User manual

Series 3700 System Switch/Multimeter Reference Manual Section 14: Verification
3700S-901-01 Rev. C / July 2008 14-19
Verifying 4-wire resistance
Check the normal resistance function by connecting accurate resistance values
to the Series 3700 analog backplane connector and verifying that the displayed
readings fall within specified limits.
CAUTION Do not exceed 300V peak between INPUT HI and INPUT LO
because instrument damage may occur.
To verify 4-wire resistance accuracy:
1. Using shielded, Teflon-insulated or equivalent cables in a 4-wire
configuration, connect the Series 3700 INPUT and SENSE pins to the
calibrator as shown for 100 to 10M ranges.
2. Set the calibrator for 4-wire resistance with external sense on.
3. Select the Series 3700 4-wire resistance function.
4. Select the SLOW integration rate with the RATE key.
5. Set the Series 3700 for the 100 range, and make sure the FILTER is on.
Enable OC+ (offset-compensated ohms). Use OC+ for 100 and 1k range
verification only. See Enabling/disabling offset-compensated ohms in the
User's manual.
6. Recalculate reading limits based on actual calibrator resistance values.
7. Source the nominal full-scale resistance values for the 100 to 10M
ranges summarized in the 4-wire resistance verification data (on page 14-
20) table. Recalculate the limits based on the actual value of the resistor and
verify the reading is within the calculated limits.
Figure 14-9: Resistance verification