Keithley 2657A User Manual

Model 2657A High Power System SourceMeter® Instrument Reference Manual Appendix B: Calibration
2657A-901-01 Rev. B/December 2012 B-3
Recommended verification equipment
The following table summarizes recommended maximum allowable test equipment uncertainty for
verification points. Total test equipment measurement uncertainty should meet or be less than the
listed values at each test point. Generally, test equipment uncertainty should be at least four times
better than corresponding Model 2657A specifications.
Description Manufacturer/model Accuracy
Digital multimeter DC voltage 100 V: ±180 ppm
180 V: ±130 ppm
250 V: ±160 ppm
450 V: ±110 ppm
750 V: ±160 ppm
1350 V: ±110 ppm
1500 V: ±160 ppm
2700 V: ±110 ppm
Digital multimeter (continued) DC current 0.5 nA: ±2000 ppm
0.9 nA: ±1200 ppm
5 nA: ±650 ppm
9 nA: ±470 ppm
50 nA: ±450 ppm
90 nA: ±360 ppm
500 nA: ±260 ppm
900 nA: ±170 ppm
5 μA: ±130 ppm
9 μA: ±100 ppm
50 μA: ±51 ppm
90 μA: ±50 ppm
0.5 mA: ±51 ppm
0.9 mA: ±50 ppm
1 mA: ±170 ppm
1.8 mA: ±110 ppm
10 mA: ±170 ppm
18 mA: ±110 ppm
60 mA: ±150 ppm
108 mA: ±100 ppm
Sample voltage divider*:
Ultra-stable resistor (qty 6), for
voltage divider 10 MΩ, 0.01%
Caddock USF271 -
10.0 Meg - 0.01% -
2ppm/°C
±110 ppm
Ultra-stable resistor (qty 1), for
voltage divider 200 kΩ, 0.01%
Caddock USF240 -
200K - 0.01% -
2ppm/°C
±110 ppm
* A voltage divider is needed only if the available meter cannot measure full scale values of the Model 2657A. The
resistors (in the sample voltage divider circuit) are used to test signals > 1000 V with the recommended equipment.
Before use, characterize the resistor to the uncertainty shown.
Verification limits
The verification limits stated in this section have been calculated using only the Model 2657A one-
year accuracy specifications, and they do not include test equipment uncertainty. If a particular
measurement falls outside the allowable range, recalculate new limits based both on the Model
2657A specifications and corresponding test equipment specifications.

Keithley 2657A Specifications

General

Brand	Keithley
Model	2657A
Category	Measuring Instruments
Language	English