Tonghui Electronics TH2826/A, Руководство по эксплуатации

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TH2826 Operation manual Ver1.0
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m) Connect the shorting bar (TH26010) to the test fixture.
n) Press the softkey MEAS SHORT to perform short correction.
5.3The right connection between the test fixture and the DUT
Generally, any mutual inductance, interference of the test signals, or unwanted residual factors
in the connection method incidental to ordinary termination methods will have a significant effect on
measurement, especially at high frequency. The TH2826 employs a four-terminal pair measurement
configuration that permits easy, stable, and accurate measurement while avoiding the negative
influences inherent in the above factors. These are the UNKNOWN Terminals used to connect a
four-terminal pair test fixture or test leads for measuring the device under test.
HD: High current drive
HS: High potential sense
LS: Low potential sense
LD: Low current drive
The every test terminal has its own shielding layer.
HD, HS, LD. LS must be connected to the corresponding lead wire of the DUT to make
up of the four terminal test.
If you do the test with high accuracy, to use the test fixture is recommended.
No matter you use the test fixture provided by Tonghui Company, Kelvin test leads or the
test fixture made by yourself, the following requirement must be met:
1) The distributed resistance must be decreased to the minimum, especially when the high
resistance DUT is tested.
2) The contact resistance must be decreased to the minimum.
3) Short correction and open correction can be performed between the two contact points.
Note: 1) When the DUT has the polarity, the high potential terminal should be connected to
“+” or HD, HS terminal, the low potential terminal should be connected to “-”or LD,
LS terminal on the front panel.
2) Do the discharge before the DUT is tested to avoid the damage to the instrument.
5.4Eliminate the disturbance of the stray capacitance