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View the measurements on the front-panel graph

To view the leakage current measurements on the front-panel graph:
1.  Press the MENU key.
2.  Under Views, select Graph.
3.  Select the Scale tab.
4.  Under Y-Axis, next to Scale Format, select Log.
5.  Under X-Axis, next to Auto Scale, select On.
6.  Select the Graph tab to view the graph.

Figure 5

 shows the front-panel graph for this application.

Set up the leakage current application using SCPI commands

The following SCPI code performs a capacitor leakage measurement by sourcing 20V and measuring the resulting leakage current. 
The Duration Loop trigger model template applies the voltage for 60 seconds and makes measurements at 200ms intervals. After the 
duration time, the capacitor is discharged at 0V and the output is turned off.

Send the following commands for this example application:

Command

Description

*RST
:SOUR:FUNC VOLT
:SOUR:VOLT 20
:SOUR:VOLT:ILIMIT 0.01
:SENSE:FUNC “CURR”
:ROUT:TERM REAR
:CURR:RANG:AUTO ON
:SENSE:CURR:NPLC 1
:TRIG:LOAD:LOOP:DUR 60, 0.2
:OUTP ON
:INIT
*WAI
:TRAC:ACT? “defbuffer1”
:TRAC:DATA? 1, <n>, “defbuffer1”, READ, REL
:SOUR:VOLT 0
:OUTP OFF

Reset the Model 2450.
Set to source voltage.
Set the source voltage to 20 V.
Set the current limit to 10 mA.
Set the instrument to measure current.
Set to use rear-panel terminals.
Set the current range to autorange.
Set the number of power line cycles to 1.
Load the Duration Loop trigger model to run for 60 s at 200 ms intervals.
Turn on the output.
Trigger the measurement.
Wait for the measurement to finish.

<n>

 is the queried number of readings.

Query the number of readings in 

defbuffer1

 and return the readings and time.

Discharge the capacitor to 0 V.
Turn off the output.

Set up the leakage current application 

using TSP commands

NOTE:

 The following 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 the SCPI 

command set. You must select the TSP command set before 
sending 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

.

The following TSP code performs a capacitor leakage 

measurement by sourcing 20V and measuring the resulting 
leakage current. The Duration Loop trigger model template 
applies the voltage for 60 seconds and makes measurements 
at 200ms intervals. After the duration time, the capacitor is 
discharged at 0V and the output is turned off.

After the code is executed, the measurement results are 

displayed in the Instrument Console of Test Script Builder. 
From the Instrument Console, you can copy the data into a 
spreadsheet for graphing.

Send the following commands for this example application:

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