unprotected low v direct burial splices
BruceT999
| Posted in Energy, Heating & Insulation on
I fixed a low voltage garden light for a HO today and found that the original installer had stripped about an inch of the direct burial main wire, twisted the branch wire to it and buried the whole mess.
Why does the system still work? It would seem to me that every such splice in the system is a direct short to wet ground.
BruceT
Replies
Earth is a very poor conductor. The splice, when the ground is wet, is likely drawing the eqivalent of one or two path lights, but that's not enough to cause a noticeable difference in most cases.
Water is also a poor conductor. It is the impurities in the water that make it conduct.
As a kid, I remember an experiment where water was used in between two conductors to light a bulb. At first it didn't light. They kept adding salt and all of a sudden, we all saw the light.
Ed
The other are right about the ground conducting!
The cheap kits come with an insulation piercing quick connector.
But there is another problem that needs to be address. Moisture will get into the connections and corrode them.
I like to use the "silicone grease" filled wire nuts. King is one brand and they have them at Lowes.
Yeah, corrosion is the biggest problem in this situation. Coating the connections with silicone grease (which won't absorb moisture like petrolatum contact grease) and encapsulating them somehow (at least tightly taped) will go a long way to ensuring reliable operation (and will reduce current drain as well).
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
I did a repair on some landscaping lights that had a better deal than the grease filled wire nuts.They more of a potting cup. A rubber resivor full of "grease" along with a rubber cap and flaps where the wires could go through.Used a plain wire nut and then snaped the cover over it. I have not tried to find them as I only do one or two at a time.But this was a good high end job. But they would never return to fix the small problems.
Thanks guys, for the explanations.I used direct burial wire nuts for my connections, but I wasn't about to start messing with all the existing connections.BruceT
Low voltage shorts are interesting when the transformers overheat protection fails.
Been there... done that... got the charred remains to prove it.
For reasons I will never understand people treat low voltage like it's harmless....