User's Manual

6 Using the product
20
6.4. Measuring
6.4.1. Volume flow measurement
✓ The volume flow hood is fitted.
1. Switch on the instrument.
2. In the instrument settings, set the application volume flow hood
and also the required measurement program:
Single measurement or Continuous measurement.
3. Press ►, ■ on the testo 420, or the trigger on the measurement
base to hold or start and stop the measurement.
4. Press to save the measurement data. Unsaved
measurement data is lost once you carry out the next
measurement.
- The target folder and file name are displayed, confirm with
to save the measurement data under this name and in the
selected folder.
6.4.2. Pitot tube measurement
1. Remove the testo 420 from the measurement base.
2. Connect the hoses to the testo 420 and to the Pitot tube.
3. Press -> Application -> Pitot tube and there set the duct
geometry, the Pitot tube factor and the temperature, and
choose between actual and standard.
4. Select the required measurement program.
5. Carry out the measurement.
6. Press to save the measurement data. Unsaved
measurement data is lost once you carry out the next
measurement.
- The target folder and file name are displayed, confirm with
to save the measurement data under this name and in the
selected folder.
6.4.3. Differential pressure measurement
1. Remove the testo 420 from the measurement base.
2. Connect the hoses to the testo 420 at + and -.
3. Press -> Application -> Pressure only.