Calibration
2-10
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 al-
low 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 accu-
racy.
2. Send the following command over the bus:
:CAL:PROT:DC:ZERO
3. Wait until the Model 2001 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.)
Step 3: +2V DC calibration
1. Disconnect the low-thermal short, and connect the DC
calibrator to the INPUT jacks, as shown in Figure 2-2.
Table 2-5
IEEE-488 bus comprehensive calibration summary
Step
Description
IEEE-488 bus command
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Warm-up, unlock calibration
DC zero calibration
+2VDC calibration
+20VDC calibration
20k¾ calibration
1M¾ calibration
Open-circuit calibration
Calculate constants
Check for errors
Perform user AC cal
Check for errors
Save calibration dates
Save calibration constants
Lock out calibration
:CAL:PROT:DC:ZERO
:CAL:PROT:DC:LOW <value>
:CAL:PROT:DC:HIGH <value>
:CAL:PROT:DC:LOHM <value>
:CAL:PROT:DC:HOHM <value>
:CAL:PROT:DC:OPEN
:CAL:PROT:DC:CALC
:SYST:ERR?
:CAL:UNPR:ACC
:SYST:ERR?
:CAL:PROT:DATE “<cal_date>”
:CAL:PROT:NDUE “<due_date>”
:CAL:PROT:DC:SAVE
:CAL:PROT:LOCK
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 ex-
ternal sensing is to be turned on.
2. Set the DC calibrator output to +2.00000V, and turn ex-
ternal sense off.
3. Send the following command to the Model 2001 over
the IEEE-488 bus:
:CAL:PROT:DC:LOW 2.0
(Be sure to use the exact calibration value if you are us-
ing a voltage other than 2V. The allowable range from is
0.98V to 2.1V).
NOTE
For best results, use the calibration values
given in this procedure whenever possible.
4. Wait until the Model 2001 finishes this step before going
on.