HP 3457A Service Manual page 71

Performance Tests
Rear Input Performance Tests (Standard Instrument) Cont'd
3457A
2. Use the Test Record to record the offset readings for the 30 Ohm, 300 Ohm, 3 Kohm, 30 Kohm,
300 Kohm, 3 Mohm and 30 Mohm ranges.
3. If any of the offset readings are beyond the limits specified in Table 4-13 and on the Test Record,
the instrument should be calibrated or repaired. Refer to Section V for calibration procedures.
34578 3457A | 3457A | 90 day limits | 1 year Limits
Input Range | Set Up
Short 30 ohm OHM 00.20335 ohm 00.20335 ohm
Short |300 ohm OHM 000.2035 ohm 000.2035 ohm
Short 3 Kohm | OKM 0.000207 Kohm | 0.000207 Kohm
Short 30 Kohm | OHM 00.00027 Kohm | 00.00027 Kohm
Short |300 Kohm | OHM 000.0010 Kohm | 000.0010 kKohm
Short 3 Mohm | OHM 0.000014 Mohm | 0.000014 Mohm
Short 30 Mohm | OHM 00.00083 Mohm | 00.00083 Mohm
Table 4-13. 2-Wire Ohms Offset Test Limits (Rear Terminals)
4-47. 4-Wire Ohms Function - Offset Test
4-48, Equipment Required. A low thermal short (copper wire) is required for this procedure.
4-16
1, Set the HP 3457A to the 4-Wire Ohms Function (OHMF) and the number of digits displayed
(DIGITS DISP) to six.
2. Use the Test Record to record the offset readings of the 30 Ohm, 300 Ohm, 3 Kohm, 30 Kohm,
300 Kohm, 3 Mohm, and 30 Mohm ranges.
3. If any of the offset readings are beyond the limits specified in Table 4-14 and on the Test Record,
the instrument should be calibrated or repaired. Refer to Section V for calibration procedures.
3457A 3457A |3457A | 90 day Limits | 1 year Limits
Input Range | Set Up
Short 30 ohm OHMF | 00.00335 ohm 00.00335 ohm
Short 300 ohm OHMF 000.0035 ohm 000.0035 ohm
Short 3 Kohm | OHMF | 0.000007 Kohm | 0.000007 Kohm
Short 30 Kohm | OHMF | 00.00007 Kohm | 00.00007 kKohm
Short | 300 Kohm | OHMF | 000.0008 Kohm | 000.0008 Kohm
Short 3 Mohm | OHMF | 0.000014 Mohm | 0.000014 Mohm
Short 30 Mohm | OHMF | 00.00083 Mohm | 00.00083 Mohm
Table 4-14. 4-Wire Ohms Offset Test Limits (Rear Terminals)