CD1410TechnologyWiringJR
CD1410TechnologyWiringJR
CD1410TechnologyWiringJR
CD1410TechnologyWiringJR
CD1410TechnologyWiringJR

Poke-to-Terminate Technology Could Simplify Your Wiring Plans

Oct. 17, 2014
Don't Underestimate the Usefulness of These Workhorse Connectors
About the Author

John Rezabek is a process control specialist for ISP Corp. in Lima, Ohio.

The garage door opener: what an enduring automation achievement. It's control over wireless, right? Modern ones are "multivariable," and you can employ bring your own device (BYOD), controlling actuator, lighting and locks from a smartphone. But aside from the phone, this application has been around for decades. Wireless automation has been commonplace for generations.

Mine stopped mid-lift one day, and it appeared the lights all went out at the same instant. It sure looked like a breaker tripped. But a Volt meter revealed every breaker was passing power, so, even if the scribbled circuit labels were wrong, power should be present at all the fixtures. It wasn't until after a couple days of manual garage-door rassling that the real culprit emerged: a bad outlet. The 40-year-old outlet had ceased passing power to daisy-chained fixtures downstream, including the garage door opener and lights.

Also Read: It Always Takes Connections

The outlet employed another decades-old technology—poke-to-terminate back-stab connections. If you've ever done any household wiring, perhaps you've been intrigued by these handy mechanisms, a hole where you can insert a stripped solid conductor of the proper gauge. Once you poke it in, you're done—it isn't coming out. It's important to use only the proper gauge, such as 14 AWG and only solid wire. If you ever need to remove the conductor, there's (sometimes) a spot for a screwdriver blade that presumably will free the wire. In my case, Mongo (me) had to smash the receptacle to get the old conductors out. New receptacle installed—automation restored! But, I didn't use the poke-to-terminate holes; instead I used the even-older-school screw connections. Sweating in tight spaces and with College Gameday beckoning, why not use the quick and easy method? After all, it took nearly 40 years for the original receptacle to fail—that's not a horrible MTBF.

[pullquote]Try posing the question to a journeyman electrician or your favorite (successful) handy man and you're likely to be admonished like it was inscribed on stone tablets: never, ever use the back-stab spring-clamp terminations. It seems these guys and gals have been on many a call where, like me, a fault was traced to the cheap and expedient wiring method.

The sullied reputation of the cheap household wall outlet, unfortunately, colors our perception of precision-manufactured terminations designed for industrial networks. Many of us operate in a harsh climate (ours is cold), and we're on the lookout for technologies that will improve the speed and accuracy of craftspeople who have to function in it. Tubular-clamp screw terminal blocks have been a mainstay for decades, and making such terminations is an expected skill for most experienced electricians. But the task invariably requires hours of gloves-off work in a fixed location, where inclement conditions take their toll on productivity. What if you could make wiring faster and easier without compromising signal integrity and long-term reliability?

Highly engineered push-to-terminate technology has been around for more than 10 years, and its ancestor, the spring-clamp terminal block, even longer. We've grown accustomed to seeing spring-clamp terminals appear on compressor skids where high vibration is the norm, so why do they get the kibosh for a less stressed application? The newer poke-to-terminate varieties are available from all of our favorite terminal block suppliers, and there are millions if not billions deployed in numerous industries. The current offerings accommodate wire gauges down to 26 AWG, and many will accept a stranded wire without a crimp-on ferrule. There are flavors that are a one-shot deal—once the wire is inserted, it's not coming out without breaking the terminal. Maybe that's what you want for hazardous areas where arcing and sparking is a concern. You can get some that release with a small flat-blade screwdriver, and there are varieties that have built-in levers or pushbuttons for releasing the conductor. Look for terminals that are constructed with substantial barriers between terminations and conical holes for funneling one or more conductors into the clamp. The "cone" also helps keep stray strands from contacting other conductors.

Curmudgeonly electricians may still insist on screw terminals for residential power, but, if you want your people to consider poke-to-terminate technology, it's easy to get samples from the factory or a distributor. We don't have 40 years to "test" the technology, so try them in your least-forgiving environment and see how they compare.