Elcometer NDT MTG6 Guia Del Usuario página 19

8 CALIBRATING YOUR GAUGE (continued)
8.6 USING FACTORY CALIBRATION
Press Menu/Calibration/Factory Calibration to restore the default
factory calibration setting of the standard sound-velocity for steel,
5920m/s (approximately 0.233in/µs).
8.7 TEST CALIBRATION
This feature allows the user to test the calibration by taking a reading
on an uncoated sample of material of known thickness, without the
reading being saved.
To test the calibration:
1 Press Menu/Calibration/Test
Calibration.
2 When prompted, apply couplant to
the uncoated sample.
3 Press the transducer on to the
uncoated sample, making sure it is
flat against the surface.
The display will show a thickness value which is constantly updating. 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.
4 Remove the transducer from the uncoated sample. The last
reading is held on screen. If not representative, repeat
Steps 2-3.
Excessive use of couplant can result in a distorted reading when the

transducer is removed from the surface.
5 Press 'Validate' to retain the existing calibration but refresh the
associated time and date of calibration to the current time and
date, 'Cal' to re-calibrate the gauge or 'Ok' to exit the test
calibration procedure.
8.8 CALIBRATION CHECK
When enabled, this feature warns the user
as readings are taken, of any which are
outside the values at which the gauge was
initially calibrated.
When a reading is 10% or more below the
lower calibration value or exceeds 10%
above the higher calibration value, the
alarm sounds, the red LED flashes and the
calibration icon turns red.
www.elcometer.com
R
en-18