Coulombs Calibration - Keithley 6512 Instruction Manual

Proceed as follows:
1. Connect the Model 263 Calibrator/Source to the Model
6512, as shown in Figure 7-3.
2. Place the Model 6512 in the amps function, and select
the 200pA range.
3. On the Model 6512, enable zero check and zero correct
in that order.
4. Program the Model 263 to output 00.000pA, and release
zero check on the Model 6512.
5. After allowing the reading to settle for a few seconds,
press SUPPRESS to zero the display of the Model 6512.
6. Program the Model 263 to output 190.000pA.
7. Adjust the display of the Model 6512 to read 190.00pA
using the Model 6512 ADJUST buttons.
8. Program the Model 263 to output 00.000pA by pressing
ZERO on the Model 263.
9. On the Model 6512, disable zero correct and suppress.
10. Using Table 7-3 as a guide, select the next electrometer
range and calibrator range, and repeat the basic proce-
dure in steps 3 through 9. Calibrate all the electrometer
ranges listed in the table.
Table 7-3
Model 6512 amps calibration summary
6512 & 263 263 output
range current
200pA 190.000pA
20nA 19.0000nA
20µA 19.000µA
20mA 19.000mA
NOTE: Use AMPS (active) mode of Model 263 to source current.
Figure 7-3
Connections for Model 6512 calibration
6512 reading
190.00pA
19.000nA
19.000µA
19.000mA
COMMON
2-SL0T
OUTPUT
TRIAX
CABLE
MODEL 263
BANANA CABLE

7.4.11 Coulombs calibration

Use the following procedure to calibrate the 20nC range.
Once this range is calibrated, the two remaining ranges are
automatically calibrated.
1. Connect the Model 263 Calibrator/Source to the Model
6512, as shown in Figure 7-3.
2. Place the Model 6512 in the coulombs function, and se-
lect the 20nC range.
3. While in standby, program the Model 263 to source
19.0000nC.
4. On the Model 6512, enable zero check and then zero
correct. Disable zero check, and enable suppress to null
the effects of zero check hop.
5. Press the OPERATE button on the Model 263. The cal-
ibrator will source for one second.
6. Adjust the display of the Model 6512 for a reading of
19.000nC using the ADJUST buttons of the Model 6512.
7. Repeat steps 4 through 6 until the reading on the Model
6512 reads 19.000nC after OPERATE is pressed on the
Model 263 calibrator.
8. Enable the Model 6512 zero check mode.
6171 3-SLOT MALE TO
2-LUG FEMALE TRIAX ADAPTER
INPUT
MODEL 6512
Maintenance
COM
7-5