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Although the ideal situation would be to have complete conductor runs with no splices, it's not always possible. When trouble shooting or adding another run to branch off the original, you'll need to use a secure way to terminate any splices to avoid loose conductors.

Secure Wire Termination Options

Steve Maurer, IME
Although the ideal situation would be to have complete conductor runs with no splices, it's not always possible. When trouble shooting or adding another run to branch off the original, you'll need to use a secure way to terminate any splices to avoid loose conductors.

When installing some equipment, you must securely connect the equipment leads to the incoming wiring. Back in the day, many splices were made by soldering the conductors together, then covering the splice with a good wrap of electrical tape. And many old-time electricians still favor this method. Done properly, it does create a secure connection.

But it is time-consuming, to say the least. When major projects come up with a large number of splices to be made, quick but secure methods of wire termination are used. Remember to always check with national and local codes before selecting the termination method you'll use. Even some companies have standards you'll need to adhere to when performing electrical work in their facilities.

Wire nuts – the old workhorse of wire termination
Everyone's familiar with wire nuts, even home do-it-yourselfers. If you're like me, you likely have a jar on the kitchen counter full of them. Left over from wiring jobs, they travel home in my pocket and end up on a tray or in a jar, waiting to be pocketed again when I leave for the next job.

They're usually color-coded for the size wire they're designed for. If you've used them long enough, choosing the correct one is fairly intuitive. But nothing irks me like a newbie using too large a wire nut for an application. I see this the most when a worker is wiring up a motor and uses too large a wire nut for the leads that connect internal windings on a three-phase motor.

My personal preference is to use wire nuts with 'wings' that allow for a more secure grip when installing. There are even tools available to use to spin on the nut. Just be sure not to over tighten and break the conductors.

There are some wire nuts designed for direct burial applications, such as low voltage outdoor lighting. They'll have some sort of sealant inside, usually silicon-based, and have external flaps to help seal them. Remember that the silicon sealant may be removed during rewiring. Be sure to use a new connector if replacing or re-splicing.

Push-in style connectors speed up installations
These connectors quickly became my favorite for lighting retrofits, although they're good for other applications. With the number of ports ranging from two to eight, these push-in style connectors make quick work of splices and component installation. One conductor is pushed into each port.

While they can be used with stranded wire, they work best with solid conductors. Because they work by using a blade that secures the wires in place, there are some stranded conductors that aren't stiff enough to secure properly.

But for installing ballasts and LED drivers, they're hard to beat. I've been retrofitting a lot of fluorescent fixtures with LED tubes and belly plates. These connectors speed up the process significantly, allowing for more fixture to be completed in a shorter time period.

Made of a clear polycarbonate shell and a color coded insert, it's easy to determine if the conductors are properly seated with just a glance. They can be used for both building wiring (with some limitations) and fixture wiring.

I love them so much … I buy them by the "jug."

Set screw connectors
For larger conductors, a set screw connector might be a better option. Normally available for two and three conductors (with some manufactures offering more options), they mechanically bond the conductors together.

These days, many come with a neoprene or plastic coating, they pretty much eliminate the need for taping the connection. Most are rated for use with a combination of aluminum and copper conductors.

They are available for voltages up to 300 VAC with a snapping cover, while others are rated for higher voltages found in industrial settings for motors and such. They usually come with a dab of corrosion inhibitor in the fitting, which will need replaced if reused.

I started using this type of connector years ago for motors with horsepower ratings above 50 HP. While they don't require taping, I'm a little old school and do apply one or two wraps to ensure things stay in place. A little precaution never hurts.

Specialty connectors
Although I haven't done a lot of direct burial work, there are specialty connectors designed for this application. Used a lot in irrigation, outdoor lighting, and pump house applications, these are mostly for low voltage use.

I've seen a lot of them with clear shrink tubing or see-through housings that allow for quick inspection of the connection to check for corrosion and degradation.

Whatever you use in whatever application you have, make sure to check to ensure they have the proper standards approval and follow all local and national electrical codes.
Photo courtesy of King Innovation
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