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  • New item   -48.67€Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2
    New item   -48.67€Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2 1
    New item   -48.67€Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2 2
    New item   -48.67€Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2 3
    New item   -48.67€Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2 4

    Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2

    Code: RCTHF-2
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  • Product description

    Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2

    The RCTHF-2 is a Sentera Controls smart room temperature and humidity sensor-controller: it measures temperature (0…+50 °C) and relative humidity (0–95 % rH) in a room and, using the integrated algorithm, generates a single analog / modulating output (0-10 VDC, 0-20 mA or PWM) that can directly control an EC fan, an AC fan speed controller or a damper actuator. Power supply – 18–34 VDC; all parameters are accessible via Modbus RTU.

    Key idea:
    This is a transmitter and a controller in one: it needs no separate controller, because the output is calculated in the sensor itself according to the set temperature and humidity ranges. The output is determined by the higher of the two values, and either parameter can be disabled – e.g. to control by temperature only or by humidity only.
    Measurement
    0…+50 °C / 0–95 % rH
    Control output
    0-10 VDC / 0-20 mA / PWM
    Power supply
    18–34 VDC
    Protection
    IP30, indoors only

    Operating principle

    The sensor is fixed to a wall in the room (2 holes of Ø 6 mm) and wired with 4 wires with separate grounds: supply 18–34 VDC (VIN, GND), control output AO1 with its own GND and Modbus RTU (A, /B).

    Integrated sensors measure temperature and relative humidity; a range is set for each quantity within which the output varies 0–100 %, the output is determined by the higher of the two calculated values, and either quantity can be disabled. The output type is selectable – 0-10 VDC (≥ 50 kΩ), 0-20 mA (≤ 500 Ω) or 1 kHz PWM (open collector, 3.3 or 12 VDC) – and it directly controls an EC fan, an AC fan speed controller or a damper actuator; all parameters are changed over Modbus RTU, and the firmware is updated over the network.

    Result – demand-controlled ventilation without a separate controller: as humidity or temperature rises the fan speeds up, and when it falls it slows down to the minimum, while the three-colour LED and light sensor inform the user on site.

    Benefits RCTHF-2?
    Sensor and control algorithm in one – less equipment in the control panel, a simpler design and faster commissioning, while Modbus RTU allows later integration into a BMS.

    Technical specifications

    Product type Smart room temperature and humidity sensor-controller
    Manufacturer / code Sentera Controls / RCTHF-2
    Series RCTH-2 (RCTHF-2 / RCTHG-2 / RCTHH-2)
    Measured quantities Temperature, relative humidity, ambient illuminance
    Temperature range 0…+50 °C
    Humidity range 0–95 % rH, non-condensing
    Accuracy ±0.4 °C (0…+50 °C); ±3 % rH
    Control logic Output based on the higher of the T and rH values; each parameter can be disabled
    Analog output 1 × 0-10 VDC (RL ≥ 50 kΩ) / 0-20 mA (RL ≤ 500 Ω) / PWM 1 kHz, open collector, 3.3 or 12 VDC
    Communication Modbus RTU (RS485), A, /B; firmware update via Modbus RTU
    Supply voltage 18–34 VDC
    Max. current (Imax) 40 mA
    Connection 4-wire, separate grounds (-F)
    Indication Red / yellow / green LED, ambient light sensor
    Installation On a wall, 2 holes Ø 6 mm
    Protection class IP30 (EN 60529), indoor use only
    Weight 0.075 kg (net)
    Compliance LVD 2014/35/EU, EMC 2014/30/EU, WEEE 2012/19/EU, RoHS 2011/65/EU

    Manufacturer documentation

    ✔ Recommended by Elektrotechnikos sprendimai

    Original manufacturer documentation – technical data, wiring diagrams and installation instructions.

    Main functions

    • Integrated control algorithm – the output is generated according to the set T and rH ranges, without a separate controller.
    • Parameters that can be disabled – can be controlled by temperature only or humidity only.
    • Direct control – An EC fan, AC speed controller or damper actuator is connected directly to the output.
    • Modbus RTU – all parameters and measurements are accessible remotely; Modbus timeout (HR8) monitoring.
    • Firmware update – over the Modbus RTU network.
    • LED indication – red – value out of range or sensor fault, yellow – danger zone or Modbus connection lost, green – normal.
    • Light sensor – adjustable “active” and “standby” illumination levels – e.g. for quieter operation at night.
    • Configuration – Configuration and monitoring – the free Sentera 3SModbus software (via the CNVT-USB-RS485 converter) or the Sensistant Modbus configurator.

    Where is it used?

    • Bathrooms, showers, laundries
    • Offices, classrooms, residential rooms
    • Warehouses and archives
    • Systems with EC fans or dampers
    • BMS with Modbus RTU
    • Office meeting rooms with demand-controlled ventilation
    • Apartment bathrooms with an extract EC fan

    On-demand operation

    For the office demand-controlled ventilation designer.
    The sensor itself calculates the control signal from the higher of the T and rH values, so the room needs no separate controller.
    For the 24 VDC automation installer.
    The -F version is wired with 4 wires with separate grounds, so the control signal stays stable on long lines.
    For school facility managers.
    A three-colour LED in the classroom shows the microclimate status without connecting to the system.

    Practical application

    If the EC fan of a meeting room has a 0-10 VDC input and the panel has a 24 VDC supply, then the RCTHF-2 is connected directly to the fan and, as humidity or temperature rises within the set range, increases its speed up to 100 %.

    Application guide: how it is used in practice

    The same RCTHF-2 adapts to different sites – only what is connected to its output changes:

    Site What is connected Result Installer's note
    Bathroom, shower, laundry AO1 0-10 VDC → EC fan control input As humidity rises, extraction automatically increases; when it falls, it returns to the minimum Temperature can be disabled – control by rH only
    Warehouse, workshops AO1 → AC fan speed controller analog input On a hot day extraction increases with temperature Select the signal type according to the regulator input
    System with an air damper AO1 → damper actuator 0-10 VDC input The damper opens in proportion to humidity or temperature Check the actuator input resistance (≥ 50 kΩ for voltage mode)
    Building with BMS Modbus RTU → A, /B Settings and status are accessible centrally A separate address for each sensor

    How to choose a room temperature and humidity transmitter

    Installation / output / power supply Recommended model
    Wall, 3 analog outputs, 18–34 VDC, 4-wire RSTHF-3 (room transmitter, -F)
    Wall, 3 analog outputs, 18–34 VDC or 15–24 VAC, 3-wire RSTHG-3 (room transmitter, -G)
    Wall, Modbus RTU only, PoM, RJ45 RSTHM-2 (room Modbus sensor)
    Wall, Modbus RTU + wall surface temperature (dew point control), PoM RWTHM-2 (with surface temperature sensor)
    Wall, direct control with 1 output, 18–34 VDC RCTHF-2 (smart room, -F) ← this model
    Wall, direct control with 1 output, 18–34 VDC or 15–24 VAC RCTHG-2 (smart room, -G)
    Wall, direct control with 1 output, 24 VDC via RJ45 (PoM) or terminals RCTHH-2 (smart room, PoM)
    Flush-mounted / surface-mounted, 1 output, powered directly from the 230 V mains FCTH8 (85–264 VAC)
    Flush-mounted / surface-mounted, 1 output, 18–34 VDC FCTHF (-F)
    Flush-mounted / surface-mounted, 1 output, 18–34 VDC or 15–24 VAC FCTHG (-G)
    Rule: first decide where the measurement is made (duct, room, outdoors), then what you need from the transmitter: separate analog signals for a controller (transmitter, 3 outputs), data only to a BMS (Modbus / PoM version), or direct fan control with a single output (smart sensor). Finally – the supply and number of wires: -F – 24 VDC, 4-wire, separate grounds; -G – AC or DC, 3-wire, common ground; -M / -H – power over the Modbus cable (RJ45).
    When to choose another solution: for measurement only with 3 outputs – RSTHF-3 / RSTHG-3; for flush mounting – FCTH series; when CO2 is also needed – RCMF-3 series.

    Pros

    • Transmitter and controller in one
    • Control by T, rH or both
    • Accuracy ±0.4 °C, ±3 % rH
    • Modbus RTU, firmware updated over the network
    • 0-10 VDC / 0-20 mA / PWM output
    • LED indication and light sensor

    Cons / limitations

    • One control output – for separate T and rH signals choose a transmitter (RSTH-3 / DSTH-3)
    • IP30 – dry rooms only
    • The -F version is not suitable for 3-wire systems or AC supply

    Safety and installation notes

    • Installation and connection are to be carried out by a qualified electrician / automation specialist with the power disconnected.
    • Supply voltage – 18–34 VDC.
    • The -F version: 4-wire connection, separate supply and analog output grounds – not suitable for 3-wire systems and must never be connected to an alternating current (AC) supply.
    • 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.

    Quick selection guide

    0…+50 °C
    0–95 % rH
    0-10 VDC / 0-20 mA / PWM
    Modbus RTU
    18–34 VDC
    IP30
    Suitable when you need:
    • to control a fan or damper according to temperature and humidity in a room without a separate controller;
    • to implement demand-controlled ventilation in damp rooms;
    • to integrate the control into a BMS later via Modbus RTU.
    Check before use:
    • the input type of the controlled device (0-10 VDC, 0-20 mA or PWM);
    • the supply: 18–34 VDC;
    • whether separate T and rH signals are needed – then choose a transmitter.
    Important reminder: The RCTHF-2 generates a single control signal based on T and rH; it does not replace the power section of a fan speed controller.

    FAQ

    Is a separate controller required?
    No, the algorithm is built in, and the output connects directly to an EC fan, AC speed controller or damper.
    Can it be controlled by humidity only?
    Yes, the temperature (or humidity) parameter can be switched off via 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 is the difference between the -F and -G versions?
    -F is powered at 18–34 VDC and wired with 4 wires with separate grounds, while -G is powered at 18–34 VDC or 15–24 VAC and wired with 3 wires with a common ground.
    Is it suitable for a bathroom?
    It can be installed only in a dry area, because the enclosure is IP30 and humidity is measured up to 95 % rH without condensation.

    Smart room temperature and humidity sensor-controller | 0…50°C | 0-95%rH | 0-10VDC/0-20mA/PWM | Modbus RTU | 18-34VDC | IP30 | Sentera Controls | RCTHF-2

    Sentera RCTHF-2 – smart room temperature and humidity sensor-controller: 0…+50 °C, 0–95 % rH, 0-10 VDC / 0-20 mA / PWM control output, 18–34 VDC supply, IP30. Humidity- and temperature-based ventilation without a separate controller.

    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.

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