10 TEGAM WAY • GENEVA, OHIO 44041 • 440-466-6100 • FAX 440-466-6110
•
1-2
INSTRUMENT DESCRIPTION
Accuracy:
Accuracy of all resistance measurements are affected by the
test leads unless 4-wire Kelvin measurement connections are
used.
Range
Full
Scale
(Ω)
4-Wire
Kelvin
3-Wire
2-Wire
Test
Current
1
0.199999
±0.05%
±15 LSD*
Not
Specified
Not
Specified
50 mA
2
1.99999
±0.05%
±2 LSD*
Not
Specified
Not
Specified
50 mA
3
19.9999
±0.05%
±1 LSD*
Not
Specified
Not
Specified
50 mA
4
199.999
±0.05%
±1 LSD*
±0.05%
±1 LSD*
±0.05%
±1 LSD*
1
0.5 mA
5
1999.99
±0.05%
±1 LSD*
±0.05%
±1 LSD*
±0.05%
±1 LSD*
1
0.5 mA
*LSD= Least Significant Digit
1
Does not include test lead or contact resistance
Table 2: Specifications
When making low resistance measurements, variables such
as test lead resistance, contact resistance of all the
connections, as well as ambient temperature will affect the
measurement accuracy. When using 4-wire connections,
these effects are minimized.
When making 2 and 3-wire measurements, even if all the test
leads are of known value, the variables of temperature and
contact resistance remain unpredictable and will add to the
uncertainty of the measurement. The R1L-D1 accuracy is not
specified for 2 and 3-wire mode on ranges 1 to 3. This does
not mean that the R1L-D1 cannot be operated in these
ranges, but the user needs to be aware of the issues and
compensate for the variables that affect measurement
accuracy outside of the instrument. Errors that can be
introduced at these resistance levels will likely result in
measurement accuracies beyond the intrinsic accuracy of the
R1L-D1. Therefore the accuracy specification is not given.
3-wire operation balances the resistance of one lead against a
second lead, compensating for the lead resistance as long as
the leads are identical. Therefore in 3-wire mode, the test
leads and their connections must be of identical resistance
