Loopback Assemblies

Seamless Diagnostics, Unmatched Precision: Explore Our Loopback Assemblies

Step into the future of diagnostic testing with our cutting-edge Loopback Assemblies. Crafted for reliability and precision, these assemblies are the go-to solution for assessing the functionality and performance of communication interfaces within electronic systems. Dive into the advantages, applications, and superior materials that set our Loopback Assemblies apart.

What is a Loopback Assembly?

A Loopback Assembly (Also known as a Terminator Plug or receptacle) is a customized diagnostic tool. The assembly will usually consist of an electrical connector that is used to connect the pins of a cable harness together, effectively “looping back” the signal within the cable. Behind the connector, pins or sockets may be “jumped” together using hook up wire, bend resistant Single Mode or Multi mode fiber optic cable, resistors, capacitors or diodes, or a combination of each. The ‘jumpers” are encased in and environmentally sealing “shorting can” style connector backshell. The purpose of using a loopback assembly in a cable harness or system can vary depending on the specific application, but some common reasons include:


  1. Efficient Diagnostic Testing: Loopback assemblies are often used for testing and diagnostics to ensure that the cable harness is functioning properly. By looping back the signal within the cable, technicians can perform various tests to check for continuity, signal strength, and other important electrical characteristics. This can help identify any issues with the cable harness or the connected equipment.
  2. Signal Isolation: In some cases, loopback plugs may be used to isolate signals within a cable harness. By connecting the pins of the cable together, the loopback plug can prevent signals from traveling beyond a certain point in the cable, which can be useful in troubleshooting or testing specific sections of the cable harness.
  3. Safety: In some cases, loopback plugs may be used as a safety feature to prevent accidental shorts or other electrical issues. By connecting the pins of the cable together, the loopback plug can help ensure that the cable harness is not accidentally connected to the wrong equipment or wired incorrectly.


Overall, loopback, terminatory assemblies are a simple but effective tool for testing, diagnosing, and ensuring the proper functioning of cable harnesses. By connecting the pins of the cable together, loopback plugs / assemblies, can help prevent signal reflection, isolate signals, and ensure proper termination, all of which are critical for maintaining the reliability and performance of cable harnesses.


Trek’s rigorous testing ensures top-quality, reliable cable systems.

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