User Manual

TSM400-4-CPTH_R1.0 – August 2022 Page 2
1. Short description
TSM400-4-CPTH is a multi-sensor that supports MODBUS RTU protocol over the RS-485 interface.
The sensor measures CO
2
concentration, temperature, humidity, and barometric pressure. The
MODBUS device integrates an advanced non-dispersive infrared sensing element (NDIR) for CO
2
measurements. The measurement principle is based on the absorption of infra-red (IR) light with
specific wavelengths by CO
2
molecules. The carbon dioxide sensing element is temperature
compensated for better accuracy. Self-calibration is available for carbon dioxide measurements. It is
done if the sensor is left in fresh (around 400 ppm CO
2
concentration) air.
The basic sensing element for barometric pressure is factory calibrated and it does not require any
lifetime recalibration. A unique capacitive element is used for measuring relative Humidity while the
temperature is measured by a band gap sensor. Both sensors are seamlessly coupled to a 12-bit
analog to digital-converter. This results in superior signal quality.
The TSM400-4-CPTH multi-sensor is housed in a slim plastic enclosure. The bottom part of the
enclosure is suitable for installation on standard flush-mounted/cavity wall boxes ø68mm, with
installation openings on 61 mm.
2. Features
• LED indicator for status of communication;
• Long-term stability based on digital signal processing;
• Self-calibration on fresh air for CO
2
measurements;
• RS-485 interface carrying up to 32 nodes;
• Changeable bitrate and other communication parameters;
• Firmware update via the interface.
3. Applications
•
Environmental quality monitoring and assessment for offices
•
CO
2
pollution monitoring
•
Server room and data centers humidity and temperature monitoring
•
Smart ventilation systems
•
CO
2,
humidity, and temperature monitoring in building management systems (BMS)
4. Specifications
•
Physical characteristics
Dimensions: 81 x 81 x 30 mm
Weight: 66 g
•
Environmental limits
Operating temperature range: -20 to 60°C
Operating relative humidity range: 5 to 95% (non-condensing)
Storage temperature range: -20 to 60°C
Storage relative humidity range: 5 to 95% (non-condensing)
Ingress protection: IP20
•
Power requirements
Operating voltage range (including -15/+20% according to IEC 62368-1): 4.5 to 26 VDC
Current consumption: 25 mA@5VDC (Peak: 150 mA@5VDC)