HP 3457A Service Manual page 85

Operational Verification Tests
4-Wire Ohms Operational Verification Tests Cont'd
34578 3457A |3457A | 90 day Limits | 1 year Limits
Input Range | Set Up
Short 3 Kohm | OHMF | 0.000007 Kohm | 0.000007 Kohm
Short 30 Kohm | OHMF | 00.00007 Kohm | 00.00007 Kohm
Short |300 Kohm | OHMF | 000.0008 Kohm | 000.0008 Kohm
Table 4-27. 4-Wire Ohms Offset Test Limits
Figure 4-18. 4-Wire Ohms Operational Verification Test Connections
4-86. 4-Wire Ohms Function - Gain Test
3457A
4-87. Equipment Required. Resistance Standards of 3 Kohms (+ .001%), 30 Kohms (+ 001%) and
300 Kohms (+ ,001%) are required for this procedure.
I. Set the HP 3457A to the 4-Wire ohms function (OHMF) and the number of digits displayed (DIGITS
DISP) to six.
2. Connect the appropriate Resistance Standard to the HP 3457A front panel input terminals as shown
in Figure 4-18.
3. Use the Test Record to record the resistance readings for the 3 Kohm, 30 Kohm and 300 Kohm
ranges.
4. If any of the readings are beyond the limits specified in Table 4-28 and on the Test Record, the in-
strument should be calibrated. Refer to Section V of this manual for calibration procedures.
5. Remove the Resistance Standard from the HP 3457A front panel input terminals.