Keithley SourceMeter 2425, Service Manual

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1-4 Performance Verification Model 2425 Service Manual
Recommended test equipment
Table 1-1 summarizes recommended verification equipment. You can use alternate equip-
ment as long as that equipment has specifications comparable to those listed in Table 1-1.
Keep in mind, however, that test equipment uncertainty will add to the uncertainty of each
measurement. Generally, test equipment uncertainty should be at least four times better
than corresponding Model 2425 specifications. Table 1-1 lists the specifications of the
recommended test equipment, including maximum allowable uncertainty for alternate test
equipment (shown in parentheses).
Table 1-1
Recommended verification equipment
Description Manufacturer/Model Specifications
Digital Multimeter Hewlett Packard
HP3458A
DC Voltage 1 1V:
10V:
100V: ±5.6ppm
±4.3ppm
±6.3ppm
DC Current 2 10
μ
A:
100
μ
A:
1mA:
10mA:
100mA:
1A:
±25ppm
±23ppm
±20ppm
±20ppm
±35ppm
±110ppm
Resistance Calibrator Fluke 5450A Resistance
2
1.9
Ω
:
19
Ω
:
190
Ω
:
1.9k
Ω
:
19k
Ω
:
190k
Ω
:
1.9M
Ω
:
19M
Ω
:
±65ppm (±460ppm)
±23ppm (±280ppm)
±10.5ppm (±230ppm)
±8ppm (±200ppm)
±7.5ppm (±195ppm)
±8.5ppm (±200ppm)
±11.5ppm (±180ppm)
±30ppm (±635ppm)
Precision Resistor 3 Isotec RUG-Z-1R00-0.1 1
Ω
, ±0.1%, 100W
1
90-day, full-range accuracy specifications of ranges required for various measurement points.
2
90-day, ±5°C specifications of nominal resistance values shown. Use actual values for tests. Maximum uncertainty of alternate test
equipment shown in parentheses.
3
Required for verification of 3A current range. Characterize resistor to ±300ppm or better using recommended DMM before ver-
ifying 3A current measurement range.