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Accidentally drilled live wire.

C

Chris

Jan 1, 1970
0
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket. (I happened to hit it
right where it was stapled to the stud, so the sheathing didn't move
and I drilled right into it. Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up). Weird thing is that it cut the power to my daughter's
room, which is next door and on the same circuit as the room as I was
in, but it didn't cut the power to the room I was actually in, nor did
it blow the breaker.

Anyhow, I cut into the wall, found the damage, removed a section (3
inches?) of the metal sheathing, and spliced a piece of romex into the
line. Functionally, this did the trick. My question, though, is how
safe is this fix? The tie in is the same as for hard-wiring lighting
fixtures, for example, but this is a power line we're talking about.
Also, once I repair the wall, the splice will be essentially
inaccessible. Also, assuming I need to have an electrician come in to
replace the metal sheathed wire section, how big of a job would that
be? I suspect the sheathing is "stapled" every couple of feet or so.
Would he have to tear up the walls in both rooms to swap in a new wire?


I'm less concerned about the cost than the hassle, but I also don't
want to burn my house down. Any advice would be much appreciated.
Thanks.
 
T

tombiasi

Jan 1, 1970
0
Chris said:
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket. (I happened to hit it
right where it was stapled to the stud, so the sheathing didn't move
and I drilled right into it. Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up). Weird thing is that it cut the power to my daughter's
room, which is next door and on the same circuit as the room as I was
in, but it didn't cut the power to the room I was actually in, nor did
it blow the breaker.

Anyhow, I cut into the wall, found the damage, removed a section (3
inches?) of the metal sheathing, and spliced a piece of romex into the
line. Functionally, this did the trick. My question, though, is how
safe is this fix? The tie in is the same as for hard-wiring lighting
fixtures, for example, but this is a power line we're talking about.
Also, once I repair the wall, the splice will be essentially
inaccessible. Also, assuming I need to have an electrician come in to
replace the metal sheathed wire section, how big of a job would that
be? I suspect the sheathing is "stapled" every couple of feet or so.
Would he have to tear up the walls in both rooms to swap in a new wire?


I'm less concerned about the cost than the hassle, but I also don't
want to burn my house down. Any advice would be much appreciated.
Thanks.
You should not burry a splice in the wall.
The proper way is to get enough slack before and after where you cut the
wire to bring the ends out into a box.
The splice is made in a box with a cover on it.
The cover is accessible from outside the wall.
If you don't like a blank plate on your wall, run new wire, but do not
splice inside the wall.
Electrician cost will depend on how much time this will take.
I can't tell from here.
Only one side of the wall needs to be disturbed.
Tom
 
B

Bob Eld

Jan 1, 1970
0
Chris said:
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket. (I happened to hit it
right where it was stapled to the stud, so the sheathing didn't move
and I drilled right into it. Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up). Weird thing is that it cut the power to my daughter's
room, which is next door and on the same circuit as the room as I was
in, but it didn't cut the power to the room I was actually in, nor did
it blow the breaker.

Anyhow, I cut into the wall, found the damage, removed a section (3
inches?) of the metal sheathing, and spliced a piece of romex into the
line. Functionally, this did the trick. My question, though, is how
safe is this fix? The tie in is the same as for hard-wiring lighting
fixtures, for example, but this is a power line we're talking about.
Also, once I repair the wall, the splice will be essentially
inaccessible. Also, assuming I need to have an electrician come in to
replace the metal sheathed wire section, how big of a job would that
be? I suspect the sheathing is "stapled" every couple of feet or so.
Would he have to tear up the walls in both rooms to swap in a new wire?


I'm less concerned about the cost than the hassle, but I also don't
want to burn my house down. Any advice would be much appreciated.
Thanks.

In the US this "fix" probably violates the code. Splices are supposed to be
in junction boxes not unprotected in walls. The wires should be joined on
screw terminals or by use of wire nuts or crimps, but NOT soldered.

The best way to do this is to put a metal junction box in the wall where the
break is and splice the romex addition to the existing wires in the box
using wire nuts. The box should be closed with a cover plate and may be
walled up after the repair. There is no need to re-wire the whole length
with a new sheathed cable.
 
J

Jamie

Jan 1, 1970
0
Chris said:
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket. (I happened to hit it
right where it was stapled to the stud, so the sheathing didn't move
and I drilled right into it. Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up). Weird thing is that it cut the power to my daughter's
room, which is next door and on the same circuit as the room as I was
in, but it didn't cut the power to the room I was actually in, nor did
it blow the breaker.

Anyhow, I cut into the wall, found the damage, removed a section (3
inches?) of the metal sheathing, and spliced a piece of romex into the
line. Functionally, this did the trick. My question, though, is how
safe is this fix? The tie in is the same as for hard-wiring lighting
fixtures, for example, but this is a power line we're talking about.
Also, once I repair the wall, the splice will be essentially
inaccessible. Also, assuming I need to have an electrician come in to
replace the metal sheathed wire section, how big of a job would that
be? I suspect the sheathing is "stapled" every couple of feet or so.
Would he have to tear up the walls in both rooms to swap in a new wire?


I'm less concerned about the cost than the hassle, but I also don't
want to burn my house down. Any advice would be much appreciated.
Thanks.
its not up to code!
not suppose to have boxes or wire attached to the studs, they are
suppose to be 1.5 inches or more away from the studs. that is why they
made the rule in the NEC book. you use wooden stand offs or metal
brackets that can be attached to the studs if you want
different rooms are suppose to be on their own circuit for the outlets
and lights are on their own circuit etc....
 
G

George

Jan 1, 1970
0
Can you locate the place where this wire enters the wall in the attic
or basement?
if you can does it go directly from its point of entry down the wall to
a switch or outlet?
If so you could cut the wire there, pull a new section of wire down (or
up) to the switch or outlet and set a box in which to make the
connection.

I'm assuming your referring to a flexible metal conduit or sheathing
was used
I'm curious as to why someone used that in residential wiring.
 
D

DecaturTxCowboy

Jan 1, 1970
0
Chris said:
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket.
Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up).

I'm more curious why the "live wire" sensor didn't detect the wire.

Any idea how far away the wire was from the sensor? Did you move the
sensor around the spot you were going to drill with several passes with
the sensor orientated up/down and left/right?

Can you verify the sensor is working by passing it around a known live
electrical outlet?

"Annoying" is an understatement.
 
C

Chris

Jan 1, 1970
0
I moved it all over the place--and the wire couldn't have been more
than the thickness of a piece of drywall plus maybe an inch or so from
the sensor. Also, because I saw there was an outlet more or less in
line with where I wanted to drill, I did it a few times and the only
reading I got was right by the outlet itself. So I
assumed--incorrectly, obviously--that the wiring went down through the
floor instead of up the wall.
 
D

DecaturTxCowboy

Jan 1, 1970
0
Chris said:
I moved it all over the place--and the wire couldn't have been more
than the thickness of a piece of drywall plus maybe an inch or so from
the sensor. Also, because I saw there was an outlet more or less in
line with where I wanted to drill, I did it a few times and the only
reading I got was right by the outlet itself. So I
assumed--incorrectly, obviously--that the wiring went down through the
floor instead of up the wall.

Sorry...my bad. I misses the part about it being in a metal sheath. That
would explain the sensor not picking it up. It would pick it up around
the outlet as it has a plastic cover.

But I would also wonder why the metal stud detector of your stud sensor
didn't see it.

When cutting or drilling into walls, I don't like to assume there is
nothing behind them - especially with residential work. So I use my stud
sensor and Greenlee live wire sensor, followed by a magnetic stud sensor.

Now someone up with a fresh water in a PVC pipe detector - they already
have (bull)sh*t detectors for the sewage lines. <snicker>
 
J

Jasen Betts

Jan 1, 1970
0
I moved it all over the place--and the wire couldn't have been more
than the thickness of a piece of drywall plus maybe an inch or so from
the sensor. Also, because I saw there was an outlet more or less in
line with where I wanted to drill, I did it a few times and the only
reading I got was right by the outlet itself. So I
assumed--incorrectly, obviously--that the wiring went down through the
floor instead of up the wall.

it could be that your live wire detector only detects wires that aren't
encased in metal. If it has a metal detector setting that may get you
what you want.

Bye.
Jasen
 
C

Chris

Jan 1, 1970
0
DecaturTxCowboy said:
Sorry...my bad. I misses the part about it being in a metal sheath. That
would explain the sensor not picking it up. It would pick it up around
the outlet as it has a plastic cover.

But I would also wonder why the metal stud detector of your stud sensor
didn't see it.

When cutting or drilling into walls, I don't like to assume there is
nothing behind them - especially with residential work. So I use my stud
sensor and Greenlee live wire sensor, followed by a magnetic stud sensor.

Now someone up with a fresh water in a PVC pipe detector - they already
have (bull)sh*t detectors for the sewage lines. <snicker>

That would be my fault--I knew the wall had wooden studs so it never
occurred to me to flip the stud finder over to "metal" mode. Of
course, I wasn't counting on the armored electrical wiring. Live
(luckily) and learn, I guess.
 
D

DecaturTxCowboy

Jan 1, 1970
0
That would be my fault--I knew the wall had wooden studs so it never
occurred to me to flip the stud finder over to "metal" mode. Of
course, I wasn't counting on the armored electrical wiring. Live
(luckily) and learn, I guess.

<BIG SIGH OF RELIEF> at least its not a mystery now. Undetected wires
are evil.
 
A

Alan B

Jan 1, 1970
0
it could be that your live wire detector only detects wires that aren't
encased in metal. If it has a metal detector setting that may get you
what you want.

I'm betting on this explanation. The metal sheath will "suck up" any
magnetic field that the detector might be looking for. Permeability is the
magic word.
 
E

ehsjr

Jan 1, 1970
0
Chris said:
No harm done (to me, at least), but I accidentally drilled into a live,
metal sheathed wire while hanging a tv bracket. (I happened to hit it
right where it was stapled to the stud, so the sheathing didn't move
and I drilled right into it. Other annoying thing is that I actually
used a stud sensor with one of those wiring detectors, but it didn't
pick it up). Weird thing is that it cut the power to my daughter's
room, which is next door and on the same circuit as the room as I was
in, but it didn't cut the power to the room I was actually in, nor did
it blow the breaker.

Anyhow, I cut into the wall, found the damage, removed a section (3
inches?) of the metal sheathing, and spliced a piece of romex into the
line. Functionally, this did the trick. My question, though, is how
safe is this fix? The tie in is the same as for hard-wiring lighting
fixtures, for example, but this is a power line we're talking about.
Also, once I repair the wall, the splice will be essentially
inaccessible. Also, assuming I need to have an electrician come in to
replace the metal sheathed wire section, how big of a job would that
be? I suspect the sheathing is "stapled" every couple of feet or so.
Would he have to tear up the walls in both rooms to swap in a new wire?


I'm less concerned about the cost than the hassle, but I also don't
want to burn my house down. Any advice would be much appreciated.
Thanks.

It is neither safe nor up to code.
If you can get enough slack (not likely), you can
splice the wires in a new junction box at the site
of the break. The box must be accessible after the
wall is repaired. Sometimes it works well to put
a receptacle in the new box.

If you don't have enough slack, you either need
to tear into the wall (bad news) or do a bit of
rewiring. That means disconnecting the cable
at the last outlet before the break so that the
section of wire in the wall is dead, and running
a new cable from the basement or attic to the
first dead outlet that died as a result of the
drilling.

Since you are less concerned with the cost than the
hassle, hire an electrician. They are good at this
kind of repair with minimal disruption.

Ed
 
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