I have low voltage landscape lights in my yard. There was a break in a long
run. I spliced it together and covered it with vinyl electrical tape. A
few days later, it looked like it had coroded or burned through at the
splice. The wire fused ends were covered with green corrosion. This has
happened twice at the same spot. Any suggestions as to why this is
happening and what to do about it?

Gypsy Moth wrote:
I have low voltage landscape lights in my yard. There was a break in a long
run. I spliced it together and covered it with vinyl electrical tape. A
few days later, it looked like it had coroded or burned through at the
splice. The wire fused ends were covered with green corrosion. This has
happened twice at the same spot. Any suggestions as to why this is
happening and what to do about it?


All moist soil is going to be conductive, yours may be more so than is
typical. Heavy fertilizer application?

Also, under the assumption that you have a step down isolating
transformer that provides the low voltage I'd check to make sure that
one side of your low voltage lighting circuit is grounded. It is
undesirable and unsafe if the secondary winding is floating w/r to ground.

Vinyl tape is inadequate for buried applications. There are crimp
connectors available that are made for wet, or buried applications.
They're gel filled and will usually resist the intrusion of water.

On Apr 5, 2:16*pm, Boden wrote:
Gypsy Moth wrote:
I have low voltage landscape lights in my yard. *There was a break in a long
run. *I spliced it together and covered it with vinyl electrical tape. *A
few days later, it looked like it had coroded or burned through at the
splice. *The wire fused ends were covered with green corrosion. *This has
happened twice at the same spot. *Any suggestions as to why this is
happening and what to do about it?

All moist soil is going to be conductive, yours may be more so than is
typical. *Heavy fertilizer application?

Also, under the assumption that you have a step down isolating
transformer that provides the low voltage I'd check to make sure that
one side of your low voltage lighting circuit is grounded. *It is
undesirable and unsafe if the secondary winding is floating w/r to ground.

Vinyl tape is inadequate for buried applications. *There are crimp
connectors available that are made for wet, or buried applications.
They're gel filled and will usually resist the intrusion of water.

The idea of covering a join with vinyl electricacl tape and burying it
in soil seems bizarre/absurd!
Surely not so?
If a splce, to be buried, is attempted at all, soldered wires and gel
filled heat shrink tubing over each wire and then additional double
layers over the entire splice could be attempted and might last a
while?

terry wrote:
....

If a splce, to be buried, is attempted at all, soldered wires and gel
filled heat shrink tubing over each wire and then additional double
layers over the entire splice could be attempted and might last a
while?

The made-for-purpose underground filled wire nuts do just fine--I've a
several-year (at least four, possibly as much as 5 or maybe even 6???
--daxx I can't recall much any more ) repair of the 240V feed to the
well pump.

I've come across repairs Dad (or maybe even Grandpa) made that have to
be a minimum of 30 or so that were still fine w/ nothing but twisted
connections covered w/ friction tape and then vinyl tape.

So, a good job w/ a _quality_ tape will last quite some time. The key
is enough layers done tightly enough and cleanly enough.

--

dpb wrote:
terry wrote:
...

If a splce, to be buried, is attempted at all, soldered wires and gel
filled heat shrink tubing over each wire and then additional double
layers over the entire splice could be attempted and might last a
while?


The made-for-purpose underground filled wire nuts do just fine--I've a
several-year (at least four, possibly as much as 5 or maybe even 6???
--daxx I can't recall much any more ) repair of the 240V feed to the
well pump.

I've come across repairs Dad (or maybe even Grandpa) made that have to
be a minimum of 30 or so that were still fine w/ nothing but twisted
connections covered w/ friction tape and then vinyl tape.

I don't disbelieve that, but why did they use friction tape UNDER vinyl
tape? The original purpose of friction tape was to protect the old
stretchable rubber tape used on such splices from abrasion. Hence its name.


So, a good job w/ a _quality_ tape will last quite some time. The key
is enough layers done tightly enough and cleanly enough.

--


Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.98*10^14 fathoms per fortnight.

Jeff Wisnia wrote:
dpb wrote:
terry wrote:
...

If a splce, to be buried, is attempted at all, soldered wires and gel
filled heat shrink tubing over each wire and then additional double
layers over the entire splice could be attempted and might last a
while?


The made-for-purpose underground filled wire nuts do just fine--I've a
several-year (at least four, possibly as much as 5 or maybe even 6???
--daxx I can't recall much any more ) repair of the 240V feed to
the well pump.

I've come across repairs Dad (or maybe even Grandpa) made that have to
be a minimum of 30 or so that were still fine w/ nothing but twisted
connections covered w/ friction tape and then vinyl tape.

I don't disbelieve that, but why did they use friction tape UNDER vinyl
tape? The original purpose of friction tape was to protect the old
stretchable rubber tape used on such splices from abrasion. Hence its name.
....

You'd have had to ask Dad why--at least partly "because Grandpa did it
that way" undoubtedly would have been a factor no doubt....

My best guess would be it was one of two reasons (altho this is purely
conjecture based on what I know of how Dad tended to think and work)...

First guess would be the idea would be the friction tape would still
serve the purpose of making sure the wire didn't cut the tape...

Second would be these were in a time when I suspect the vinyl tape was
still a new idea so it wasn't yet a comfortable thought to give it up
entirely.

In fact, a couple of these were bound to have been the original when the
lines were first laid which would go back to the early 50s -- I
uncovered them when repairing a water line leak in the same trench, not
because the wiring had a problem.

We got REC power in '48 and then is when the original wiring to the
outbuildings other than a single lighting circuit to the barn from
before when were still on the Delco system. It didn't have enough
capacity for more than the house(s) and the lights in the barn.

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