Personal experience has taught me many times that a poorly made wire splice is a costly problem. Even well made splices can go bad which only highlights the need to do wire splices right the first time. Certainly you know this too.
Since in-ground wire splices are made for landscape irrigation and lighting systems, and even in a water features, it’s worth knowing and teaching others how to do them right.
Avoid Water Problems
The most important step is to use a good WATERPROOF wire connector. Not all connectors sold for in-ground use are truly waterproof. Some are just water resistant.
Bad splices are rarely caused by the wires not making contact or pulling out of the connector. Yes that happens, but the more common issue is corrosion of the wire leads because of water vapor. Unless the connector is waterproof, moisture will get to the bare copper and cause corrosion.
The Influence of Corrosion
Corrosion acts like an insulator. As it builds up the resistance between the wires increases causing more voltage drop. Eventually the voltage drop becomes bad enough that either the device (solenoid, lamps, etc) cannot receive enough voltage to operate correctly or no current passes through the connection at all.
As resistance and voltage loss increases the amp flow has to go up as well to maintain the wattage necessary for the device. Now you get other problems, like solenoids that burn out, failed chips in controllers, and lamps that burn prematurely. Higher amperage means more heat and more failures.
Additionally, a bad splice can allow water to “wick” between the wire and insulation. I have seen wicking in my own landscape lighting system that ran over 100’. The corrosion that forms between the strands of lighting wire can cause severe voltage loss and the only way to fix it is to replace the wire.
Corrosion is especially problematic in DC systems, such as battery irrigation controllers and decoder systems. Copper will corrode quickly with DC power which causes latching solenoids not to function or the communication signal in a decoder system to fail.
An Example
A large zoo in our area had so many problems with wire splices that they spent an entire summer hunting down and replacing every wire splice on all their landscape irrigation systems. It was costly and a big pain, but the manager felt it was well worth the expense.
Teach anyone in your organization that will make wire splices how to do them right!
