select option
“
Correct >0<" and press button
. After setting to correction menu select
option “Correct”, close the ends of the measuring cables (short the probes) and press button
. The instrument measures resistances of the measuring cables, saves the result in the
memory and enables the zero-point correction mode. After that the display shows “
>0<
”
,
and
the difference between the measured resistance and that of the measuring cables is shown
as a result. It is recommended to perform zero-point correction procedure from time to time,
as well as in case of measuring cables replacement.
Figure 2.9 –
Correction of measuring cables resistance
To disable zero-point correction mode enter the correction menu, select option
“Disable” and press button
.
Note. If the resistance of the measurement object is much lower than that of the
measuring
cables, results with a negative sign can be displayed because of measurement
errors with enabled zero-point correction.
2.3.8 Measurement of varistor voltage, discharge arresters breakdown voltage
The modes are intended to check the compliance of overvoltage limiters with the
certificate specifications:
- varistor voltage is a voltage value at non-linear overvoltage limiter (varistor) at
passing of 1 mA direct current through it;
- static breakdown voltage of the discharge arrester is a voltage value, at which arc
ignition of the discharge occurs due to slow voltage increase.
Connect cables according to Figure 2.10.
Attention! During measurements, high voltage is generated at sockets and cables.
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