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DWYER CDT-2D40 Carbon Dioxide Detector Transmitter - Fixed Gas Detectors with Transmitters
DWYERFixed Gas Detectors with Transmitters

DWYER CDT-2D40 Carbon Dioxide Detector Transmitter

The DWYER CDT-2D40 is a duct-mounted carbon dioxide and temperature detector transmitter for building management controllers. It measures CO₂ from 0 to 2000 ppm and operates on 16 to 35V DC or 19 to 28V AC.

SKU 3G-OTH-554844

Also listed as: CDT2D40 · CDT 2D40

Brand
DWYER
Item
CDT-2D40 Carbon Dioxide Detector Transmitter
Category
Fixed Gas Detectors with Transmitters
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

DWYER
Manufacturer Part Number
CDT-2D40
Series
CDT
Type
Carbon Dioxide, CO2
For Use With
Building Management Controllers
Gas Detected
Carbon Dioxide
Product Type
Detector Transmitter
Measurement Range
Carbon Dioxide (0 to 2000 ppm)
Mounting Location
Duct
Operating Voltage
16 to 35V DC/19 to 28V AC
Includes Calibration Certificate
No

Datasheet Content

AIR QUALITY SERIES CDT CARBON DIOXIDE/TEMPERATURE TRANSMITTERS NDIR CO2 Sensor, Universal Outputs, Optional Relay YEAR LIMITED WARRANTY 1.10 [27.96] .552 [14.02] 2x .176 [4.47] 4.50 3.000 [114.30] [76.20] .573 [14.56] 2.80 [71.12] 11-49/64˝ 4-25/32˝ [298.85] 1/8˝ [121.44] [3.17] 4-9/32˝ [108.74] 2-13/16˝ North American style DSA* compliant option -S Duct [71.44] Ø1-15/64˝ [31.35] VIDEO ON NE Ø3-5/16˝ LI [84.14] *Division of the State Architect - California The Series CDT Carbon Dioxide and Temperature Transmitters accurately monitor SPECIFICATIONS the CO2 concentration and temperature in indoor environments to help achieve energy savings. In order to achieve a higher level of accuracy, the Series CDT includes Sensor: NDIR, 15 year life expectancy. barometric pressure adjustment. The CO2 universal output allows users to select the Range: CO2: 0 to 2000 or 0 to 5000 PPM (depending on model); Temperature: 32 transmitter output to be 4-20 mA, 0-5 VDC, or 0-10 VDC to work with virtually any to 122°F (0 to 50°C). building management controller. Accuracy**: CO2: ±40 PPM + 3% of reading (2000 PPM CO2); ± 50 PPM + 5% of For applications that require visual indication, the wall mount configurations of the reading (5000 PPM CO2); Temperature: ±1°C @ 25°C. Series CDT can be ordered with an integral LCD display. To prevent tampering, the Response Time: 2 min for 90% step change. action of the buttons can be locked out using an internal dip switch selection. Temperature Limits: 32 to 122°F (0 to 50°C). The Series CDT CO2 transmitters are available with a -S option that provides the Humidity Limits: 0 to 85% (non-condensing). necessary attributes and parameters to be compliant with DSA requirements for Power Requirements: 16-35 VDC or 19-28 VAC. monitoring CO2 levels in schools. There is a front facing LED that illuminates when the Power Consumption: Average: 2 w; Peak: 3.75 w. CO2 level exceeds 1100 PPM. Output: Current: 4-20 mA (max. 500 Ω); Voltage: 0-5 VDC or 0-10 VDC (min. 500 Ω); Relay: SPST NO rated 2A @ 30 VDC; RTD or thermistor per r-t curves on page BENEFITS/FEATURES 4 (depending on model). • Minimize inventory and save time by combining CO2 and temperature Compliance: CE. Carbon Dioxide measurements into one transmitter **The specified CO2 accuracy is only guaranteed after three weeks of continuous • Reduces the number of devices mounted in the space with integral humidity and operation in environments which are intermittently occupied. temperature sensors Transmitters • Requires minimal maintenance with Automatic Baseline Correction (ABC) to account for sensor drift • Reduce operation costs using a low energy, reliable, and repeatable CO2 sensor • Simplify installation with backplate electrical connection APPLICATIONS • Demand control ventilation in schools, office buildings, hospitals, and other indoor environments • LEED® certification MODEL CHART ACCESSORIES Example CDT -2 N 4 4 -LCD CDT-2N44-LCD Model Description Series CDT Carbon dioxide/temperature transmitter A-449 Remote LCD display allows remote indication of Range 2 0 to 2000 PPM CO2 range select Dwyer® wall mount transmitters for validation or 5 0 to 5000 PPM CO2 range certification purposes A-449A Remote LCD display with buttons allows remote indication Configuration N North American style wall mount and calibration of select Dwyer® wall mount transmitters for D Duct mount validation and certification purposes CO2 4 4-20 mA / 0 to (5 or 10) VDC Temperature 0 None Output 4 4-20 mA / 0 to (5 or 10) VDC A 10 KΩ NTC thermistor type III B 10 KΩ NTC thermistor type II D Pt100 Ω RTD E Pt1000 Ω RTD F 20 KΩ NTC thermistor Options FC Factory calibration certificate LCD LCD display (wall only) RLY Relay S School A-449 A-449A LEED® is a registered trademark of the U.S. Green Building Council DWYER INSTRUMENTS, LLC | dwyer-inst.com 227

Technical Documents

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DWYER Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The DWYER CDT-2D40 is a duct-mounted carbon dioxide and temperature detector transmitter for building management controllers. It measures CO₂ from 0 to 2000 ppm and operates on 16 to 35V DC or 19 to 28V AC.

Frequently Asked Questions

What is the DWYER CDT-2D40 used for?

The DWYER CDT-2D40 is a duct-mounted carbon dioxide and temperature detector transmitter used with building management controllers to monitor indoor air quality. It measures CO₂ from 0 to 2000 ppm and helps optimize HVAC ventilation in commercial facilities.

What are the specifications of the DWYER CDT-2D40?

The DWYER CDT-2D40 operates on 16 to 35V DC or 19 to 28V AC, detects carbon dioxide from 0 to 2000 ppm, and mounts in a duct. It is designed for use with building management controllers and is part of the DWYER CDT series.

Where to buy the DWYER CDT-2D40 worldwide?

3G Electric supplies the DWYER CDT-2D40 worldwide, handling full logistics and customs clearance. As a global industrial solutions provider, we source and deliver this CO₂/temperature transmitter to building management projects across all regions.

How to install the DWYER CDT-2D40?

Install the DWYER CDT-2D40 in a duct location with proper airflow, following the manufacturer's wiring diagram for 16 to 35V DC or 19 to 28V AC power. Ensure the sensor is accessible for periodic calibration and verify output signals to the building management controller.

Used in

Common applications for DWYER
Combustion air-filter monitoring — Magnehelic Series 2000 on burner air-intake filter banks
Clean-room and pharmaceutical pressurisation — Magnehelic / Capsuhelic differential-pressure gauges
HVAC fan-discharge static pressure — Mark II inclined-vertical manometers on AHU test points
Filter-blockage alarms — Photohelic Series 3000 combined gauge/switch on air-handling units
BMS-integrated pressure monitoring — Digihelic DH3 with 4–20 mA output for building management

DWYER Products

3G Electric supplies DWYER fixed gas detectors with transmitters. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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