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becomes a significant parameter for the measuring conditions. In
most cases, the value of 1 minute after voltage charging is read as
a 1 minute rate value. The integrated timer can determine the
value at 1 minute after voltage charging. For details, see 6.6.
Note 3: When a measuring jig is used, it is recommended to provide an
interlocking switch with it for safety. For the interlocking, utilize
the HV-EN (high voltage enable) socket on the rear of the unit.
This makes it possible to disarm the jig when the cover of the jig is
opened. For details, see 6.4.
6.2 Discharge Function
This function is intended to discharge the change on the sample connected
to the Rx /+ measuring terminals. Discharging is automatically performed
each time the super megohmmeter is turned on, and the measurement
is ended. The sample after measurement must be disconnected from the
terminals after the discharging function is performed.
Status of the MEASURE/DISCHARGE switch can be known by the
indicator.
Indicator
ON ------ MEASURE
OFF ------ DISCHARGE
In the DISCHARGE status, a resistor of approx. 100 kΩ is internally
inserted to discharge the charge of the sample.
A time required to discharge the charge of the sample depends on the
capacitance of the sample. When the capacitance of the sample is 1μ F, it
takes approx. 1 seconds to reduce the residual voltage down to 5% of the
charged value.
Note: The discharge function does not work if the POWER switch is kept
OFF.
6.3 Charge Function
To measure a capacitive sample, charge it with the measuring voltage by
pressing the CHARGE switch. Then, the charge of the sample is completed
within several seconds.
There is no rule to determine the charging time, it is necessary to set it to
a fixed time to make the measuring conditions unchanged among samples.
WARNING
When the super megohmmeter is in the charge status do not touch
the Rx /+ measuring terminals and the sample being charged.
The measuring voltage selected with the VOLTAGE switch is directly
applied to these parts because there is a fear of electrical shock.
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