KERN & SOHN TN 60-0.01EE - Manual (Page 8)

8 TN_EE-BA-e-1410
perpendicular to the material surface. In this case, it will be difficult to exactly locate
tiny irregularities in the material being measured, as the focus of the sound beam no
longer lies directly beneath the transducer.
4 Operation
4.1 Power On/Off
The instrument is turned on by pressing the key. When the gauge is turned on, it
will first perform a brief display test by illuminating all of the segments in the display.
After one second, the gauge will display the sound velocity now used, indicating the
gauge is ready for use.
The gauge can be turned off by pressing the key. The tool has a special memory
that retains all of its settings even when the power is off. The gauge also features an
auto-power down mode designed to conserve battery life. If the gauge is idle for 5
minutes, it will turn itself off.
4.2 Setting the Measurement Mode
Often time users and inspectors in the field are faced with coated materials such as
pipes and tanks. Typically inspectors will need to remove the paint or coating prior to
measuring, or allow for some fixed amount of error introduced by the paint or coating
thickness and velocity.
The error can be eliminated with this gauge by using a special echo-echo mode to
perform measurements for applications such as this. The gauge gives you this fea-
ture in a simple way, one button toggle, eliminating the need to remove the paint or
coating.
To switch between pulse-echo mode and echo-echo mode, simply press the
key.
4.3 Perform Probe Zero
Note: The Probe Zero operation is only to be applied in Pulse-Echo mode, not
in Echo-Echo mode.
The key is used to “zero” the instrument in much the same way that a mechanical
micrometer is zeroed. If the gauge is not zeroed correctly, all the measurements that
the gauge makes may be in error by some fixed value. When the instrument is “ze-
roed”, this fixed error value is measured and automatically corrected for all subse-
quent measurements. The instrument may be “zeroed” by performing the following
procedure:
1) Plug the transducer into the instrument. Make sure that the connectors are fully
engaged. Check that the bearing face of the transducer is clean and free of any
debris.
2) Press the key to activate the zero mode.