TeraOhm 5kV
10
4. Performing measurements
4. 1. Switching on the instrument
Autocalibration
The instrument is switched ON by pressing the
ON/OFF
key. After turning on
,
the
instrument first executes the autocalibration (Fig. 5).
It is necessary that the measuring test leads are disconnected during autocalibration. If
not the instrument will require disconnection of the test leads and repeat switching OFF
and ON.
After finishing the autocalibration
,
the instrument is prepared for normal operation.
Autocalibration prevents lowering of the accuracy when measuring very low currents. It
compensates the effects caused by ageing, temperature and humidity changes etc.
A new autocalibration is recommended when the temperature changes by more than
5
°
C.
Fig. 4.
First introduction
Fig. 5.
Auto-calibration state
Note:
If the instrument detects incorrect state during the autocalibration, the following warning
message will be displayed:
ERROR!
-TEST LEADS CONNECTED:
DISCONNECT AND SWITCH ON THE INSTRUMENT AGAIN
- CONDITIONS OUT OF RANGE: PRESS START TO CONTINUE
Possible reasons for out of range conditions are excessive humidity, too high
temperature, etc. In this case it is possible to perform measurements but results could
be out of technical specification.
Backlight operation
After turning the power on the LCD backlight is automatically turned on. It can be turned
OFF and ON by simply clicking the
LIGHT
key.
Backlight turns off automatically approximately 10s after switching it ON
,
if the
instrument is supplied by the internal battery.
