Keithley SourceMeter 2425, Service Manual

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Model 2425 Service Manual Performance Verification 1-15
4. Verify output current accuracy for the 3A range. Be sure to:
• Select the 3A source range.
• Set the Model 2425 output current to the correct 3A output value.
• Verify that the multimeter reading is within the 3A range limits given in Table 1-5.
(Since the value of the 1
Ω
resistor value is assumed to be the same as its nominal
value, the DMM voltage reading is the same as the sourced current.)
5. Repeat the procedure for a negative 3A current output value.
6. Repeat the entire procedure using the rear panel INPUT/OUTPUT jacks. Be sure to
select the rear panel jacks with the front panel TERMINALS key.
Table 1-5
Output current accuracy limits
Model 2425
source range
Model 2425
output current setting
Output current limits
(1 year, 18°C to 28°C)
10mA
100mA
1mA
10mA
100mA
1A
3A
1
10.0000mA
100.000mA
1.00000mA
10.0000mA
100.000mA
1.00000A
3.00000A 9.9947 to 10.0053mA
99.949 to 100.051mA
0.99946 to 1.00054mA
9.9935 to 10.0065mA
99.914 to 100.086mA
0.99893 to 1.00107A
2.99543 to 3.00457A
1
See separate procedure for 3A range. DMM voltage reading is same as sourced current.