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testo 521-1 - Differential pressure measuring instrument 0 to 100 hPa (accuracy ±0.2% of f.v.)

testo 521-1
testo 521-1
The high precision testo 521-1 differential pressure measuring instrument is ideal for accurate differential pressure measurements in air conditioning and ventilation technology, for pressure drop on filters, for instance, for checking fans and extractors, or for pitot tube measurements.
  • Integrated differential pressure sensor with an accuracy of 0.2 % of f.v.
  • Calculation of the flow velocity and the volume flow via Pitot tube (optional)
  • Multi-point and timed mean calculation
  • 2 probe inputs for additional pressure and temperature probes

The highly accurate differential pressure meter, testo 521, with an internal pressure sensor from 0 to 100 hPa, is ideal for pitot tube measurements in the range of 5 to 100 m/s. The testo 521 is available in 2 accuracy classes, the testo 521-1 with an internal pressure sensor with Class 0.2, and the testo 521-2 with an internal pressure sensor with Class 0.1.


In the case of velocity speeds in the range of 1 to 12 m/s, you can carry out accurate measurements using the 100 Pa probe, which can be attached externally.


The measurement data can be saved according to location, and analyzed on your PC, or printed on site on your testo printer.

Temperature - NTC

Measuring range
-40° to 302 °F / -40 to +150 °C
Accuracy
±0.7 °F (Remaining Range)* / ±0.4 °C (Remaining Range)*
±0.4 °F (14° to 122 °F)* / ±0.2 °C (-10 to +50 °C)*
Resolution
0.1 °F / 0.1 °C
*Accuracy information applies only to instrument without probes connected

Temperature - Type K TC

Measuring range
-328° to 2498 °F / -200 to +1370 °C
Accuracy
±0.7 °F (-148° to 392 °F)* / ±0.4 °C (-100 to +200 °C)*
±2 °F Remaining Range* / ±1 °C Remaining Range*
Resolution
0.1 °F / 0.1 °C
*Accuracy information applies only to instrument without probes connected

Differential pressure (internal sensor) - Piezoresistive

Measuring range
0 to 40 InHâ‚‚O / 0 to 100 hPa
Accuracy
±0.2 % of full-scale value
Resolution
0.01 InHâ‚‚O / 0.01 hPa
Static pressure
400 InHâ‚‚O (abs) / 1000 hPa (abs)
Overload
120 InHâ‚‚O / 300 hPa
Zeroing
to 1.0 InHâ‚‚O / to 2.5 hPa
testo 521-1 differential pressure measuring instrument, including calibration protocol and batteries

Differential pressure probes

Pitot Tubes

Pitot tubes

Pressure Probe

Probes

Relative pressure probe

Headquarters
Testo Inc.
40 White Lake Road
07871Sparta
New Jersey
800-227-0729

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