19 to 28 VAC. Wire the transmitter according to Figure 4. Thermistor and RTD OutputsThermistor and RTD passive outputs are located on terminals 7 and 8 and do not require any power. Passive temperature outputs are not polarity sensitive.Remote DisplayRemote display Model A-449 can be used to display the relative humidity, temperature, and carbon dioxide. The mini USB plug of the remote display plugs into the receptor on the side of the housing. After a short warm up time, the display will begin to show the current temperature and carbon dioxide measurements unless configured by the user to show only temperature or only carbon dioxide.ACCESSING MENU PARAMETERSStep 1: To enter the menu structure, press and simultaneously for 5 seconds (display will show RON parameter).Step 2: Press or to cycle between menu items. Step 3: Press to edit the value for the displayed menu item (SET will appear on display).Step 4: Press or to adjust the value of the menu item.Step 5: Press to save the changes (SET will disappear).Step 6: Repeat Steps 2 through 5 for each of the parameters.Step 7: To exit the menu at any time, press and hold and simultaneously for 5 seconds or wait 10 seconds without pushing any buttons.PASSIVETEMPERATURESENSORRELAYCONTACTPOWERSUPPLYTEMP OR RHRECEIVERCO2RECEIVERFigure 4: Active output wiring diagramFigure 1: Diagram of circuit boardFigure 2: Current/Voltage OutputSelection Jumper (PJ1 And PJ2)Figure 3: Output range selection jumperOptional relay can be used as either a dry contact or low voltage switched circuit up to 2 A at 30 VDC.NOTICEDOWN PUSHBUTTONCONFIGUATIONSWITCHESTERMINALBLOCKREMOTE DISPLAYCONNECTORUP PUSH BUTTONENTER PUSH BUTTONCO2 CONCENTRATIONOUTPUT SELECTIONTEMPERATURE/RH OUTPUT SELECTIONVOLTAGECURRENTVOLTAGECURRENT0-10 V0-20 mA2-10 V4-20 mA0-5 V0-10 mA1-5 V2-10 mARelay on set pointSets the CO2 concentration which the optional relay is energized.Low limit: 0 PPMFactory setting: 1000 PPMHigh limit: 2000/5000 PPM (depending on model)Relay off set pointSets the CO2 concentration which the optional relay is de-energized. Setting value lower than RON provides direct action for detecting high concentrations of CO2. Setting value higher than RON provides indirect action for detecting low concentrations of CO2. or on the LCD display will be lit to indicate when the relay is energized. Low limit: 0 PPMFactory setting: 950 PPMHigh limit: 2000/5000 PPM (depending on model)Display configurationDetermines the LCD display configuration during normal operation. The LCD display can indicate the CO2 concentration, temperature, relative humidity (CDTR only) and CO2 concentration combined with temperature or relative humidity (CDTR only).CH CO2 concentration and relative humidity (CDTR only)CT CO2 concentration and temperatureC CO2 concentration onlyT Temperature onlyH Relative humidity only (CDTR only)Units selectionTemperature and barometric pressure measurements can be displayed in US engineering units or SI engineering units. The factory default is to display US engineering units.US units °F for temperature and in Hg for barometric pressureSI units °C for temperature and hPa for barometric pressureCO2 low output rangeSets the CO2 concentration for the lowest output (4 mA or 0 VDC).Low limit: 0 PPMFactory setting: 0 PPMHigh limit: 2000/5000 PPM (depending on model)CO2 high output rangeSets the CO2 concentration for the highest output (20 mA, 5 VDC or 10 VDC). When COH is set above COL, the transmitter is direct acting and the output will increase with an increase in CO2 level. When COH is below COL, the transmitter is reverse acting and the output will increase with a decrease in CO2 level.Low limit: 0 PPMFactory setting: 2000/5000 PPM (depending on model)High limit: 2000/5000 PPM (depending on model)RON ROFDSPUNICOLCOHTOLTOHHOLHOHBARCALTemperature low output range (CDT with active temperature only)Sets the temperature for the lowest output (4 mA or 0 VDC).Low limit: 32.0°F / 0.0°CFactory setting: 32.0°F / 0.0°CHigh limit: 122.0°F / 50.0°CTemperature high output range (CDT with active temperature only)Sets the temperature for the highest output (20 mA, 5 VDC or 10 VDC). When TOH is set above TOL, the transmitter is direct acting and the output will increase with an increase in temperature. When TOH is below TOL, the transmitter is reverse acting and the output will increase with a decrease in temperature.Low limit: 32.0°F / 0.0°CFactory setting: 122.0°F / 50.0°CHigh limit: 122.0°F / 50.0°CHumidity low output range (CDTR only)Sets the temperature for the lowest output (4 mA or 0 VDC).Low limit: 0.0%Factory setting: 0.0%High limit: 100.0%Humidity high output range (CDTR only)Sets the temperature for the highest output (20 mA, 5 VDC or 10 VDC).When HOH is set above HOL, the transmitter is direct acting and the output will increase with an increase in temperature. When HOH is below HOL, the transmitter is reverse acting and the output will increase with a decrease in temperature.Low limit: 0.0%Factory setting: 100.0%High limit: 100.0%Barometric pressureSets the typical barometric pressure for the location where the transmitter is mounted. The factory setting is for standard pressure at sea level. Adjusting the barometric pressure gives a more accurate measurement, especially at higher elevations. Refer to the elevation charts in Figure 9 for typical barometric pressures at a given elevation.Low limit: 20.0 in Hg / 600 hPaFactory setting: 29.9 in Hg / 1013 hPaHigh limit: 32.0 in Hg / 1100 hPaCalibrationCalibrates the carbon dioxide sensor to a known gas value. Read calibration instructions before using this feature. Hold for 5 seconds.Menu Descriptions©Copyright 2019 Dwyer Instruments, Inc.Printed in U.S.A. 4/19FR# 443800-10 Rev. 9CALIBRATING SENSOR Step 1: Remove the cover as shown in Figure 1. Step 2: Slide the calibration tubing through the slots on the back plate and attach to one of the nipples on the CO2 sensor (See Figure 7).Step 3: Carefully re-attach the cover to the back plate without pinching the tubing between the back plate and the cover.Step 4: Follow the steps in the accessing parameter section to access the calibration parameter (CAL).Step 5: Press the button.Step 6: Flow zero reference gas at 0.3 SLPM for 5 minutes.Step 7: Press and hold the button for 3 seconds.Step 8: Flow the full scale reference gas at 0.3 SLPM for 5 minutes.Step 9: Press and hold the button for 3 seconds.Step 10: Exit the parameter menu.Step 11: Remove cover as shown in Figure 1.Step 12: Remove tubing from sensor and re-attach the gas nipple cover to the sensor.Step 13: Re-attach the cover to the back plate.MAINTENANCE/REPAIRUpon final installation of the Series CDT/CDTR, no routine maintenance is required. The Series CDT/CDTR is not field serviceable and should be returned if repair is needed. Field repair should not be attempted and may void warranty.WARRANTY/RETURNRefer to “Terms and Conditions of Sales” in our catalog and on our website. Contact customer service to receive a Return Goods Authorization number before shipping the product back for repair. Be sure to include a brief description of the problem plus any additional application notes.SeriesCDT-2D44-RLYExample: CDT-2D44-RLYRange250 to 2000 ppm CO2 range0 to 5000 ppm CO2 rangeConfigurationDDuctCO2 Output44 to 20 mA / 0 to (5 or 10) VDCTemperature Output04ABC DEFNone4 to 20 mA / 0 to (5 or 10) VDC10 KΩ NTC thermistor type III10 KΩ NTC thermistor type II3 KΩ NTC thermistorPt100 Ω RTDPt1000 Ω RTD20 KΩ NTC thermistorOptionsRLYRelayUS Customary Unitsftin Hg040080012001600200024002800320036004000440048005200560060006400680072007600800084008800920096001000029.9229.5029.1028.6928.2927.9027.5127.1326.7626.3926.0225.6625.3024.9524.6024.2623.9323.6023.2722.9422.6322.3122.0021.7021.4021.40SI UnitsmhPa0100200300400500600700800900100011001200130014001500160017001800190020002100220023002400250010131002990979968957946935924914904893883873863853844834824815806797787779770761SeriesCDTR-2D4A4-RLYExample: CDTR-2D4A4-RLYRange250 to 2000 ppm CO2 range0 to 5000 ppm CO2 rangeConfigurationDDuctCO2 Output44 to 20 mA / 0 to (5 or 10) VDCTemperature Output0ABCDEFNone10 KΩ NTC thermistor type III10 KΩ NTC thermistor type II3 KΩ NTC thermistorPt100 Ω RTDPt1000 Ω RTD20 KΩ NTC thermistorRH Output44 to 20 mA / 0 to (5 or 10) VDCOptionsRLYRelayTemperatureResistance Curves (in Ohms)°C°FABCDEF-55-50-45-40-35-30-25-20-15-10-505101520253035404550556065707580859095100105110115120125130135140145150-67.0-58.0-49.0-40.0-31.0-22.0-13.0-4.05.014.023.032.041.050.059.068.077.086.095.0104.0113.0122.0131.0140.0149.0158.0167.0176.0185.0194.0203.0212.0221.0230.0239.0248.0257.0266.0275.0284.0293.0302.0607800.00441200.00323600.00239700.00179200.00135200.00102900.0078910.0061020.0047540.0037310.0029490.0023460.0018780.0015130.0012260.0010000.008194.006752.005592.004655.003893.003271.002760.002339.001990.001700.001458.001255.001084.00939.30816.80712.60623.60547.30481.80425.30376.40334.00297.20265.10237.00963849.00670166.00471985.00336479.00242681.00176974.00130421.0097081.0072957.0055329.0042327.0032650.0025392.0019901.0015712.0012493.0010000.008057.006531.005326.004368.003602.002986.002488.002083.001752.001480.001255.001070.00915.50786.60678.60587.60510.60445.30389.60341.90301.00265.80235.30208.90186.10289154.70201049.80141595.50100943.7072804.3053092.2039126.3029124.3021887.1016598.7012698.109795.007617.605970.304713.603747.903000.002417.101959.301597.801310.401080.60895.80746.40624.90525.60444.00376.50321.00274.65235.98203.58176.28153.18133.59116.88102.5790.3079.7470.5962.6755.8378.3280.3182.2984.2786.2588.2290.1992.1694.1296.0998.04100.00101.95103.90105.85107.79109.74111.67113.61115.54117.47119.40121.32123.24125.16127.08128.99130.90132.80134.71136.61138.51140.40142.29144.18146.07147.95149.83151.71153.58155.46157.33783.2803.1822.9842.7862.5882.2901.9921.6941.2960.9980.41000.01019.51039.01058.51077.91097.41116.71136.11155.41174.71194.01213.21232.41251.61270.81289.91309.01328.01347.11366.11385.11404.01422.91441.81460.71479.51498.31517.11535.81554.61573.32394000.001646200.001145800.00806800.00574400.00413400.00300400.00220600.00163500.00122280.0092240.0070160.0053780.0041560.0032340.0025360.0020000.0015892.0012704.0010216.008264.006722.005498.004520.003734.003100.002586.002166.001822.601540.001306.401112.60951.00815.80702.20606.40525.60N/AN/AN/AN/AN/AFigure 5: CDT model chartFigure 7: Elevation chartFigure 8: Resistance vs temperatureRESISTANCE VS TEMPERATURE TABLEFigure 6: CDTR model chartThis symbol indicates waste electrical products should not be disposed of with household waste. Please recycle where facilities exist. Check with your Local Authority or retailer for recycling advice.DWYER INSTRUMENTS, INC.P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.Phone: 219/879-8000Fax: 219/872-9057dwyer-inst.come-mail: info@dwyermail.comNext >