Keithley 2002, Руководство по началу работы

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Two and four-wire resistance measurements
Assuming “BENCH” reset conditions, the basic procedure is as follows:
1. Connect test leads to the Model 2002 as follows:
A. For 2-wire, connect the test leads to INPUT HI and LO.
B. For 4-wire, connect the test leads to INPUT HI and LO, and SENSE
Ω
4 WIRE HI
and LO. Recommended Kelvin test probes include the Keithley Models 5805 and
5806.
Either the front or rear inputs can be used; place the INPUTS button in the appropriate
position.
2. Select the measurement function by pressing
Ω
2 or
Ω
4.
3. The AUTO annunciator indicates that autoranging is enabled. If you want manual rang-
ing, use the RANGE
▲
and
▼
keys to select a measurement range consistent with the
expected resistance.
4. Connect test leads to the resistance as shown in Figure 6.
CAUTION Do not apply more than 1100V peak between INPUT HI and LO, or instru-
ment damage may occur.
5. Observe the display. If the “Over o w” message is displayed, select a higher range until
a normal reading is displayed. Use the lowest possible range for the best resolution.
6. Take a reading from the display.
Shielding
It helps to shield resistances greater than 100k
Ω
to achieve a stable reading. Place the resis-
tance in a shielded enclosure and electrically connect the shield to the INPUT LO terminal of
the instrument.
1-12 Front Panel Operation