Hioki DSM-8104, Инструкция по эксплуатации

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Detection is made by detecting the electrostatic capacity and this function cannot be
used with samples whose electrostatic capacity component is small such as pure
resistance.
The cable length is predetermined because an electrostatic capacity of the measuring
cable enters the jig capacity in parallel. The measuring cable length was adjusted to 1m
during a preshipment inspection at the factory. Readjustment will be necessary if a
longer cable is required. However, the maximum cable length guaranteed for detection
accuracy is 2m. The cable length can be lengthened up to about 4m if the electrostatic
capacity of a sample is several thousand pF or higher. Nevertheless, the jig capacity
offset capacity will deteriorate and errors of more than 50% will result. (Errors are
±20% or less if the cable length is 1m)
Contact checks are made in an auto execute mode, in which checks are made for each
measurement, and in a single execute mode in which checks are made by keying the
panel keys or by interface commands when needed.
(1) Setting auto contact check execute
Press [SHIFT] [F4] C.CK on the setting screen referring to 4.5 “Display Screen”
and
5.1.1 “Screen types.” Select on the screen whether to (execute · not execute)
contact check during measurement.
Selection made for contact checks will be indicated by a side mark.
The side mark will flash in case the result of a voltage check is not acceptable.
[Notice]
Measurement and data output will be made as normal even if a decision of
contact check is <NG>. However, signals will not be saved in the data
buffer if the result of a contact check is <NG>.
[Notice]
Be certain to set an open correction value when using the contact check
function. Otherwise errors will result. A side mark (“
◄ ”) will be lit in the
“OPEN SET” window in the lower left of the front panel when open correction
is executed once.
[Warning]
In open correction, measuring voltage is momentarily output to the
measuring terminal. Carefully check that no hand or other body part is
contacting the jig or measuring circuit before pressing the [OPEN] key.
Maximum 1000V voltage is output and an electric shock is a hazardous
possibility.
(2) Open correction value setting
Set a decision capacity in contact check when setting an open correction value.
Press the [OPEN] (SET OPEN CHECK PARAMETER) key on the measurement
screen. The screen will change to the screen to set a reference value for
contact check. (See Fig. 6.12)