Keithley SourceMeter 2600 Series Reference Manual page 259

Series 2600 System SourceMeters Reference Manual
Interlock (Models 2612/2612)
Overview
The Model 2611/2612 Digital I/O Port provides an Interlock line for use with a test
fixture switch. When properly used, the output of the SourceMeter will turn OFF
when the lid of the test fixture is opened. See
information when using a test fixture.
CAUTION
Operation
When on the 200V source range, the output of the Model 2611/2612 SourceMeter
can only be turned on when the Interlock line is pulled high through a switch to
+5V as shown in
and the Interlock line goes low, turning the output of the Model 2611/2612
SourceMeter off. The output will not be automatically turned on when the Interlock
line is set high. The output cannot be turned back on until the Interlock line is set
high.
A signal of > 3.4V @ 24mA (absolute maximum of 6V) must be externally applied
to this pin to insure 200V operation. This signal is pulled down to chassis ground
with a 10kΩ resistor. 200V operation will be blocked when the INTERLOCK signal
is < 0.4V (absolute minimum of -0.4V).
If the Interlock line is switched excessively, (more than 10,000
times), its reliability may be reduced. Where the Interlock is
used for safety, it should be serviced regularly to ensure
proper operation.
Figure 10-4. If the lid of the test fixture opens, the switch opens,
Return to Section 10 topics
Digital I/O Port 10-11
Section 3 for important safety
2600S-901-01 Rev. A / May 2006