Hioki SM-8216, Инструкция по эксплуатации, Страница: 32 / 44

20
CAUTION
Before turning on the unit, be sure to set the MEASURE/CHARGE/
DISCHARGE function selector to the DISCHARGE position. If the
function selector is set to the CHARGE or MEASURE position,
a high voltage may be generated across the Rx ‘
‑
‘/’
+
’ measuring
terminals, making them live and dangerous.
(4) After completion of the measurement, set the function selector to the
DISCHARGE position to discharge and disarm the sample.
Notes:
1) Use utmost care to read the indicated value on the meter because the
the indicating meter of the instrument has a multi-scale. The full
scale values are shown at the left most of the scales.
2) In insulation resistance measurement, it takes time for the measured
value to stabilize due to the effect of static capacitance and dielectric
absorption phenomena. To secure the reproducibility of the measured
value, it is widely employed to set the measuring voltage charging
timeconstant. Most widely used measuring voltage charging times are
1-minute rating and 3-minute rating.
6.2 Usage of the MEASURE/CHARGE/DISCHARGE Function Selector
The MEASSURE/CHARGE/DISCHARGE function selector selects one of
three different functions as shown below.
1) DISCHARGE Function – lower position
This function is intended to discharge the change on the sample
connected to the Rx ‘
‑
‘/’
+
’ measuring terminals by inserting an internal
resistance of approx. 100 k
Ω
across the terminals. Discharging is
performed with most samples within a period of several seconds which is
determined by the time constant composed of a static capacitance of the
sample to be measured and the resistance of 100 k
Ω
to be inserted across the
terminals. When no measurement, keep the selector set at the DISCHARGE
position.
Note: The DISCHARGE function is operative only when the instrument is
being powered.
When the unit is turned off, the charge of sample connected to the
Rx ‘
‑
‘/’
+
’ measuring terminals cannot be discharged by setting the
function selector to the DISCHARGE position.