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Appendix B: Calibration
Model 2657A High Power System SourceMeter® Instrument Reference Manual
B-16
2657A-901-01 Rev. B/December 2012
Recommended calibration adjustment equipment
The table below contains the recommended equipment for the calibration adjustment procedures.
You can use alternate equipment as long as that equipment has specifications equal to or greater
than those listed in the table. When possible, test equipment specifications should be at least four
times better than corresponding Model 2657A specifications.
Description Manufacturer/model
Accuracy
Digital multimeter
DC voltage
180 V: ±130 ppm
450 V: ±110 ppm
1350 V: ±110 ppm
2700 V: ±110 ppm
DC current
0.9 nA: ±1200 ppm
9 nA: ±470 ppm
90 nA: ±360 ppm
900 nA: ±170 ppm
9
μ
A: ±100 ppm
90
μ
A: ±50 ppm
0.9 mA: ±50 ppm
1.8 mA: ±110 ppm
18 mA: ±110 ppm
108 mA: ±100 ppm
50
Ω
resistors (2)
Any suitable.*
Sample voltage divider**:
Ultra-stable resistor (qty 6), for voltage
divider 10 M
Ω
, 0.01%
Caddock USF271 -
10.0 Meg - 0.01% -
2ppm/°C
±110 ppm
Ultra-stable resistor (qty 1), for voltage
divider 200 k
Ω
, 0.01%
Caddock USF240 -
200K - 0.01% -
2ppm/°C
±110 ppm
* Used for contact check calibration. Before use, characterize with the resistance function of the digital multimeter.
** A voltage divider is needed only if the available digital multimeter cannot measure full scale values of the Model
2657A. The resistors (in the sample voltage divider circuit) are used to test signals with the recommended equipment >
1000 V. Before use, characterize the resistor to the uncertainty shown.
Calibration adjustment overview
The following topics contain an overview of the entire calibration adjustment procedure.
Parameter values
The full-scale parameters are actually 90% of full-scale as indicated (see the table contained in
(on page B-17)). Note that you cannot send a value of exactly 0 for the two zero
parameters. Instead, you must send a very small value, such as 1e-30 or -1e-30.
Sense modes
The table titled "Model 2657A calibration steps" in
(on page B-17) lists the sense
modes for the calibration steps. Note that each source and measure range (both voltage and current)
is calibrated using the LOCAL sense mode, but only the voltage source and measure ranges are also
calibrated using the REMOTE sense mode. In addition, the 200 V, 1500 V, 3000 V, and the 1 mA
source ranges are calibrated using the CALA sense mode.
Содержание 2657A
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