Automatic Zero - Extech Instruments TKG250 User Manual

Extech Instruments

Automatic Zero

To perform an Automatic Zero or Auto Zero, you must first select a transducer option
from the Xducer selection screen and press the OK key.
To continue the Auto Zero, follow these steps:
1. Follow the instructions given on each display screen; the first of which will
prompt you to wipe off any couplant from the transducer and wait three seconds.
The waiting time is shown in the changing pie-clock graphic on the display
screen.
2. After three seconds the gauge automatically begins to zero the transducer. During
the delay line calibration a screen appears displaying the message "Performing
Auto Zero".
3. A warning message will appear on the display screen if the delay line is below the
acceptable limit for accurate thickness measurements. You will need to replace
the transducer or select the F1 key to acknowledge the warning message and
continue using the same transducer, which may have a worn surface.
4. After three seconds or after acknowledging the warning message, the display
shows the instrument parameters for 3 seconds before going to Measurement
mode.
18 TKG250- EN V2.4 11/13