CO/CO2/Temperature/Humidity/Dew Point Data Logger

The DL-300 series of Data Logger devices can be used to record CO, CO2, Temperature, Humidity and Dew Point information, including date and time stamps, and are able to store up to 450,000 downloadable records.

Real-time data can be accessed from the DL-300 Data Logger from anywhere and at any time using the free Windows software, the iOS App or the Android App.

Support is provided for popular industrial protocols such as DCON, Modbus RTU, and Modbus TCP, as well as the emerging machine-to-machine (M2M)/)IoT (Internet of Things) connectivity protocol – MQTT. The DL-300 Data Logger can be connected via widely used communication interfaces including RS-485, Ethernet and PoE, meaning that the device can be easily integrated into existing HMI or SCADA systems, and is easy to be maintained in a distributed control system.

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  • Simultaneous Display for CO, CO2, Temperature, Humidity and Dew Point
  • Measurement Range
    • CO: 0 ~ 1000 ppm
    • CO2: 0 ~ 9999 ppm
  • Non-dispersive Infrared (NDIR) CO2 Sensor
  • 2.8″ LCD Touch Screen
  • Able to store up to 450,000 records with date and time stamps
  • Touch-screen and Web-based Configuration Interfaces
  • Free Software Utility, iOS App and Android App Included
  • Able to Display Multilingual Messages
  • Supports the DCON, Modbus RTU, Modbus TCP and MQTT Protocols
  • Includes RS-485/Ethernet/PoE Communication Interfaces
  • Relay Output for Alarm Device or IAQ Device Control
  • Desktop, DIN-Rail or Wall Mounting
  • Transportation of Food or Pharmaceuticals
  • Food and Beverage Industry (HACCP)
  • Blood Stations and Pharmacies
  • Building and Energy Management
  • Warehouse Management
  • Museums, Archives and Galleries



Models DL-301 DL-302 DL-303
CO Measurement
Range 0 to 1000 ppm (Electrochemical) 0 to 1000 ppm (Electrochemical)
Resolution 1 ppm 1 ppm
Accuracy ±5% of measured value ±5% of measured value
Response Time 30 seconds 30 seconds
Warm-up Time 300 seconds 300 seconds
CO2 Measurement
Range 0 to 9999 ppm (NDIR)
Resolution 1 ppm
Accuracy ±30 ppm ±3% of measured value
Response Time 20 seconds
Warm-up Time 60 seconds
Temperature Measurement
Range -10 to +50°C
Resolution 0.1°C
Accuracy ±0.6°C
Relative Humidity Measurement
Range 0 to 100% RH
Resolution 0.1% RH
Accuracy ±5% RH
Dew Point
Range Calculated using temperature and relative humidity
Resolution 0.1°C
CO Alarm Yes Yes
CO2 Alarm Yes Yes
Real Time Clock Yes
Data Logger Yes, up to 450,000 records
Relay Output Form A×1, SPST
30 VDC @ 16 A or 250 VAC @ 16 A
Interface RS-485/Ethernet/PoE
Main Machine Interface
LCD 2.8 TFT (Resolution 240 x 320 x 16), Defective Pixels <= 3
Backlight Life 20,000 hours
Brightness 160 cd/m2
Touch Panel Yes
Powered from Terminal Block +12 to +48 VDC
Powered from PoE IEEE 802.3af, Class 1 (48 V)
Power Consumption PoE 1.84 W (Max.) 2.65 W (Max.) 2.83 W (Max.)
Non-PoE 1.74 W (Max.) 2.14 W (Max.) 2.24 W (Max.)
Dimensions (L x W x H) 114 mm x 106 mm x 56 mm
Installation Desktop, DIN-Rail or Wall Mounting
Operating Temperature 0 to +50°C
Storage Temperature -30 to +75°C
Humidity 10 to 90% RH, Non-condensing


Large 2.8″ LCD Touch Screen, with clear Color Chart to indicate the CO/CO2 Level

Supports the MQTT Protocol for IoT Applications

Powerful, Free DL300 Utility Software

The DL300 Utility can be used to configure the modules, monitor real-time data, group DL-300 modules so that the status of distribution groups can be viewed and managed. The utility also allows the log data to be downloaded and exported to a .CSV file that can then be imported into any industry-standard software or spread sheet for analysis.

Display Messages in Multiple Languages

The display-message-on-screen function supports multiple language character sets based on UTF-8 encoding. Users can remotely display either pre-configured messages or dynamic messages to prompt an operator with a daily schedule or IAQ device control instructions.

Ordering Information

DL-301 CR Remote CO/Temperature/Humidity/Dew Point Data Logger with Safety Alarm (RoHS)
DL-302 CR Remote CO2/Temperature/Humidity/Dew Point Data Logger with Safety Alarm (RoHS)
DL-303 CR Remote CO/CO2/Temperature/Humidity/Dew Point Data Logger with Safety Alarm (RoHS)


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