30
Agilent E1412A Multimeter Application Information
Removing Field
Wiring Resistance
Errors
in 2-Wire Ohms
Measurements
Field wiring can cause an offset error in 2-wire resistance measurements.
You can use the following procedure to minimize offset errors associated
with field wiring resistance in 2-wire ohms measurements. You short the
field wiring at the DUT location and measure the 2-wire lead resistance.
This value is subtracted from subsequent DUT 2-wire ohms measurements.
There are two ways to effectively null out the lead resistance. The first way
is to characterize your field lead resistance by shorting the leads at the DUT
location and measure and record the lead resistance. Then enable the math
operation and store the 2-wire lead measurement value using the
CALCulate:NULL:OFFSet <
value
>
command (
CALC:STATe
must be
ON
to
do this).
The following program shows SCPI examples used to store a
NULL
value.
CONF:RES
Set to 2-wire ohms function.
Short the lead resistance at the DUT location.
READ?
Measure the 2-wire ohms lead resistance.
Enter lead resistance value into computer.
CALCulate:FUNCtion NULL
Set math operation to NULL.
CALCulate:STATe ON
Turn math operation ON.
CALCulate:NULL:OFFSet <
value
>
Store the NULL offset value.
Subsequent 2-wire ohms measurements will subtract the null offset value
from the measurement thereby removing the lead resistance from the
measurement.
The second way to store the 2-wire lead resistance as the
NULL
offset value
is to let the multimeter automatically do this with the first measurement. The
first measurement made after
CALCulate
function is set to
NULL
and the
STATe
is set to
ON
stores the measured value as the null offset.
CONF:RES
Set to 2-wire ohms function.
Short the lead resistance at the DUT location.
CALCulate:FUNCtion NULL
Set math operation to NULL.
CALCulate:STATe ON
Turn math operation ON.
READ?
Measure the 2-wire ohms lead resistance.
Enter lead resistance value into computer. The value is automatically
stored in the multimeter's null offset register.
Remove the short from the lead resistance at the DUT location
and connect leads to your DUT.
READ?
Make a 2-wire ohms resistance measurement.
Enter lead resistance value into computer. The NULL value is
subtracted from the measurement to more accurately provide the
DUT resistance.
Summary of Contents for Agilent E1412A
Page 2: ......
Page 10: ...8 Contents Notes...
Page 14: ...12 Notes...
Page 15: ...13 Notes...
Page 16: ...14 Notes...
Page 26: ...24 Agilent E1412A Multimeter Module Setup Chapter 1 Notes...
Page 194: ...192 Agilent E1412A Multimeter Error Messages Appendix B Notes...
Page 201: ...Index 199 Index Agilent E1412A User s Manual and SCPI Programming Guide...
