Keithley 6514, Instruction Manual

Page: 253 / 334

Performance Verification 18-19
7. Verify charge measurement accuracy for each of the values listed in Table 18-7. For each
test point:
• Select the correct Model 6514 measurement range.
• Make connections to the correct standard capacitor.
• Calculate the required voltage from the desired charge and actual standard capaci-
tance value: V = Q/C.
• Disable zero check.
• Set the calibrator voltage to the calculated value.
• Verify that Model 6514 charge reading is within the required limits.
• Enable zero check to discharge the capacitor.
Table 18-7
Coulombs measurement accuracy reading limits
Model
6514 range
Nominal
calibrator
voltage
Standard
capacitor
1
Applied charge
Actual
voltage
2
Model 6514 coulombs reading
limits (1 Year, 18˚C-28˚C)
20nC 20V 1nF 20.0000nC _______V 19.9915 to 20.0805nC
200nC 200V 1nF 200.000nC _______V 199.195 to 200.805nC
2µC 20V 100nF 2.00000µC _______V 1.97995 to 202.02005µC
20 µ C 200V 100nF 20.0000 µ C _______V 19.7995 to 20.2005 µ C
1
Nominal values.
2
Calculate actual voltage from applied charge and actual capacitance value: V = Q/C.