Multifunction CO2 room transmitter | CO2 400-2000ppm | T 0…50°C | 0-95%rH | 3×0-10VDC/0-20mA/PWM | Modbus RTU | 24VAC/VDC | IP30 | Sentera Controls | RSMFG-3
Code: RSMFG-3Offer is valid until 2026-12-31Price 260.86 € VAT incl.( 215.59 € VAT excl. )406.95 €You save 146.09 €Want another price? Suggest yours!-
Multifunction CO2 room transmitter | CO2 400-2000ppm | T 0…50°C | 0-95%rH | 3×0-10VDC/0-20mA/PWM | Modbus RTU | 24VAC/VDC | IP30 | Sentera Controls | RSMFG-3
The RSMFG-3 is a Sentera Controls multifunction CO2 room transmitter that measures CO2 concentration (400–2000 ppm), temperature (0…+50 °C) and relative humidity (0–95 % rH) in a room and has three analog / modulating outputs – AO1 for temperature, AO2 for humidity, AO3 for CO2 (0-10 VDC, 0-20 mA or PWM). Power supply – 24 VDC or 24 VAC ±10 %.
Key idea:
Three air quality indicators – three separate signals: the controller or BMS receives CO2, temperature and humidity separately and decides for itself how to control ventilation, heating or humidification. One device instead of three sensors.CO2 range
400–2000 ppmOutput
3 × 0-10 VDC / 0-20 mA / PWMPower supply
24 VDC or 24 VAC ±10 %Protection
IP30, indoors onlyOperating principle
The device is wall-mounted in the room (2 holes Ø 6 mm), in the occupied zone, away from doors, windows and direct exhalation. Connect the 24 VDC or 24 VAC power supply (VIN, GND), outputs AO1–AO3 with their own GND, and Modbus RTU (A, /B); the terminals are push-in, for wires up to 1.5 mm².
A self-calibrating CO2 sensor together with a temperature and humidity sensor measures air quality: AO1 outputs temperature, AO2 – relative humidity, AO3 – CO2. Output type – 0-10 VDC (≥ 50 kΩ), 0-20 mA (≤ 500 Ω) or PWM 1 kHz (3.3 or 12 VDC); all parameters are accessible via Modbus RTU, which is also used to update the firmware.
Result – the controller or BMS receives CO2, temperature and humidity as separate signals and ventilates according to the actual number of people: in an empty room ventilation runs at a minimum, and as people gather it increases, which reduces heating / cooling losses and fan energy consumption.
Benefits RSMFG-3?
Three measurements and three separate signals in one room device – fewer sensors, cables and installation work.Technical specifications
Product type Multifunction CO2 room transmitter Manufacturer / code Sentera Controls / RSMFG-3 Measured quantities CO2, temperature, relative humidity, ambient light level CO2 range 400–2000 ppm (accuracy specified up to 5000 ppm) Temperature range 0…+50 °C Humidity range 0–95 % rH, non-condensing Accuracy ±0.5 °C; ±6 % rH; CO2 ±(50 ppm + 3 % of reading) 400–2000 ppm, ±(40 ppm + 5 % of reading) 2001–5000 ppm Outputs AO1 – T, AO2 – rH, AO3 – CO2: 0-10 VDC (RL ≥ 50 kΩ) / 0-20 mA (RL ≤ 500 Ω) / PWM 1 kHz, 3.3 or 12 VDC Communication Modbus RTU (RS485); firmware update via Modbus RTU Supply voltage 24 VDC or 24 VAC ±10 % Max. current (Imax) 60 mA (DC) / 120 mA (AC) Indication Red / yellow / green LED with adjustable brightness, ambient light sensor Installation On a wall, 2 holes Ø 6 mm Protection class IP30 (EN 60529), indoor use only Weight 0.095 kg (net) Compliance LVD 2014/35/EU, EMC 2014/30/EU, WEEE 2012/19/EU, RoHS 2011/65/EU Manufacturer documentation
✔ Recommended by Elektrotechnikos sprendimaiOriginal manufacturer documentation – technical data, wiring diagrams and installation instructions.
Main functions
- Three separate outputs – T, rH and CO2 – each with its own signal to the controller or BMS.
- Modbus RTU – all measurements and settings are accessible remotely.
- Firmware update – over the Modbus RTU network.
- LED indication – green – air quality is good, yellow – warning level 1 reached, red – level 2 or value out of range.
- Light sensor – adjustable “active” and “standby” illumination levels.
- SenteraWeb – via a Sentera internet gateway – remote monitoring, log, notifications, mode schedules.
- Configuration – Configuration and monitoring – the free Sentera 3SModbus software (via the CNVT-USB-RS485 converter) or the Sensistant Modbus configurator.
Where is it used?
- Offices, meeting rooms, classrooms
- Kindergartens, schools, auditoriums
- Residential rooms and apartments
- Restaurants, gyms
- Demand-controlled ventilation with EC fans
- BMS and SenteraWeb systems
On-demand operation
For the office building HVAC designer.
Three separate T, rH and CO2 signals from a single device allow ventilation, heating and humidification to be controlled in different circuits.For the 24 VAC automation installer.
The -G version is powered from an existing 24 VAC transformer or 24 VDC.For restaurant and hall maintenance managers.
The LED with adjustable brightness shows the air quality on site when the room is crowded.Practical application
If the control panel of a meeting room has only a 24 VAC transformer and the controller expects a 0-10 VDC CO2 signal, then the RSMFG-3 is powered from the same transformer and AO3 passes CO2 within the 400–2000 ppm range.Application guide: how it is used in practice
The same RSMFG-3 adapts to different sites – only what is connected to its outputs changes:
Site What is connected Result Installer's note Air handling unit with a controller AO3 (CO2) → controller input, AO1 (T) → heating control The controller regulates airflow according to CO2 and temperature Select the signal type according to the controller input Simple DCV AO3 (CO2) 0-10 VDC → EC fan Fan speed proportional to CO2 AO1, AO2 can be used for monitoring Building with BMS Modbus RTU → A, B All three quantities in the BMS without analog cables A separate address for each device Remote monitoring Modbus RTU → Sentera internet gateway → SenteraWeb Data log, alerts, schedules A Sentera internet gateway is required How to choose a CO2 transmitter
Installation / output / power supply Recommended model Room, 3 separate outputs T / rH / CO2, 24 VDC, 4 wires RSMFF-3 (multifunction transmitter, -F) Room, 3 separate outputs T / rH / CO2, 24 VDC or 24 VAC, 3 wires RSMFG-3 (multifunction transmitter, -G) ← this model Room, 1 control output based on T / rH / CO2, 24 VDC RCMFF-3 (smart sensor, -F) Room, 1 control output, 24 VDC or 24 VAC RCMFG-3 (smart sensor, -G) Flush-mounted / surface-mounted, 1 output, powered from the 230 V mains FCMF8-R (85–264 VAC) Flush-mounted / surface-mounted, 1 output, 24 VDC or 24 VAC FCMFG-R (24 VAC/VDC) Duct, 1 control output based on T / rH / CO2, 24 VAC/VDC DCMFG-2R (smart duct sensor) Duct, NDIR CO2 + T + rH, Modbus RTU only DSCDG0-4 (no analog outputs) Duct, NDIR CO2 + T + rH, 3 analog outputs + Modbus RTU DSCDG3-4 (3 outputs) Rule: by installation location (wall, flush-mounting box, duct) and by what is needed: separate T / rH / CO2 signals for a controller or BMS (transmitter, 3 outputs), a single control signal directly to an EC fan or damper (smart sensor), or Modbus data only. Choose the supply according to the site's control circuit: -F – 24 VDC, 4-wire; -G – 24 VAC or 24 VDC, 3-wire; 8 – directly from the 230 V mains.When to choose another solution: for a single control signal without a separate controller – RCMF-3 series; for flush mounting – FCMF8-R / FCMFG-R; for a duct – DSCDG3-4; without CO2 – RSTH-3 series.Pros
- CO2, temperature and humidity in one device
- Modbus RTU, firmware updated over the network
- Three separate outputs T / rH / CO2
- Self-calibrating CO2 sensor, LED with adjustable brightness
- Compact wall-mounted housing
Cons / limitations
- CO2 measuring range 400–2000 ppm – intended for indoor air quality, not for industrial gas monitoring
- IP30 – dry rooms only
- It does not control the fan by itself – for direct control choose RCMFG-3
Safety and installation notes
- Installation and connection are to be carried out by a qualified electrician / automation specialist with the power disconnected.
- Supply voltage – 24 VDC or 24 VAC ±10 %.
- The -G version: 3-wire connection with a common ground (the analog output GND is connected to the supply GND). Never connect the common ground of the G version to devices powered by direct voltage (DC) – the connected devices may be damaged.
- Do not mix -F and -G type products on the same network.
- Resetting the Modbus communication parameters – with a jumper on PROG pins 1 and 2 for at least 5 s.
- For indoor use only; do not install in direct sunlight.
Quick selection guide
CO2 400–2000 ppm0…+50 °C0–95 % rH3 × 0-10 VDC / 0-20 mA / PWM24 VDC / 24 VACIP30Suitable when you need:- to implement demand-controlled ventilation by CO2 level;
- to pass CO2, temperature and humidity to a controller or BMS;
- to integrate air quality data into a BMS via Modbus RTU.
Check before use:- the input type of the controlled device;
- the supply: 24 VDC or 24 VAC ±10 %;
- the installation location – an occupied zone, not near doors or windows.
Important reminder: The RSMFG-3 measures CO2 to assess indoor air quality; it is not a gas leak or safety detector.FAQ
Does it measure VOC?
No, CO2, temperature, relative humidity and ambient light are measured.What are the output signals?
Each of the three outputs – 0-10 VDC, 0-20 mA or PWM, plus Modbus RTU.How are the settings changed?
Via Modbus RTU – the 3SModbus software with a CNVT-USB-RS485 converter, or via BMS.How do I reset the Modbus settings?
With a jumper on PROG contacts 1 and 2 for at least 5 seconds.What power supply does it operate from?
24 VDC or 24 VAC ±10 %.Does the transmitter control the fan itself?
No, it passes separate signals to the controller; for direct control choose RCMFG-3.Multifunction CO2 room transmitter | CO2 400-2000ppm | T 0…50°C | 0-95%rH | 3×0-10VDC/0-20mA/PWM | Modbus RTU | 24VAC/VDC | IP30 | Sentera Controls | RSMFG-3
Sentera RSMFG-3 – multifunction CO2 room transmitter: CO2 400–2000 ppm, temperature 0…+50 °C, humidity 0–95 % rH, three 0-10 VDC / 0-20 mA / PWM outputs and Modbus RTU, 24 VDC or 24 VAC ±10 % supply. For demand-controlled ventilation.
Illustrative image may have been created using AI. The appearance of the product may differ slightly from the image shown. Please refer to the technical specification.ManufacturerThis product is marked with the CE label, which confirms that it complies with all applicable European Union directives and regulations. CE marking is not just a formality – it is an important indicator of quality and safety, ensuring that the product has been properly assessed, tested, and can be safely used throughout the EU market.
CE certification means that the product has been evaluated according to the main criteria:
Safety requirements – ensures that the product does not pose a risk to the user or the environment
Electromagnetic compatibility (EMC) – the device does not interfere with other equipment and is resistant to external disturbances
Environmental standards – complies with current ecological and material usage requirements
Operational reliability – the product is suitable for long-term use according to its intended purposeCE marking allows this product to:
be legally supplied and used in all European Union countries
ensure a high level of quality and safety
be used in residential, commercial, and industrial environmentsThe CE mark is a declaration of the manufacturer’s responsibility, confirming that the product complies with all applicable standards and has been assessed according to EU legislation.
What does this mean for you as a buyer?
Safe use in everyday activities
Reliable performance and reduced risk of failure
Compliance with EU standards and requirements
Suitability for professional solutions
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