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testo 420 - Differential pressure measuring instrument

0560 0420
  • Differential pressure measurement, e.g. to check filters in air conditioning and ventilation systems
  • Calculate flow velocity and volume flow using a Pitot tube
  • Handy instrument featuring a large display and user-friendly menu guidance
  • Save measurement data for analysis and documentation
  • Use the testo 420 differential pressure measuring instrument to carry out simple, efficient tests on filters. You can also use the measuring instrument in conjunction with a Pitot tube to measure flow velocity and volume flow really easily in ventilation ducts.
    The testo 420 differential pressure measuring instrument is suitable for accurate differential pressure measurement up to 120 Pa, e.g. when checking filters in HVAC systems. Flow velocity and volume flow are calculated by the testo 420. The measuring instrument can also be used for absolute pressure measurement.

    Differential pressure measuring instrument with practical functions

    You can use a Pitot tube and compatible connection hoses (both optional) to measure the flow velocity and volume flow in ventilation ducts. Timed and multi-point mean calculation, as well as the combination of the two, along with simple input of the duct geometry provide you with support for measurements in ducts.

    The automatic zeroing ensures higher accuracy for low pressures. All measuring values are easy to read on the large display which has an illumination function.

    Documenting the measurement data

    Measurement data can be stored in the differential pressure measuring instrument for analyses and documentation. It's easy to manage the measurement data on the PC without any additional software, via the plug & play function.

    testo 420 differential pressure measuring instrument including batteries and calibration protocol.

    Differential Pressure - Piezoresistive

    Measuring range
    +0.1 to +14 m/s
    -120 to +120 Pa
    ±2 % of mv + 0.5 Pa at +22 °C, 1013 hPa
    0.01 m/s
    0.001 Pa
    Reaction time
    1 s (t₉₀)

    Absolute Pressure

    Measuring range
    700 to 1100 hPa
    ±3 hPa
    0.1 hPa
    Reaction time
    1 s

    General technical data

    150 x 85 x 35 mm
    Operating temperature
    -5 to +50 °C
    EU-guideline 2014/30/EU
    Battery type
    Alkali manganese, mignon, type AA
    Battery life
    40 h
    Display size
    Display function
    Dot matrix
    Display ligthing
    with illumination
    2 GB (internal)
    Storage temperature
    -20 to +60 °C