Section 2: General operation
Model DMM7510 7½ Digit Graphical Sampling Multimeter Reference Manual
2-112
DMM7510-901-01 Rev. B / May 2015
Enabling or disabling dry circuit ohms
Dry circuit ohms is only available for the 4-wire resistance function.
When the dry circuit ohms feature is enabled, DRYCR is displayed to the right of the measurement on
the front panel of the instrument.
With 4-wire measurement 1 to 100 k
Ω
ranges and dry circuit 1 to 10 k
Ω
ranges, thermal voltages in
the test leads or device under test can create measure errors. To eliminate the thermal offset, offset
compensation is automatically enabled when you enable dry circuit ohms.
When offset compensation is enabled, two measurement phases are made. The first is with the I
off
test current, which is sourced from HI and LO and measured across the Sense HI and Sense LO
terminals. The second measurement is measured across Sense HI and Sense LO with an I
on
test
current from HI and LO. The difference between the I
on
and I
off
measurements is applied as an offset
to eliminate any thermal voltages.
When the dry circuit ohms attribute is enabled, the offset-compensated ohms attribute is
automatically enabled (OCMP displayed to the right of the measurement). If you do not wish to use
offset-compensated ohms, after setting dry circuit ohms, disable offset-compensated ohms.
From the front panel:
1. Press the
FUNCTION
key.
2. Select
4W Res
.
3. Press the
MENU
key.
4. Under Measure, select
Settings
.
5. Swipe to scroll down.
6. Set Dry Circuit to
ON
to enable or
OFF
to disable.
7. Press the
HOME
key
to return to the measurement display.
Using SCPI commands:
Send the commands:
:SENSe:FUNCtion "FRES"
:SENSe:FRES:DCIRcuit ON
Using TSP commands:
Send the commands:
dmm.measure.func = dmm.FUNC_4W_RESISTANCE
dmm.measure.drycircuit = dmm.ON
