John Rezabek is a process control specialist for ISP Corp. in Lima, Ohio. Email him at [email protected] or check out his Google+ profile.
Present-day engineers have a lot of excellent technology at their disposal. In many cases, the complexities of an application can be reduced through software "wizards" or pre-packaged scripts. But, for much of our systems to function, we still depend on reliable connection of copper conductor to copper conductor, and for those connections to be both secure and accurate. No amount of wizardry can overcome issues arising from an incorrect or intermittent electrical connection.
SEE ALSO: Five Common Problems With Wiring and Connections
Okay, I guess a network wizard might suggest something like "check electrical connection," but it offers little help to get it right the first time. Making reliable terminations still requires craftsmanship and care in the actual (as opposed to virtual) world.
Terminations need to be made reliably under all manner of adversity. Standing still for an hour or more in front of a field junction box, an electrician's hands might not be the steadiest. Maybe it's not just the cold — the Stanley Cup playoffs went to three overtimes last night, so it could have been an especially early morning at the hotel or campsite. Repeatedly stripping jackets, shields and insulation from conductors, properly shortening signal and drain wires, applying heat shrink, affixing a ferrule, and landing on the correct one of hundreds of densely-packed terminals can be a significant challenge even when we're free of affliction, environmental or otherwise.
The first step to get a pair of wires landed properly is to remove the jacket. Foregoing metal armored cable for the moment, the risk in improperly removing the PVC or polymer jacket is to nick or even sever one of the contained conductors. If your electricians still use a pocket knife or utility knife, there might be some relatively inexpensive tools that can improve their accuracy and productivity.
Most of the all-in-one tools for crimping RJ45 (Ethernet) jacks have an appliance for measuring and removing the proper length of insulation, but I've used them with mixed results, i.e., I still end up cutting or nicking some of the contained conductors. It might be worth investing in a tool that's specifically for jacket removal. Searching the Internet, you can find capable offerings from manufacturers such as Wiha and Xcelite that can be adjusted precisely for a specific cable thickness, which is useful if you're landing many pairs of the same specification.
For the conductors, there's another cadre of capable specialty tools for stripping signal-gauge (16 to 24 AWG) pairs for termination, again without nicking any of the strands. The self-adjusting variety of wire strippers have the potential to increase efficiency and minimize errors and rework.
Now that you've invested maybe $200 per electrician, aiming for more reliable and consistent wire preparation, what do you do with the neatly stripped ends? If you're using a cage-clamp block like those made for many years by Wago, you might think you're done. But even with spring-clamps, strands can get splayed and cause short circuits or intermittent connections to adjacent terminals, as well as weaken the termination you aimed to make. The preemptive solution for preventing the scourge of the stray strands is the "shoelace" ferrule. Its function is very similar to the aglets on shoelaces — they keep unruly strands together. While crimping a ferrule on each conductor adds time to the job, and creates another opportunity for quality and craftsmanship missteps, most believers use them religiously. You can argue that the problems avoided by more consistent and precise terminations far outnumber those that arise from an errant crimp job. A little training, the right crimping tool, and using the proper gauge ferrule for the conductor should keep crimping problems to a minimum. And if you're using screw terminals, most of the experienced installers I know highly recommend tightening to spec with a torque screwdriver.
What about after the cable's pulled, and the backhoe chops it in two, hundreds of feet away? Before you pull in all new wire, you might be able to recover more quickly with a "Quickon" splicing connector from Phoenix Contact. It's bigger and more expensive than a butt splice, but when installed according to the instructions, it provides an IP68 high-integrity repair. While it looks and feels like a robust solution, users should check its suitability for the particular area and hazard rating.
While we can't click a wizard to simplify terminations, we can take some steps to improve the efficiency, accuracy, and overall quality of our termination jobs. And you might even notice that your small investment pays dividends in the care and pride of the workforce.
