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testo 521-3 - Differential pressure measuring instrument (up to 2.5 hPa)

0560 5213
testo 521-1
  • Integrated temperature-compensated differential pressure sensor with accuracy of up to ± 0.5 Pa
  • Calculation of the flow velocity and the volume flow via Pitot tube (optional)
  • Direct zeroing of the display values of pressure probes
  • 2 probe inputs for additional pressure and temperature probes
     
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    The testo 521-3 differential pressure measuring instrument is designed for high-precision differential pressure measurements in air conditioning and ventilation technology. It can be used, for example, for measurements in clean rooms and for flue inspections – thanks to a high level of accuracy and outstanding resolution. In conjunction with a Pitot tube (optional), the integrated pressure sensor measures flow velocities of +1 to +20 m/s.
    The integrated temperature-compensated differential pressure sensor performs measurements to an accuracy of up to ± 0.5 Pa. In addition, you can attach up to 2 further optional probes to the measuring instrument. This means you can flexibly adapt the differential pressure measuring instrument to your application. You have the choice of the following probes:
    • Differential pressure probes
    • Absolute pressure probes
    • Relative pressure probes
    • Temperature probes (e.g. surface probes or immersion and penetration probes)

    The practical features of the testo 521-3 differential pressure measuring instrument

    The integrated differential pressure sensor enables the testo 521-3 measuring instrument to calculate flow velocity and volume flow using a Pitot tube (which can be ordered separately). The differential pressure measuring instrument also offers timed and multi-point mean calculation.
    The optional ComSoft software enables you to save the measurement data so that it is linked to the measuring location and analyze it on the PC. You can use the optional testo fast printer to print out measurement data directly at the measuring location.
    You can choose between the following units for pressure measurement: mbar, hPa, bar, Pa, kPa, inH2O, mmH2O, torr and psi. The mean value, the last measured value and the min./max. values can be displayed at the press of a button.
     

    testo 521-3 differential pressure measuring instrument, including calibration protocol and batteries.

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  • Temperature - NTC

    Measuring range
    -40 to +150 °C
    Accuracy
    ±0.2 °C (-10 to +50 °C)*
    ±0.4 °C (Remaining Range)*
    Resolution
    0.1 °C
    *Accuracy information applies only to instrument without probes connected

    Temperature - TC Type K (NiCr-Ni)

    Measuring range
    -200 to +1370 °C
    Accuracy
    ±0.4 °C (-100 to +200 °C)*
    ±1 °C (Remaining Range)*
    Resolution
    0.1 °C
    *Accuracy information applies only to instrument without probes connected

    Differential pressure (internal sensor) - Piezoresistive

    Measuring range
    0 to 2.5 hPa**
    Accuracy
    ±(0.5 Pa ±0.5 % of mv) (20.1 to 250 Pa)
    ±0.5 Pa (0 to 20 Pa)
    Resolution
    0.1 Pa
    Static pressure
    1000 hPa
    Overload
    50 hPa
    Zeroing
    to 0.5 hPa
    **Sensor is not suitable for long-term measurements
    Contact Us
    Testo Ltd
    Newman Lane
    GU34 2URAlton
    HampshireUnited Kingdom
    01420 544433

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