Section 2: General operation
Model 2450 Interactive SourceMeter® Instrument Reference Manual
2-96
2450-901-01 Rev. B/September 2013
Offset-compensated ohms
The voltage offsets because of the presence of thermal EMFs (V
EMF
) can adversely affect resistance
measurement accuracy. To overcome these offset voltages, you can use offset-compensated ohms.
See
Offset-compensated ohm calculations
(on page 4-20) for additional detail on calculating
offset-compensated ohms.
Setting offset-compensated ohms
Using the front panel:
This setting is only available from the front panel when the resistance measurement function is
selected.
1. Press the
MENU
key.
2. Under Measure, select
Settings
.
3. Next to Offset Comp, select
On
.
4. Select
HOME
to return to the operating display.
Using SCPI commands:
To enable offset-compensated ohms, send the command:
SENSe:RESistance:OCOMpensated ON
Using TSP commands:
To enable offset-compensated ohms, send the commands:
smu.measure.func = smu.FUNC_RESISTANCE
smu.measure.offsetcompensation = smu.ON
Source and measure using SCPI commands
The SCPI commands that set up the source functions are in the SOURce subsystem.
The source commands are specific to each source function (voltage or current). For example, to set
the range to 100 mA for the current function, you would send:
:SOURce:FUNCtion CURRent
:SOURce:CURRent:RANGe 1e-01
To set the range to 20 V for the voltage function, you would send:
:SOURce:FUNCtion VOLTage
:SOURce:VOLTage:RANGe 20
The SCPI commands that set up the measurement functions are in the SENSe subsystem.
The sense commands are also specific to each measure function (voltage, current, or resistance). For
example, to set the NPLC cycles to 0.5 for the current measurement function, you would send:
:SENSe:CURRent:NPLCycles .5
For the voltage measurement function, you would send:
:SENSe:VOLTage:NPLCycles .5
For the resistance measurement function, you would send:
:SENSe:RESistance:NPLCycles .5