2-Wire Ohms Performance Tests; Offset Test - HP 3457A Service Manual

Performance Tests
2-Wire Ohms Performance Tests
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Figure 4-5. 2-Wire Ohms Performance Test Connections
4-30. 2-Wire Ohms Function
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Offset Test
4-31. Equipment Required. A low thermal short (copper wire) is required for this procedure.
1. Connect a low thermal short across the HP 3457A front panel HI and LO input terminals.
2. Set the HP 3457A to the 2-Wire Ohms Function, 30 Ohm range and the number of digits displayed
(DIGITS DISP) t o six.
3. Use the Test Record t o record the offset readings f o r the 30 Ohm, 300 Ohm, 3 Kohm, 30 Kohm,
300 Kohm, 3 Mohm and 30 Mohm ranges.
4. If any of the offset readings are beyond the limits specified in Table 4-7 and on the Test Record.
the instrument should be calibrated or repaired. Refer to Section V for calibration procedures.
5 . Remove the short from the front panel input terminals.
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Table 4-7. 2-Wire Ohms Offset Test Limits
30 ohm
300 ohm
3 Kohm
30 Kohm
300 Kohm
3 Mohm
30 Mohm
O H M
O H M
O H M
O H M
OHM
O H M
O H M
00.20335 ohm
000.2035 ohm
0.000207 Kohm
00.00027 Kohm
000.0010 Kohm
0.000014 Mohm
00.00083 Mohm
00.20335 ohm
000.2035 ohm
0.000207 Kohm
00.00027 Kohm
000.0010 Kohm
0.000014 Mohm
00.00083 Mohm