Products catalog

Home/Product Catalog/HVAC control solutions for heating and ventilation/HVAC automation/Sensors and detectors/Temperature and humidity sensors | environmental parameter measurement solutions
  • New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2
    New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2 1
    New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2 2
    New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2 3
    New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2 4
    New item   -40.97€Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2 5

    Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2

    Code: DSTHM-2
    Inquire about this item
    Price 73.18 € VAT incl.
    ( 60.48 € VAT excl. )
    114.15 € You save 40.97 €
    Offer is valid until 2026-12-31
    Want another price? Suggest yours!
  • Product description

    Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2

    DSTHM-2 – a Sentera Controls duct temperature and humidity transmitter measuring temperature (-30…+70 °C) and relative humidity (0–100 % rH) in the duct. Data is transmitted digitally only, via Modbus RTU, and the 24 VDC supply arrives over the same cable through the RJ45 connector (Power over Modbus, PoM). The dew point is calculated from the measurements.

    Key idea:
    One cable for both power and communication. The sensor is connected with a standard RJ45 cable to Sentera PoM devices or the Modbus network, so no separate power supply and no analog cables for each measuring point are needed – especially convenient when there are many sensors.
    Measurement
    -30…+70 °C / 0–100 % rH
    Output
    Modbus RTU (RS485)
    Power supply
    24 VDC via Modbus (PoM), RJ45
    Protection
    housing IP54, probe IP20

    Operating principle

    The transmitter is mounted on the duct, the probe is inserted into the airflow (min. 1 m/s), and it is connected with a single RJ45 cable: 24 VDC, GND and Modbus RTU (A, /B) run in the same cable (PoM).

    Integrated digital sensors measure duct air temperature and relative humidity, and the dew point is calculated; ranges are selected over Modbus RTU, and the values are provided in input registers (IR1 – temperature, IR11 – relative humidity). A controller, the BMS, a Sentera PoM device or SenteraWeb reads them, and the firmware is updated over the Modbus network.

    The result – accurate (±0.4 °C, ±3 % rH) duct air data in the BMS without analog signal conversion and without a separate power supply.

    Benefits DSTHM-2?
    Power and communication in one RJ45 cable – fewer wires, faster installation and no analog signal errors on long lines.

    Technical specifications

    Product type Duct temperature and humidity transmitter
    Manufacturer / code Sentera Controls / DSTHM-2
    Measured quantities Temperature, relative humidity; dew point is calculated
    Temperature range -30…+70 °C
    Humidity range 0–100 % rH, non-condensing
    Accuracy ±0.4 °C (-30…+70 °C); ±3 % rH (0–100 %)
    Output Digital – Modbus RTU (RS485), no analog outputs
    Modbus registers IR1 – temperature, IR11 – relative humidity
    Supply voltage 24 VDC via Modbus (PoM)
    Energy usage max. 0.36 W, nominal 0.27 W, Imax 15 mA
    Connection RJ45 socket
    Min. air velocity 1 m/s
    Protection class IP54 housing, IP20 probe tube
    Weight 0.15 kg (net)
    Compliance 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

    • Dew point – calculated from temperature and humidity.
    • Power over Modbus (PoM) – power and communication over a single RJ45 cable.
    • Modbus RTU – temperature and humidity in registers, ranges and parameters can be changed remotely.
    • Firmware update – over the Modbus RTU network.
    • Configuration – Configuration and monitoring – the free Sentera 3SModbus software (via the CNVT-USB-RS485 converter) or the Sensistant Modbus configurator.

    Where is it used?

    • Supply and extract ducts of air handling units
    • BMS systems with many measuring points
    • Humidification / dehumidification control
    • Sentera PoM and SenteraWeb solutions
    • Extraction of production and storage rooms
    • Supply air monitoring of heat recovery units downstream of the heat exchanger
    • Swimming pool extract air ducts

    On-demand operation

    For heat recovery unit manufacturers.
    A duct Modbus sensor with PoM connects directly to the unit controller with a single RJ45 cable.
    For air handling unit BMS integrators.
    Temperature, humidity and dew point are read from registers without analog inputs and converters.
    For HVAC commissioning engineers.
    The measuring range and Modbus address are set via 3SModbus, and the firmware is updated over the network.

    Practical application

    If temperature, humidity and dew point have to be monitored in the supply air duct of a heat recovery unit (air velocity ≥ 1 m/s), then the DSTHM-2 is connected with a single RJ45 cable to a PoM controller, and the values are read from IR1 and IR11.

    Application guide: how it is used in practice

    The DSTHM-2 adapts to different sites – only what reads its data changes:

    Site What is connected Result Installer's note
    Building with BMS RJ45 → Modbus RTU line with 24 VDC PoM power Temperature and humidity are monitored and archived centrally A separate Modbus address for each sensor
    Remote monitoring RJ45 → Sentera internet gateway → SenteraWeb Data log, graphs, internet alerts A Sentera internet gateway is required
    Sentera Modbus controller / speed controller RJ45 → Sentera device with Modbus and PoM Ventilation controlled according to the measured temperature or humidity Check that the device supplies PoM power

    How to choose a duct temperature and humidity transmitter

    Installation / output / power supply Recommended model
    Duct, 3 analog outputs (T / rH / T or rH), 18–34 VDC, 4 wires DSTHF-3 (duct transmitter, -F)
    Duct, 3 analog outputs, 18–34 VDC or 15–24 VAC, 3 wires DSTHG-3 (duct transmitter, -G)
    Duct, Modbus RTU only, Power over Modbus (PoM), RJ45 DSTHM-2 (duct Modbus transmitter) ← this model
    Duct, direct fan / damper control with 1 output, 18–34 VDC DCTHF-2 (smart duct sensor, -F)
    Duct, direct control with 1 output, 18–34 VDC or 15–24 VAC DCTHG-2 (smart duct sensor, -G)
    Duct, control signal via Modbus RTU, PoM, RJ45 DCTHM-2 (smart duct sensor, PoM)
    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 analog outputs – DSTHF-3 / DSTHG-3; for direct fan control – DCTH-2 series; for a room – RSTHM-2.

    Pros

    • Power and communication via a single RJ45 cable
    • Accuracy ±0.4 °C, ±3 % rH
    • Ranges are selected via Modbus RTU
    • Firmware is updated via Modbus
    • IP54 housing, wide -30…+70 °C range

    Cons / limitations

    • No analog outputs – a Modbus RTU controller or BMS is required
    • Powered only via PoM (24 VDC) – a device or power supply that provides PoM is required
    • IP20 probe, an airflow of ≥ 1 m/s is required

    Safety and installation notes

    • Installation and connection are to be carried out by a qualified electrician / automation specialist with the power disconnected.
    • Power supply – only 24 VDC via Modbus (PoM); do not connect the RJ45 connector to computer network (Ethernet) equipment.
    • Resetting the Modbus communication parameters – with a jumper on PROG pins 1 and 2 for at least 5 s.
    • Install the probe in the airflow, away from humidifier nozzles and condensate.

    Quick selection guide

    -30…+70 °C
    0–100 % rH
    Modbus RTU
    PoM 24 VDC
    RJ45
    IP54
    Suitable when you need:
    • to measure temperature and humidity in a duct and pass them to a BMS;
    • to reduce cabling – power and communication over a single cable;
    • to monitor the condition of supply or extract air;
    Check before use:
    • whether the controller / BMS supports Modbus RTU;
    • whether the Modbus line supplies 24 VDC PoM power;
    • A Modbus address plan for all sensors.
    Important reminder: The DSTHM-2 has no analog outputs – data is obtained via Modbus RTU only.

    FAQ

    Is there a 0-10 V output?
    No, the sensor has Modbus RTU only; for analog outputs choose DSTHF-3 or DSTHG-3.
    What is PoM?
    Power over Modbus – 24 VDC power is supplied over the same RJ45 cable as the Modbus RTU communication.
    Can the measuring range be changed?
    Yes, via Modbus RTU using the 3SModbus software or a BMS.
    How do I reset the Modbus settings?
    With a jumper on PROG contacts 1 and 2 for at least 5 seconds.
    Is it suitable for outdoor air in a duct?
    Yes, the range is -30…+70 °C and 0–100 % rH, provided the air is free of condensate.
    What airflow is needed?
    At least 1 m/s.

    Duct temperature and humidity transmitter | -30…70°C | 0-100%rH | Modbus RTU | PoM 24VDC | RJ45 | IP54 | Sentera Controls | DSTHM-2

    Sentera DSTHM-2 – duct temperature and humidity transmitter: -30…+70 °C, 0–100 % rH, Modbus RTU and 24 VDC supply via RJ45 (PoM), IP54. Suitable for BMS and SenteraWeb ventilation automation.

    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.

  • Subscribtion to new arrivals

    privacy policy

    Information