RESIDENTIAL BY DAVID SHAPIRO
Before I arrived on the job, I knew
there were unsafe connections. The new
homeowner had shared an inspection
report that listed air splices (open splices)
in the attic. I also knew that the panelboard was poorly labeled. I anticipated
carefully labeling the circuits with help.
I also thought about how I would identify the circuit feeding the open splice so
I could safely de-energize it.
It was simple: if I could get a reading without getting my fingers on the
wires or connectors, the homeowner
and I would find the circuit. We used
a simple divide-and-conquer approach
for circuit identification to narrow down
the source of power to any location without guesswork. (I include the use of my
electronic circuit tracer in the category
of guesswork.) For divide and conquer,
though, I need a signal to check. I’m not
sure how far to trust a glow tester, so
my fail-safe is the wiggy. However, this
requires direct contact.
I’m not going to wrestle with dangerous wiring to get a good signal, but
sometimes I can insert the tip of a probe
inside a wirenut and make good contact.
If that isn’t an option, I would simply kill
all power to the house. With even the
worst wiring touch-safe, I could then
open connections and redo them so I
could test safely. But would I need to go
through all this?
First, I had to get to the offender. The
air splices were tucked under the eaves, in
an area with nothing but roof joists, ceiling joists and loose-fill insulation. From
what I could see, someone had taken two
BX (AC) cables and added Romex (NM)—
probably a switch leg—to their connection.
Not using a box meant that the installer
had eliminated proper grounding.
I pulled some plywood forward along
the ceiling joists so I could crawl to where
I had nothing but two-bys to support
me. Then I carefully inched closer and
reached over with my wiggy; it looked like
I could insinuate it under the skirts of the
wirenuts. Very carefully, obviously.
Suddenly, an arc! No spattering
metal, no shock, but woof! I still don’t
know what happened for sure. I think
that I disturbed the upstream cable’s
once-black conductor, and damaged
insulation allowed it to short to the
It doesn’t matter, though. I went
downstairs and took a breather. The
circuit breaker had tripped, killing
power to most of the upstairs lights and
assorted receptacles. This—I’ll state just
in case some reader doesn’t know better—is not the recommended method
for identifying the overcurrent device
When I went back up to the eaves, I
was determined to remove the hazard
and leave my customers with a working system. I’ll point out that I wasn’t
making it fully right because it was clear
that someone had mucked around with
the wiring. Whatever I did in the eaves
would leave untouched the other end of
an illegally run cable, installed by someone ignorant of or indifferent to the ideas
of enclosure and grounding. Still, the idea
of splices lurking—waiting for the merest
touch to arc—meant they could so easily have caused a glowing fault. I vowed
that they would be safe before I left. My
customers were a very nice older couple,
and they were really looking forward to
moving into this house.
Of course, I made it safe. I crawled
back into the eaves and mounted a
suitably sized junction box on a roof
joist. I cut back the armor on the BX to
where the rag insulation was reasonably
acceptable, brought the cables into the
box through suitable connectors, and
stapled them to each side. I brought the
Romex in through a Romex connector
and stapled and bonded it to the box. I
then identified the switch leg, upstream
conductor, hot, and neutral and spliced
them accordingly. I attached the appro-
priate cover and labeled it with the
All better? Hardly. Yes, I had taken a
good swat at protecting my customers.
But I had taken a chance, first off, and
I had been hard on my body, second.
Neither was necessary. Most important,
my determination to make it functional
and safe before I left meant I had signed
a blank check against my personal
resources. Safety usually can be accomplished by killing power to a mess if it
contains more than can be resolved in
one day. And that’s reasonable.
A Dangerous Mess
The job isn’t done until everything is safe
I WAS NOT SHOCKED, nor was I injured in any way, when an illegal connection
arced. But the experience staggered me. After I caught my breath, I responded with
anger and determination: Before leaving, I would make this safe.
SHAPIRO, author of “Old Electrical Wiring: Evaluating, Repairing, and Upgrading Dated
Systems,” is a contractor, consultant, inspector and writer/editor based in Colmar Manor, Md. He
also is affiliated with IAEI. He can be reached at email@example.com. T H