How to Use a Field Term Plug for Patch Cables

Written by Don Schultz, Senior Technical Marketing Specialist, Fluke Networks Certified Copper/Fiber CCTT, BICSI TECH, INSTC, INSTF Certified

Sometimes, you just have to go custom! Have you found yourself in the field needing a specific length of patch cable but don’t have one on hand and forgot your 8P8C (aka RJ45) crimp and termination tool? Perhaps you're tired of pre-made cables that are always the wrong length? Field termination plugs solve both problems and more. This guide walks you through exactly how to terminate a high performance patch cable with a field term plug, step by step.

Note on definitions: trueCABLE is aware that some items in the industry are incorrectly referenced due to habit. Therefore, the more common (but incorrect) term “Ethernet” will be used for copper twisted pair Category cable and likewise the incorrect term “RJ45” will be used for 8P8C modular male plugs. This is done for simplicity.

What Is a Field Termination Plug?

A field termination plug (also called a tool-less RJ45 or field term plug) is a Category rated modular connector designed to be terminated by hand in the field with minimal tools.

Field plug terminated solid copper Cat6A shielded patch cord

Here the advantages of field termination plugs over 8P8C (aka RJ45) plugs:

• The better choice for solid copper Ethernet Category cable due to their internal IDC (insulation displacement contact) prongs, which penetrate the conductors from right angles (which is important) when the cap is pressed closed.
• Dedicated crimp and termination tools are not required for field termination plugs, but note that you still require a cable cut and strip tool in addition to flush cutters.
• Field termination plugs help impedance match your patch cord to your structured cabling system.
• Backwards compatibility means Cat6A field termination plugs work with Cat5e, Cat6, and Cat6A solid or stranded copper twisted pair Category cable (aka Ethernet).
• Field termination plugs are Category rated and have an internal PCB (printed circuit board) tuned for Category performance.
• RJ45s require remembering a conductor color code order to wire properly, where field termination plugs have a pre-printed color coded conductor holder cap that makes wiring the correct way easy.
• Field termination plugs are far more forgiving than RJ45s when it comes to conductor insulation diameter and overall cable diameter fitment. Due to the IDC spring prong mechanism, field termination plugs “auto adjust” for various conductor thickness where RJ45s require careful selection to your cable to work properly or at all.

This guide will use the trueCABLE Cat6A Shielded Field Termination plug and the trueCABLE Cat6A Unshielded Field Termination plug as examples in various sections.
Here are some pictures that say a thousand words:

Field termination plug conductor holder cap showing color code pattern (unshielded version shown)

Field termination plug IDC prongs (unshielded version shown)

Field Term Plug vs. Standard RJ45 — When to Use Each

No doubt in your shopping around you might have wondered exactly what the use case is for field termination plugs as opposed to RJ45s and why you would pick one over the other. This table will help clear that question up!

When you go to use a patch cord, the best kind are factory produced pre-certified component rated stranded copper patch cords. If you don’t have one of those, and you only have solid copper Ethernet to work with, then you are best off terminating your patch cord with field termination plugs. Why? Please see Terminating Pass-Through RJ45 Connectors onto Solid Copper Ethernet Cable -- A Really Bad Idea?

Field plug terminated cable plugging into a Ethernet switch

Not everything is roses, however. Given that field termination plugs are much more complex than RJ45 plugs, the cost per plug is considerably higher. In addition, field termination plugs may pose physical compatibility challenges in tight device housings like Wi-Fi access points and cameras due to their length.

What You'll Need

So, let’s assume you decide to use field termination plugs and need to terminate them to your cabling. What will you require to do that? Not too much is required, and there is an optional tool and accessory (both quite helpful) if you decide to purchase them.

• 2 x field term plugs (trueCABLE Cat6A, shielded or unshielded as appropriate)
• Bulk Ethernet cable (Cat6A recommended — shielded if using shielded plug)
• Cable stripper or utility knife
• Scissors or flush cutters
• Channel locks (parallel jaw pliers optional)
• Copper fabric strips (optional)
• That's it — no crimp tool, no punchdown tool

Step-by-Step: How to Terminate a Patch Cable with a Field Term Plug (Shielded Version Example)

Pre-Step — Cut your cable to length

Be sure to add a couple of inches at each end in case you make a termination mistake!

Step 1 — Place Locking Strain Relief Boot onto Cable

Reverse the boot and put it on the wrong way

Slide the boot until it stops and cut at the stop point (green line)

Place the boot on the right way, and slide it down out of your way

Step 2 — Strip the Cable Jacket

Strip approximately 1.5 inches of the outer jacket from each end of the cable. For shielded cable, fold the foil shield back over the jacket and wrap the drain wire around it before proceeding. Alternatively, use our copper fabric strips to terminate your cable shield by removing the shield and tacking the drain wire down instead.

Avoid nicking the individual conductors

Using the trueCABLE Cut & Strip tool to place a score on the cable jacket

Break cable jacket at the score

Remove the center spline if your cable has one. Copper fabric strip shown applied to make contact with drain wire, after removal of cable shield.

Remove the sliding latch security tab. Do not lose it!

Step 3 — Untwist and Lace Pairs into Conductor Holder Cap

First, it is important to decide which color code sequence you wish to use. Two options are available -- T568A and T568B. From a performance standpoint, they perform identically. Pick one, and stick with it at both ends of your cable. The conductor holder cap is color coded to show you the proper conductor lacing sequence.

Lace conductor holder cap following the color code you have chosen. We settled on T568B, for no particular reason.

Step 4 — Trim the Conductors from Side of Conductor Holder Cap

Once arranged in order, trim all conductors. Use flush cutters for a clean, precise cut.

Flush cut conductors from cap sides and front

It is important to confirm and then re-confirm the conductors are in the correct slots BEFORE you flush cut. If you accidentally seat a conductor into the wrong slot for the color code you are using and then flush cut it, you will need to start over from Step #1!

Step 5 — Insert Conductor Holder Cap into Plug Body

Place the conductor holder cap into the plug body, being sure to match up the notch and key as shown. Press downward firmly on the conductor holder cap to pre-seat the conductors. Keep pressure on the cap!

Take note of notch in conductor holder cap and key inside jack body

Place conductor holder cap into plug body and press downward to pre-set the conductors

Step 6 — Close and Lock the Plug

Close the plug lid while keeping pressure on the conductor holder cap. The IDC contacts inside will pierce the conductor insulation and make contact. Once the lid is closed, firmly shut the lid with channel lock or parallel jaw pliers. Finally, slide the locking strain relief boot up the cable and over the rear plug body to lock it.

Close plug lid

Firmly snap lid shut at point shown (between green lines) using channel lock pliers or the trueCABLE Parallel Pliers tool

Second view of snapping lid firmly shut. If using trueCABLE pliers, use the inside jaws.

While holding the plug lid down, slide locking strain relief boot onto plug body to keep it closed. Note the Wi-Fi symbols and match them up.

Plug locked closed using the locking strain relief boot

Step 7 — Test the Cable

Use a cable tester to, at minimum, verify continuity and correct wiring on both ends. A more advanced tester that measures speed is recommended if you have access to one. For a description of what testers trueCABLE recommends and what the differences are, please see Ethernet Cable Testers: Which Is Best for My Application?

Two Ethernet switches, directly connected with a field terminated patch cord

Common Mistakes to Avoid

Here are some common mistakes and solutions:

• Nicking a conductor is a major risk when scoring your cable jacket so you can strip it off. If you nick a conductor you must start over. Tip: If you scored shielded cable and sliced through the cable shield at any point while doing it, you likely nicked a conductor.
• Crossing or transposing conductors — always double-check that the conductors are seated into the correct conductor holder cap slots for the given color code you are using before you flush cut them off and put the conductor holder cap into the plug body.
• Once you insert the conductor holder cap into the body, press downward firmly to pre-seat the conductors. If you do not do this, there is a risk a conductor will become misaligned when you close the field term plug body lid and this will result in a crushed cap or even a broken hinge!

Pro Tips for Clean Results

Getting professional results is not difficult, but does require attention to detail:

• Make both ends at once before closing either — this speeds the process and makes both ends easier to compare.
• Label your patch cables, especially if they are different lengths. You don’t want to end up guessing which cable goes where.
• Store unused field term plugs in a sealed bag — dust in the IDC contacts can affect termination quality.
• For shielded applications, ensure the drain wire and/or foil is making contact with the plug's grounding mechanism. The easiest way to accomplish this is to remove the foil shield from the cable and then wrap the drain wire around the cable jacket and tack it down with a conductive adhesive copper fabric strip. You can use the older method of folding the cable shield backwards and wrapping the drain wire around it, but this often gets in your way and adds unwanted thickness to your cable.

Conclusion

There you have it! Now you know how and why field termination plugs can add a great deal to your installation. Field termination plugs make custom and high performance patch cables accessible anywhere, with minimal tools and professional results when done correctly. With that, we will say….

HAPPY NETWORKING!

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