Figure 2. System Level Connection, Typical
1
2
Safety Interlock Connector
Test Fixture Enclosure
Operator Access Door
Mechanical Detection Switches
Mechanical detection switch is actuated
by operator access point
3
4
1. Safety Interlock Input
2. Safety Interlock Ground
3. Safety Interlock Pass Thru - Input
4. Safety Interlock Pass Thru - Ground
Related Information
Fore more information about the Safety Interlock, refer to the NI DC Power Supplies and
SMUs Help.
Testing the Safety Interlock
Mechanical Detection Switch Recommendations
•
Use high-reliability, fail-safe, normally open mechanical detection switches on all access
points to the test fixture enclosure.
•
Use two normally open switches wired in series so that a single switch failure does not
compromise safety protections.
•
Isolate switches so the operator cannot trigger or bypass the switches without the use of a
tool.
•
Ensure the switches' certifications meet your test application requirements. NI
recommends UL-certified safety switches to ensure reliability.
•
Install the switches in accordance with the switch manufacturer specifications.
•
Test the switches periodically to ensure proper implementation and reliability.
Safety Guidelines for System Operation
Caution
Hazardous voltages of up to the maximum voltage of the PXIe-4135 may
appear at the output terminals if the safety interlock terminal is closed. Open the
safety interlock terminal when the output connections are accessible. With the safety
interlock terminal open, the output voltage level/limit is limited to ±40 V DC, and
PXIe-4135 Getting Started Guide
|
© National Instruments
|
7
