Keithley SourceMeter 2470, Руководство пользователя

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In this section:
Introduction .............................................................................. 5-1
Equipment required .................................................................. 5-2
Set up remote communications ................................................ 5-2
Device connections .................................................................. 5-2
Measuring leakage current ....................................................... 5-4
Measuring insulation resistance ............................................... 5-9
Introduction
Tests to measure the leakage current or insulation resistance of a device are very similar. In both
cases, you can apply a fixed bias voltage and measure the resulting current. Depending on the
device under test, the measured current is typically very small, usually less than 10 nA.
This application consists of two examples that demonstrate:
•
How to use the 2470 to perform leakage current measurements on a capacitor.
•
How to use the 2470 to measure insulation resistance between the two conductors of a
coaxial cable.
The leakage current application applies a voltage for a specified period. This soak period allows time
for the device to charge so that you can make a settled-current measurement. In this application, the
resulting current is measured the entire time the device is biased. In other cases, only one reading is
required and may be made at the end of the soak period. The application ends by applying 0 volts to
discharge the device. The results are returned in units of amperes.
The insulation-resistance application applies voltage and makes a specified number of readings with
a set delay between each reading. This allows the measurement to settle, but it is easier to specify
exactly how many readings are made. Insulation typically settles much faster than a capacitor device.
The results are returned in units of ohms.
The following topics describe how to do these applications from the front panel. They also show how
to do them using a remote interface with SCPI and Test Script Processor (TSP
®
) commands.
Section 5
Leakage current and insulation resistance