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Hot wire probe (digital) - including temperature and humidity sensor, wired

0635 1572
Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe with scaled telescope
Volumetric flow measurement in ventilation ducts with hot wire probe and testo 440
Volumetric flow measurement in ventilation ducts with hot wire probe and testo 440
  • Comprehensive HVAC Measurement – Simultaneous detection of air velocity, volume flow, air temperature, and humidity for efficient ventilation assessments.
  • High Precision Performance – Accurate results from 0 to +30 m/s with automatic absolute pressure compensation for reliable data in any condition.
  • Optimised for Accessibility – Scaled telescope extends up to 1.0 m (optionally to 2.0 m), enabling comfortable measurements even in large or hard-to-reach ducts.
  • Intelligent Calibration Concept - Calibration is handled via the probe itself, allowing continuous use of the measuring instrument and minimising disruption.
  • The wired digital hot wire probe offers precise, all-in-one measurement of air velocity, volume flow, temperature, and humidity in ventilation systems. With a telescopic shaft, intuitive controls, and smart calibration, it’s built for reliable HVAC assessments in demanding environments.
    The digital hot wire probe with integrated temperature and humidity sensors is the ideal solution for accurate and convenient airflow measurement in ventilation ducts. Designed for use with a compatible testo multifunction measuring instrument (sold separately), this robust wired probe measures air velocity (0 to +30 m/s), volume flow, temperature, and humidity with high precision.

    A scaled telescope extends up to 1.0 meter and is optionally extendable to 2.0 meters, allowing easy access to deep or high-up ductwork. Thanks to absolute pressure compensation, the probe ensures consistent accuracy under changing environmental conditions.

    A built-in button on the handle lets you store readings and manage measurement series directly at the measurement point, simplifying the workflow. The rotatable sensor protection cap helps preserve the sensitive hot wire sensor from damage and debris during transport or storage.

    The probe is part of a modular system featuring a universal handle – connect various probe heads to reduce gear load and increase testing flexibility. Users can switch to a Bluetooth® handle (optional) for wireless operation or extend the reach with a telescopic extension for measurements in large-scale systems.

    With Testo’s intelligent calibration concept, only the probe head requires calibration, ensuring minimal downtime and continued measuring efficiency.

    Hot wire probe including temperature and humidity sensor (consisting of hot wire probe head, handle adapter and cable handle (cable length 1.4 m)), telescope (extendable to 1.0 m) and calibration protocol.

    Temperature - NTC

    Measuring range
    -20 to +70 °C
    Accuracy
    ±0.8 °C (-20 to 0 °C)
    ±0.5 °C (0 to +70 °C)
    Resolution
    0.1 °C

    Humidity - Capacitive

    Measuring range
    5 to 95 %RH
    Accuracy
    Hysteresis: ±1.0 %RH
    long-term stability: ±1 %RH / year
    ±3 %RH (10 to 35 %RH)
    ±0.06 %RH/K (k=1)
    ±3 %RH (65 to 90 %RH)
    ±2 %RH (35 to 65 %RH)
    ±5 (Remaining Range)
    Resolution
    0.1 %RH

    Absolute Pressure

    Measuring range
    +700 to +1100 hPa
    Accuracy
    ±3.0 hPa
    Resolution
    0.1 hPa

    Accessories

    Sensor heads

  • Sensor heads
    16 mm vane probe head including temperature sensor
    16 mm vane probe head including temperature sensor; for attachment to extendable telescope for air velocity probes with universal handle – measuring range +0.6 to +50 m/s, -10 to +70 °C
      :
      0635 9570
    • Sensor heads
      High-precision 100 mm vane probe head including temperature sensor
      High-precision 100 mm vane probe head including temperature sensor: for attachment to extendable telescope for air velocity probes with universal handle or to a universal Bluetooth® or cable handle – measuring range +0.1 to +15 m/s, -20 to +70 °C
        :
        0635 9370
      • Sensor heads
        100 mm vane probe head
        100 mm vane probe head: for attachment to extendable telescope for air velocity probes with universal handle or to universal Bluetooth® or cable handle – measuring range +0.3 to +35 m/s, -20 to +70 °C
          :
          0635 9430
        • Sensor heads
          Hot wire probe head including temperature and humidity sensor
          Hot wire probe head including temperature and humidity sensor: for attachment to extendable telescope for air velocity probes with universal handle – measuring range 0 to +30 m/s, -20 to +70 °C, 5 to 95% RH
            :
            0635 1570
          • Sensor heads
            Humidity/temperature probe head
            Humidity/temperature probe head: for attachment to universal Bluetooth® or cable handle – accuracy ±2% RH / ±0.5 °C, measuring range 0 to 100% RH / -20 to +70 °C
              :
              0636 9730
            • Sensor heads
              High-precision humidity/temperature probe head: for attachment to a universal Bluetooth® or cable handle – accuracy: ±(0.6% RH + 0.7 % of m.v.) (0 to 90% RH) / ±0.3 °C (+15 to +30 °C)
                :
                0636 9770
              • Sensor heads
                CO2 probe head including temperature and humidity sensor
                CO₂ probe head including temperature and humidity sensor: for attachment to universal Bluetooth® or cable handle – measuring range 0 to 10,000 ppm, -10 to +50 °C, 5 to 95% RH
                  :
                  0632 1550
                • Sensor heads
                  CO probe head
                  CO probe head: for attachment to universal Bluetooth® or cable handle – measuring range 0 to 500 ppm
                    :
                    0632 1270
                  • Contact Us
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                    GU34 2URAlton
                    HampshireUnited Kingdom
                    01420 544433

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