Statistics - Elcometer 204 User Manual

6 TAKING A READING (continued)
6.2 TAKING A READING
1 Apply a small amount of couplant to the test surface.
2 Press the transducer into the couplant, making sure it is flat
against the surface.
Moderate pressure on the top of the transducer using the thumb or index

finger is sufficient; it is only necessary to keep the transducer stationary
and seated flat against the surface of the material.
3 The display will show a value which is constantly updating. The
gauge will take 4 readings per second when the transducer is in
contact with the surface of the material.
The stability of the reading is indicated on the stability bar to the right of

the display. A valid reading has a stability of 5 or more. If the stability
indicator has fewer than 5 bars showing or the numbers on the display
seem erratic, make sure there is an adequate film of couplant beneath the
transducer, and that the transducer is seated flat against the material. If
the condition persists, it may be necessary to select a different transducer
(size or frequency) for the material being measured.
4 Press 'Save' to include the current reading in the statistics
calculations. The last reading is held on screen when the
transducer is removed from the surface.
The last saved reading can be deleted and removed from the statistics

calculations by pressing Menu/Delete Last Reading.

7 STATISTICS

The Elcometer 204 calculates and displays the following statistical
values:
Number of Readings (n:)

Mean ( :)

X
Lowest Reading (Lo:)

Highest Reading (Hi:)

Standard Deviation (σ:)

Coefficient of Variation (cv%:)

To display the statistics, press Display/Setup Display/Top Display (or
Bottom Display as required).
To clear the current statistical values, press Display/Clear Statistics.
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