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RJ45 Cable Termination: High Quality Helps Ensure High Performance

Sylvia Feng

When it comes to industrial Ethernet network installation, field termination—the onsite preparation of each end of each cable and then joining it securely to an RJ45 connector—can be among the most vulnerable steps in the process. With eight conductors per cable and potentially hundreds of cables in a midsized installation, occasional errors are not uncommon, which can lead to intermittent data failure and interruptions that are often challenging to track, further adding to downtime and frustration. Of course, best practice dictates that every termination be tested upfront, and estimates suggest that resulting rework rates are as high as 8-10%.


When installing a new network in machine building or other applications where there is a relatively high volume of terminations to be done at once or on an ongoing basis, using an experienced, technically adept technician is highly desirable. Unfortunately, many operators are finding that network installation is one of those industries suffering from attrition-driven brain drain, with large numbers of experienced personnel moving toward retirement and fewer technically skilled individuals coming up to take their place.

 

While this trend suggests that there could be an ongoing uptick in the frequency of issues caused by improper terminations, it is important to realize that many terminations are not done en masse, but are done more as “onesies twosies,” often by maintenance personnel repairing, replacing or installing an individual cable in an onsite network. With potentially long gaps between the need for them to perform each onsite termination, there is less of a chance to develop expertise, and a relatively steep learning curve each time.

 

In addition to quality, termination time is an important factor, whether in high volume installation or when conducting maintenance on a smaller number of cables. With standard procedures, proper termination can take five minutes or more, even when performed by highly experienced personnel. This can add significantly to installation times and cost where high numbers of terminations must be made, and can also impact the efficiency of maintenance teams who likely take longer still.

 

Ethernet Cable Terminations Can Be Faster, Easier and Surer

These observations suggest that there is a valuable opportunity to consider employing some alternative industrial Ethernet cable termination techniques, often using different types of connector systems. Fortunately, there are a number of options to consider, with different design concepts potentially increasing ease, speed and surety.

 

For example, an insulation displacement contact (IDC) connector, utilizing a “punch down” process, saves installation time by eliminating the need to fully untwist and straighten the eight conductors. However, this process does leave the connection with a slight tendency to loosen over time due to vibration. Another alternative, ruggedized RJ45 connectors, such as R301601, utilize a quick termination solution with a cable manager that frees the user from performing punch down action eight times for each termination. This method does not require any special tooling, is easier to perform and is more reliable over time compared to the IDC punch down method.

 

Of course, many installers and maintenance people avoid the need for termination onsite altogether by specifying pre-terminated cord sets—industrial Ethernet cables with the desired connector already expertly installed and overmolded at the factory. This provides “plug and play” convenience and surety, and little chance for termination damage in installation. However, it does create some additional effort in the design stage to specify the proper length of cable for each span, and for those runs with horizontal cable buried in the wall, measurement accuracy can be especially difficult.

 

When it comes to field termination, Belden has a new solution to consider—the DataTuff Industrial REVConnect system. RVAIP2SME-S1 is just one of the many configurations. These connectors (both plugs and jacks) use a universal cable manager and specialized tool that creates a reliable IPC (Insulation Piercing Contact) without separating each of the four twisted pairs, bringing termination time down to less than a minute, even for highly robust bonded pair cables. With this system, nearly anyone can quickly get good, repeatable termination results with minimal effort, with little need for long term experience and technical skill or the need to face a steep learning curve each time. For example, I personally have no field termination experience, but was able to do quality terminations using this system after just a couple of trials. No wonder reported rework rates using the Industrial REVConnect system are about 1%!