Measurement Of The Depth Of Cavities And Roughness - NOVOTEST TP-2020 Operating Manual

To completely remove the average value and start the new measurement series, press «
select «DEL ALL». Now, you can start the new measurement cycle with the average value.
To exit the measurement mode with averaging, set «CURRENT» in the «SETTINGS» section.

2.3.12 Measurement of the depth of cavities and roughness

The DSH probe works by the principle of a profile gauge. The measurement value displayed is the
distance between the measurement needle and the basic surface of the probe.
By setting the probe needle into cavities, pits, etc. their depth can be measured.
By making at least ten measurements along the line on the surface in the averaging mode (c. 2.3.11),
user can evaluate the roughness of this surface by Rz parameter.
To match the readings of the device with the actual ones when evaluating the surface roughness or
measuring the depth of the grooves, calibrate the probe on a polished base. The surface roughness must
be Ra 0.32 µm. The probe calibration provides for the zero setting, (c. 2.3.3).
To make measurement, do the following step:
1. Connect the DSH probe to the device (2.2.3).
2. Turn the device on (2.3.1).
3. Set the base material in the device settings – «Non-ferromagnetic base», and set the coating
material to «Dielectric coating».
4. Set zero on the polished base (Ra≤0.32 µm), under c. 2.3.3.
Measurement of the depth of cavity:
5. Set the probe on the prepared block or part upright and push it down without wiggling.
When the device makes a measurement, the sound signal will be generated, and the display will
show the measurement result (fig. 2.28).
Figure 2.28 – The graphic display after measurement with DSH probe
6. To start a new measurement, lift the probe into the air, and another single signal will sound,
then the device is ready for a new measurement. The indicator shows the last measurement
result which changes only during the next measurement.
7. To turn the device off, press and hold «
Evaluation of roughness:
1. Enter the mode with averaging (c. 2.3.10).
2. Set the probe on the prepared block or part upright and push it down without wiggling.
3. When the device makes measurement, the signal will sound, and the display will show the
measurement result.
4. To start the new measurement, put the probe into the air. The display will show the latest
measurement result, changing only with the next measurement.
5. Make at least ten measurements along the line on the surface, and the averaged value will
indicate the roughness Rz.
RDC.OD.TP-2020.000 OM
Coating Thickness Gauge NOVOTEST TP-2020
Figure 2.27 – Menu of selection of actions
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Operation manual
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