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    testo 425 - Air Velocity Meter with thermal flow probe

    0560 4251
  1. Temperature and flow measurement as well as volumetric flow calculation
  2. Permanently attached extendible telescopic probe
  3. With single and multi-point averaging
  4. Hold function, display of min/max value, Auto-off function
    5. The functional testing of ventilation and air conditioning systems includes monitoring the flow speed in ventilation ducts. If the air flow velocity and volumetric flow are not set correctly, the room air quality may suffer. The testo 425 air velocity meter measures the air velocity and automatically calculates the volumetric air flow.

    In order to establish whether an air conditioning or ventilation system is functioning properly, among other things you need to check the flow speed or the volumetric flow in the ventilation duct. If the air flow velocity is too low, the room loads are not correctly discharged and optimum room air quality can no longer be guaranteed.

    testo 425 air velocity meter for quick, easy flow measurement

    The testo 425 air velocity meter enables quick spot measurements in ventilation ducts. It records the flow speed, calculates the volumetric flow and also measures the temperature. With a measuring range of 0 to +20 m/s, this air velocity meter is particularly well suited to low air flow velocity.

    The air velocity meter features a telescopic flow probe. The telescope can be extended to a length of up to 820 mm and has a probe head diameter of 7.5 mm.

    Like the flow speed, would you also like to detect the volumetric flow on your air conditioning or ventilation system? This is no problem for the testo 425 air velocity meter. When you input the duct surface area, it automatically calculates the volumetric flow during the flow measurement. Single and multi-point averaging provides an indicator of the average volumetric flow, flow speed and temperature reading.

    You can read off the current readings and the min/max and calculated mean value at any time on the illuminated display. Using the Hold button, you can freeze the current reading in order to compare it with another value, for example. If you should ever forget to switch off the air velocity meter, the Auto-off function will take care of this for you. This conserves your batteries and ensures that your air velocity meter is ready for use in the next measurement.

    Equip yourself with accessories for the air velocity meter

    To make sure that you are well-prepared for any circumstances, we recommend that when purchasing the air velocity meter, you also order our practical accessories: as an added option we offer a handy pocket, a transport case and also the TopSafe protective cover (to protect the air velocity meter from water, dirt and impacts).

    testo 425 air velocity meter with permanently attached thermal flow probe including temperature measurement and telescope (max. 820 mm), calibration protocol and battery.

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    13. Temperature - NTC

    Measuring range
    -20 to +70 °C
    Accuracy
    ±0.7 °C (Remaining Range)
    ±0.5 °C (0 to +60 °C)
    Resolution
    0.1 °C

    Velocity -Thermal anemometer

    Measuring range
    0 to +20 m/s
    Accuracy
    ±(0.03 m/s + 5 % of mv)
    Resolution
    0.01 m/s

    General technical data

    Weight
    285 g
    Dimensions
    182 x 64 x 40 mm
    Operating temperature
    -20 to +50 °C
    Product-/housing material
    ABS
    Battery type
    9V block battery, 6F22
    Battery life
    20 h
    Storage temperature
    -40 to +70 °C