Locating bad crimps

June 1, 1995
For the cable installer, crimping modular plugs is an important task. If this technique is done improperly, it can lead to hours of frustration trying to locate open and intermittent lines.

Al Contarino, L-Com Inc.

Problem

For the cable installer, crimping modular plugs is an important task. If this technique is done improperly, it can lead to hours of frustration trying to locate open and intermittent lines.

Solution

To verify that plugs were crimped correctly, first make a visual inspection; then, if necessary, check the cable with electronic test equipment.

Procedure

1) For the visual inspection, use a magnifier, loupe or microscope because flaws can be difficult to see with the naked eye.

2) Look at the plug from the front and check that the wires were trimmed with a sharp instrument to ensure no strands are sticking out past the insulation on the wires.

3) Check that the main strain relief is making tight contact with the cable jacket. All strain should be on the cable jacket, not on the wires.

4) If a secondary strain relief was used, make sure it was crimped properly and is seated on top of the wires.

5) With a magnification device, view the surface of all contacts. They should all be aligned parallel to each other, with no plastic burrs showing in the contact areas. If poor-quality tools or plugs were used, a burr of plastic can build up on the two outermost pins--pins 1 and 8 of an RJ-45 connector--during the crimping cycle. This burr will prevent proper contact with the mating jack.

Click here to enlarge image

Plastic burr built up on pin 1 of an RJ-45 connector during the crimping cycle will prevent proper contact with the mating jack.

Sponsored Recommendations

March 28, 2025
Bringing University of Tennesee's campus up to speed.
March 28, 2025
CommScope’s FiberGuide® Design Pro helps you design a complete fiber raceway for your data center or central office using 2D and 3D technology. This video guides you through the...
March 28, 2025
CommScope and Equinix work hand in hand to provide client connectivity across the globe