Weather Proof Connectors For Low Voltage Wiring

Updated on December 15, 2017

In the beginning.

I started wiring at 16 on old cars I owned. The wiring was a mess on many of them and I had to figure out how to get them running. Doing wiring repairs I would go to the auto parts store and pick up whatever connectors were inexpensive (ie: cheap).  After some time and trial and error,  I  learned a valuable lesson about weatherproof connector quality.

Why Does Using The Right  Weatherproof Connector Matter?

As I said; when I started out using crimp connectors I would use just anything that was cheap and that I had the tools for, usually pliers. I would sometimes spend days figuring out the problem and then repair the wiring with the cheap connectors and tools. A few months later especially after going through a rough Colorado winter, I found I had shorts or dead wires in the system and would have to go back over everything again to re-fix the issue. Often times, the issue was at the connector I had used for the repair. The inexpensive crimp connector would have consistently allowed moisture and dirt into the connector and the result would be corrosion and a failed connection. After having this come up several times, I got to thinking there has to be a better way. After checking around with more experienced automotive technicians, I found there was a big difference in the quality of electrical connectors for low voltage, (basically 12 or 24 volts) wiring connectors. Also, there were connectors available that were water / Weatherproof. Of course, they were there all the time I just didn’t think I needed them.

Using Good Weather Proof Connectors Makes Sense

My problem was that in using inexpensive, poorly made connectors or not using the correct connector for the job, I wasn’t thinking long term. I hadn’t given much thought to corrosion and how it would affect the wiring system over time. Usually a surprisingly short time. Also such as in the case of trailer wiring, there were areas where the wiring was exposed to dirt and water. Not good for wiring or connectors! If you ever had to fix trailer wiring in the middle of the night in a snowstorm in the mountains because you had no lights, you know what I mean.
Most of the inexpensive connectors made poor connections and had very little in the way of insulation or a way to keep dirt and moisture out. After a short time, water and dirt would get inside and corrosion would result, creating a dead connection or short. Even if you wrap them in electrical tape, as I often did, the tape would come apart not holding up against the weather and eventually the connection would fail. Failure to choose connectors that weren’t meant to be exposed to the elements is asking for trouble.

Solution: Choosing The Right Connector.

There are many connector types and brands to choose from. The first thing to consider is where will the connector be used? Will it be exposed to the elements, in a dirty or greasy environment, How about heat? Some of the connectors pictured in the first two illustrations would be fine in a dry environment away for contaminants, but to have a quality long lasting weather, grease, dirt proof connection, I would recommend using something like the connectors in the third picture. My favorite for general use, NSPA Krimpa seal ® heat shrink waterproof, weatherproof connectors, shown below.

These wire connectors are either crimped on the wire or the connector itself is closed on the wire (scotchlok) Great for general purpose in dry conditions where corrosion is not a consideration.

 scotchlok  connectors                                                             3M Nylon3M Nylon Terminals

NSPS Krimpa-seal  Waterproof Connectors                       For a weatherproof seal just Crimp the terminal, then apply heat.

These are very special connectors and in my view are the best for strong reliable weatherproof connections. They have several great features.(see photos) They are both crimped and soldered. In other words, you insert the wires, crimp them with a good crimp tool, then heat them to melt the solder and heat shrink the insulation around them. At the same time, adhesive seals the ends making a strong bond that will not pull apart. This will not allow water or dirt into the connection. That results in a dependable weatherproof connection that will last.

Oh yes, there is another great feature.

There is a clear window in the connector insulation. You can see that the wires are properly inserted, crimped and solder sealed. A window allows certainty wires are in the connector before you actually crimp or heat seal the connection.
A truly environmentally sealed connector.

There are of course many  connectors to choose from

There are as many connector types as there are applications. stocks connectors for all your needs. In the next post we will go over some of these and their uses