Hioki RM3544 - 4.1 Zero Adjustment

4.1 Zero Adjustment
44
Perform zero-adjustment in the following circumstances:
• The measured value is not cleared due to thermal EMF or other factors.
 The measured value will be adjusted to zero. (Accuracy is not affected by whether or
not the zero adjustment is performed.)
• Four-terminal connection (called Kelvin connection) is difficult.
 The residual resistance of the two-terminal connection wires will be canceled.
For more information about how to perform zero-adjustment properly, see "Appendix 6 Zero
Adjustment" (p. A8).
Before Zero Adjustment
• Execute zero adjustment when the ambient temperature has changed, or when a mea-
surement lead is replaced after zero adjustment was performed. However, when perform-
ing zero-adjustment is difficult, for example when using the L2102 or L2103 Pin Type
Lead, perform zero-adjustment using the standard included L2101 Clip Type Lead or sim-
ilar lead and then switch to the pin type lead to perform measurement.
• Zero adjustment should be executed in each range to be used. Perform zero-adjustment
for the current range only when setting the range manually or for all ranges when using
auto-ranging.
• Zero adjustment values are retained internally even when the instrument is turned off.
They are also saved with panels. You can also elect not to load zero-adjustment values
from panels.
See: "6.1 Saving Measurement Conditions (Panel Save Function)"(p.72)
"6.2 Loading Measurement Conditions (Panel Load Function)"(p.73)
• Zero-adjustment can be performed even when the EXT I/O 0ADJ signal is ON (when
shorted with the EXT I/O connector’s ISO_COM pin).
• Although resistance of -3%f.s. to 50%f.s. can be canceled in each range, try to keep the
canceled resistance to 3%f.s. (f.s.=30,000dgt.) The zero-adjustment range can be
changed to TIGHT (-3%f.s. to 3%f.s.).
See: "Changing the zero-adjustment range" (p. 47)
• If a resistance that is smaller than the resistance value when zero-adjustment was per-
formed is measured, the measured value will be negative.
Example: If you set an offset of 20 m for the 300 m range
If you measure 10 m, -10 m will be displayed.
4.1 Zero Adjustment