Keithley 2002, Руководство по калибровке

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Calibration
2-21
Step 2: DC zero calibration
1. Connect the Model 8610 low-thermal short to the instru-
ment INPUT and SENSE terminals, as shown in Figure
2-1. Wait at least three minutes before proceeding to
allow for thermal equilibrium.
NOTE
Be sure to properly connect HI, LO, and
SENSE terminals. Keep drafts away from
low-thermal connections to avoid thermal
drift, which could affect calibration
accuracy.
2. Send the following command over the bus:
:CAL:PROT:DC:ZERO
3. Wait until the Model 2002 finishes this calibration step
before proceeding. (You can use the *OPC or *OPC?
commands to determine when calibration steps end, as
discussed in paragraph 3.6 in Section 3.)
Step 3: DC volts calibration
1. Disconnect the low-thermal short, and connect the DC
calibrator to the INPUT jacks, as shown in Figure 2-2.
NOTE
Although 4-wire connections are shown,
the sense leads are connected and discon-
nected at various points in the procedure
by turning calibrator external sense on or
off as appropriate. If your calibrator does
not have provisions for turning external
sense on and off, disconnect the sense
leads when external sensing is to be turned
off, and connect the sense leads when
external sensing is to be turned on.
2. Set the DC calibrator output to +2.00000V, and turn
external sense off.
3. Send the following command to the Model 2002 over
the IEEE-488 bus:
:CAL:PROT:DC:V2 2
(Be sure to use the exact calibration value as the command
parameter if you are using a voltage other than 2V. The
allowable range from is 0.95V to 2.05V).
NOTE
For best results, use the calibration values
given in this procedure whenever possible.
4. Wait until the Model 2002 finishes this step before going
on.
NOTE
You can check for errors after each cali-
bration step by sending the :SYST:ERR?
query to the instrument. See paragraph
2.7.2.
5. Set the DC calibrator output to +20.00000V.
6. Send the following command to the instrument:
:CAL:PROT:DC:V20 20
(Send the actual calibration value in the range of 9.5V to
20.5V if you are using a different voltage.)
7. Wait until the Model 2002 finishes this step before going
on.
Step 4: Ohms calibration
1. Set the calibrator output to 1M
Ω
, and turn external sense
on.
2. Send the following command to the Model 2002:
:CAL:PROT:DC:OHM1M <value>
Here, <value> is the actual calibrator resistance value. For
example, if the calibrator resistance is 1.002M
Ω
, the com-
mand would appear as follows:
:CAL:PROT:DC:OHM1M 1.002E6
(The allowable range for this parameter is from 475E3 to
1.025E6.)
3. Wait until the Model 2002 finishes 1M
Ω
calibration
before continuing.
4. Set the calibrator resistance to 100k
Ω
.
NOTE
External sense (4-wire ohms) should be
used when calibrating all resistance rang-
es.
5. Repeat steps 2 and 3 for each of the remaining ohms cal-
ibration points shown in Table 2-9.