Hioki DSM-8104, Instruction Manual

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6. Measurement
Works for insulation resistance are diverse in materials, shapes, electrical characteristics
and other parameters. Insulation resistance is measured by various methods suiting
these parameters.
This chapter describes the measuring terminals of the meter and measuring methods for
insulation resistance that are suitable to various works.
6.1
Functions of and Connecting Measuring Terminals
6.1.1 Functions of measuring terminals
The functions of the measuring terminals located on the front panel are described.
“INPUT”:
A coaxial measuring input terminal whose outer electrode (shielded side) is
connected to the “GUARD” terminal.
“GUARD”:
A guard terminal and is on the common side of the current measuring unit.
The terminal is used for guarding to eliminate impacts of a leakage current
that passes through the holder and jig of a sample. The electrical polarity
of the “GUARD” terminal is “-.”
“GROUND”: A grounding terminal for reducing impacts of noise and hazard of an
electrical shock.Normally connected to the “OUTPUT” terminal or
“GUARD” terminal by a short bar.
“OUTPUT”: A measuring voltage output terminal. Insulation resistance is measured
between this “OUTPUT” terminal and the “INPUT” terminal.
The electrical polarity of the “OUTPUT” terminal is “+.”
“CHARGE”: A charging voltage output terminal that is used when precharging a sample
before measurement.
The precharge voltage is output between the “OUTPUT” and “CHARGE”
terminals. The precharge voltage is the same level as that of measuring
voltage. The potential of the “CHARGE” terminal is the same as that of the
“GUARD” terminal and the polarity of it is “-.”
[Warning]
Setting of measuring voltage outputs voltage of maximum 1000V between the
“OUTPUT” terminal and “INPUT” terminal or “GUARD” terminal. It is very
hazardous. Be certain to connect a measuring terminal by turning the
POWER switch off and checking that “POWER” on the panel is extinguished.
Caution. High voltage is output also between the “OUTPUT” terminal and
ground if the “GUARD” terminal and “GROUND” terminal are connected.