Tektronix Keithley SourceMeter 2450, User Manual

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Section 9: Measuring I-V characteristics of solar cells Model 2450 Interactive SourceMeter® Instrument User's Manual
9-6 2450-900-01 Rev. A / June 2013
Setting up the solar cell I-V sweep using SCPI commands
The example sequence of SCPI commands generates an I-V sweep on a solar cell. You must make
the appropriate changes so it will run in your programming environment.
In this example, the voltage is swept from 0 V to 0.55 V in 56 steps and the resulting solar cell current
is measured. The current and voltage measurements are stored in default buffer 1 (
defbuffer1
).
Send the following commands for this example application:
Command Description
*RST
SENS:FUNC "CURR"
SENS:CURR:RANG:AUTO ON
SENS:CURR:RSEN ON
SOUR:FUNC VOLT
SOUR:VOLT:RANG 2
SOUR:VOLT:ILIM 1
SOUR:SWE:VOLT:LIN 0, 0.55, 56, 0.1
:INIT
*WAI
TRAC:DATA? 1, 56, "defbuffer1", SOUR, READ
•
Reset the Model 2450.
•
Set to measure current.
•
Set to measure with autorange enabled.
•
Set to use 4-wire sense mode.
•
Set to source voltage.
•
Set to the 2 V source range.
•
Set the current limit to 1 A.
•
Set the sweep to sweep voltage from 0 to 0.55 V in 56
steps.
•
Initiate the sweep.
•
Wait until the sweep is finished.
•
Read the source and measure values from
defbuffer1
.
Setting up the solar cell I-V sweep using TSP commands
The following example TSP code is designed to be run from Keithley Instruments Test Script Builder
(TSB). TSB is a software tool included on one of the CD-ROMs that came with your Model 2450.
You can install and use TSB to write code and develop scripts for TSP-enabled instruments.
Information about how to use TSB is in the online help for TSB and in the “Introduction to TSP
operation” section of the Model 2450 Reference Manual.
To use other programming environments, you may need to make changes to the example TSP code.
By default, the Model 2450 is configured to use SCPI commands. You must select the TSP command
set before attempting to send TSP commands to the instrument.
To enable TSP commands:
1. Press the MENU key.
2. Under System, select Settings .
3. Select the button next to Command Set and select TSP .
4. You are prompted to reboot. Select Yes .
In this particular example, a linear voltage sweep is configured to output voltage from 0 V to 0.55 V in
56 steps, while measuring the resulting current from the solar cell.