solder pot

November 17, 2023 Image

Article 10 – Connections To Extend or Repair A Fixture or Home Run Cable

Inline Connections

A quick, inexpensive yet durable method for making an outdoor wiring connection.

The Problem – Fixture Cable Needs to Be Longer

So you are using the hub method of wiring and not all of the fixtures in the design you are installing have lead cables long enough to reach the intended hub location. So, one or more fixture lead cables will not reach the intended hub location. You could extend the Home Run (HR) cable and add another hub location. But what if it is a fixture that is rain gutter mounted to illuminate a dormer, second story gable or attractive chimney and the fixture cable only reaches to somewhere in the middle of the downspout? I’ll describe a method of creating a robust (electrically, physically and hermetically) connection in this article.

A quick and inexpensive way to make a solid electrical connection is to use a corrosion resistant non-insulated “Butt Splice”. These connectors that allow the 2 ends of the connecting wires to “butt” up against each other are also known as “Barrel Connectors” or “Butt Crimps”. The insulated version for hobbyists and technicians doing repairs in protected areas are very common. When performing a connection that will be in the earth or exposed to water it is important that the connection be corrosion resistant, well protected from moisture and not easily separated if the cable gets snagged whilst someone is working nearby.

A Brass Butt Crimp Type Connector With a Tin Coating for Corrosion Resistance

The description I am provided is detailed and a bit lengthy but the actual process is quite quick for someone who has made a few of these simple connections. You may jump to the video at the end of the article if you want a quick visual summary.

What will I need?

The tools you will need are a wire stripper, proper crimper and a heat gun. (A separate post will be made for Tools use for low voltage lighting)

Examples of 2 Types of Crimpers – Note the One on the Right is
Favored as it Accepts Two Sizes of Crimps

The supplies you will need are the proper size butt crimps, proper size double layer heat shrink and UV resistant nylon wire ties.

The marked and unmarked wires are separated and the ends stripped of insulation in preparation for connecting. Only strip enough to allow the wire ends to reach the mid point wire stop in the butt crimp.

Slide the shrink tubing over one end of each of the wires. If you forget to do this, you will have extra practice stripping and crimping. 🙂

Carefully slide the butt crimp over one stripped wire and crimp the connector with the crimper center between the mid point wire stop and the end of the butt crimp. Repeat this for the connecting wire.

The butt crimps are available in different sizes to accommodate various ranges of wire sizes. The same for the heat shrink tubing. In this example the wire is 16 AWG No-Ox Low Voltage Landscape Lighting wire and the splice is an Ideal #14-#16 size. The heat shrink tubing is a 3/16″ ID size.

Slide the shrink tubing over the crimped connection and center with the butt crimp. Using a heat gun begin heating the shrink tubing starting at one end and working towards the opposite. Provide heat around all sides of the shrink tubing. There is an adapter for many heat guns that distributes the heat around the wire more uniformly than an open ended one like I use. (I’ll add details about this in the Tools post that is forthcoming)

More on Connections

In a separate post I will cover other types of connections such as connecting to an existing hub circuit and making a repair to a damaged cable.

Alternative ways to connect two wires together. (Forthcoming)

Some of the Tools of the trade.

October 24, 2023 Image

Article 9 – Hub Connections In Low Voltage Landscape Lighting

Hub Connections

Make the Connections

I feel the best way to assure a solid and durable electrical connection is to solder the connection. The most efficient way to do this is to use a solder pot. Trust me, I have tried other methods such as a micro torch and a high output soldering gun. They are SLOW and cause minor degradation of the insulation. Once the connection is soldered it is covered with a dielectric grease filled, direct burial wire nut. The wire nut does not serve to hold the conductors together, that is done by the solder. But, it prevents the conductors from creating a short circuit by directly touching another conductor or contacting a conducting surface. Plus, the dielectric grease seals the end of the wire to prevent wicking of moisture into the stranded wire causing a slow degradation of the conductors.

Here’s the steps I follow. They may be confusing but the pictures and short video may prove helpful.

If the HR cable is looped at this point, cut it at the loop to create two ends. Separate the 2 wires of all cables (HRs and fixture) to about 10″. Strip the ends of all the MARKED wires back 1-1/4″. Place a wire tie snuggly around this bundle of wires. Repeat the stripping and bundling for the UNMARKED wires. Focusing on one bundle at a time, carefully align the insulation ends of each wire in the bundle. Once these are aligned, carefully and firmly twist the conductors together. Snug the wire tie to help limit movement of the prepared bundle. I place a length of stretchy electrical tape snuggly around the bundle at less than 1″ from the ends. The tape acts like a sticky rubber band to hold the stripped ends in alignment and prevents the twisted conductors from unraveling. Repeat this for the second bundle. Additionally, you may place a standard, indoor type of wire nut on each twisted group to temporarily hold the conductors together.

Showing how separated marked and unmarked wires are bundled in preparation to soldering the connections.
Marked and Unmarked Wires are Separated and
Bundled in Preparation for Soldering
Two HR Cables and Four Fixture Cables in This
Prepared (for testing and soldering) Bundle

This process is repeated for each location of a hub. Once all hub location wiring connections are prepared, the system may be tested by connecting the HR(s) to the transformer and applying power. Once all the fixtures are verified to be functioning, the power may be removed and the connections soldered.

Soldering is a very quick process once the solder pot is up to temperature. I recommend preheating the solder pot for 30 minutes before you are ready to begin soldering. Cold, windy weather conditions will require even longer preheat times.

The soldering process is simple but respect for the fact the metal is molten (very hot) is very important. Wearing safety glasses and gloves is recommended. Different types of solder may be used. The most common is 60/40 lead/tin (60% lead & 40% tin) so understanding the importance of using heated lead in a ventilated area is important. Even more important is to not allow the lead to get in your mouth. Sounds like a strange thing to say but lead on your hands can find it’s way into your mouth if you grab a sandwich after handling lead without washing your hands, for instance. Flux is also a material you want to keep out of your body along with the fumes it generates when heated. So use sensible practices and read up on these two materials.

The flux is applied to the ends of the bundled conductors about half the size of a BB by dipping the conductors into the flux. With the solder pot very close to the bundle, insert the fluxed conductor bundle straight down into the center of the molten solder up to the insulation but not touching the insulation. As the conductors reach temperature you will notice that the solder intimately contacts the conductors and begins to wick up the strands. The video below demonstrates this process.

By cutting into a soldered connection it is visible how solid this connection actually is.

Dissected Soldered Hub Connection

If a system is expected to be expanded at a later date a 12 – 18″ length of HR cable may be soldered into the bundle and capped for later use.

The hub method reduces the number of connections to the HR cable which saves installation time and soldering at the connections greatly improves reliability of the wiring system.

More on Connections

In a separate post I will cover other types of connections such as extending a fixture cable, connecting to an existing hub circuit and making a repair to a damaged cable. (Forthcoming)