Dwyer Instruments CDTR-2D4E4 | Carbon Dioxide/RH/Temperature Transmitter | 2000 ppm CO2 range | Duct mount | 4 to 20 mA/0 to (5 or 10) VDC CO2 output | RH outputs & Pt1000 O RTD temperature output
The Dwyer Instruments CDTR-2D4E4 is a duct mount CO₂, relative humidity and temperature transmitter designed for indoor air quality and demand-controlled ventilation applications. It measures 0-2000 PPM CO₂ and 0-100% RH, with a Pt1000 Ω RTD temperature output. The transmitter provides selectable 4-20 mA, 0-5 VDC or 0-10 VDC outputs for CO₂ and RH and is housed in a NEMA 4X (IP66) duct enclosure.
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Part Number: CDTR-2D4E4
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Product Overview
The Dwyer CDTR-2D4E4 combines carbon dioxide, relative humidity and temperature measurement in a single duct-mounted device, helping reduce the number of separate sensors required in building automation and HVAC systems.
The transmitter measures CO₂ from 0 to 2000 PPM and relative humidity from 0 to 100% RH, while its Pt1000 Ω RTD provides the temperature output. This combination makes the CDTR-2D4E4 suitable for monitoring indoor environmental conditions and supplying measurement data to building management and ventilation control systems.
A single-beam, dual-wavelength NDIR sensor measures CO₂ and automatically corrects the measurement for light-source aging. The transmitter also provides digital barometric pressure adjustment and field calibration capabilities to support accurate CO₂ measurement over time.
The Digital Intelligence Temperature Compensation Algorithm (DITCA™) helps eliminate measurement error associated with self-heating in combination sensing devices. The humidity and temperature sensors are replaceable, while a physical hardware lockout helps protect configured settings.
For system integration, the CDTR-2D4E4 offers universal outputs that can be selected as 4-20 mA, 0-5 VDC or 0-10 VDC for CO₂ and RH. Current outputs support a maximum 500 Ω load, while voltage outputs require a minimum 500 Ω load.
The duct housing is rated NEMA 4X (IP66), housing only, and the transmitter supports duct air velocities from 0 to 4000 FPM (20.32 m/s). There is no integral display, but a service display tool is available for setup and calibration.
Key Benefits
- Measures CO₂, relative humidity and temperature in one duct-mounted transmitter
- 0-2000 PPM CO₂ measurement range
- 0-100% RH measurement range
- Pt1000 Ω RTD temperature output
- Single-beam dual-wavelength NDIR CO₂ sensor
- Automatic correction for CO₂ sensor light-source aging
- Digital barometric pressure adjustment and field calibration
- DITCA™ temperature compensation
- Selectable 4-20 mA, 0-5 VDC and 0-10 VDC outputs
- Replaceable humidity and temperature sensors
- Physical hardware lockout
- NEMA 4X (IP66) duct housing
- Suitable for demand-controlled ventilation and building automation systems
- Genuine Dwyer Instruments stock with free UAE-wide shipping
Who This Product Is Best For
The Dwyer CDTR-2D4E4 is suited for HVAC engineers, building automation professionals, facility managers and system integrators who need CO₂, humidity and temperature information from a single duct-mounted transmitter.
Typical applications include demand-controlled ventilation in schools, offices, hospitals and other occupied buildings, as well as projects requiring combined CO₂ and humidity monitoring, temperature measurement and building management system integration.
It can also be used in ventilation monitoring projects where indoor air quality measurements are required for energy management and building performance objectives.
How to Specify & Commission It
- Install the CDTR-2D4E4 in the duct according to the manufacturer's installation requirements.
- Connect the appropriate power supply using 16-35 VDC or 19-28 VAC.
- Wire the CO₂ and RH outputs and select 4-20 mA, 0-5 VDC or 0-10 VDC as required by the control system.
- Set the appropriate barometric pressure value and perform field calibration if required.
- Verify the CO₂, RH and temperature readings at the connected building management or HVAC controller.
- Confirm correct operation before placing the ventilation system into service.
Frequently Asked Questions
What does the Dwyer CDTR-2D4E4 measure?
The CDTR-2D4E4 measures CO₂ from 0-2000 PPM and relative humidity from 0-100% RH, with a Pt1000 Ω RTD temperature output.
What outputs are available?
The transmitter provides selectable 4-20 mA, 0-5 VDC or 0-10 VDC outputs for CO₂ and RH. Current outputs support up to 500 Ω, while voltage outputs require a minimum 500 Ω load.
What is the CO₂ accuracy?
The specified CO₂ accuracy is ±40 ppm + 3% of reading. Relative humidity accuracy is ±2%.
Does the CDTR-2D4E4 have a temperature sensor?
Yes. This model provides a Pt1000 Ω RTD temperature output.
Does the CDTR-2D4E4 have an integral display?
No. The CDTR-2D4E4 does not have an integral LCD. A service display tool is available for setup and calibration.
What type of CO₂ sensor does it use?
The transmitter uses a single-beam, dual-wavelength NDIR sensor with automatic correction for light-source aging.
Does the transmitter require recalibration?
For buildings occupied 24 hours a day, Dwyer recommends verifying calibration every 6 to 12 months, depending on the application.
What is the enclosure rating?
The duct housing is rated NEMA 4X (IP66).
What power supply does the CDTR-2D4E4 require?
It operates from 16-35 VDC or 19-28 VAC and has an average power consumption of 2 W, with a peak consumption of 3.75 W.
Is genuine Dwyer stock available with UAE shipping?
Yes. Genuine Dwyer Instruments stock is available through General Tech Services LLC with free UAE-wide shipping. Call +971 6 5436933 for pricing and current availability.
Request a Quote Today
For pricing, availability or technical assistance for the Dwyer CDTR-2D4E4 CO₂/RH/temperature transmitter, contact General Tech Services LLC.
Call: +971 6 5436933
Website: www.generaltechshop.ae
