paranoid electrical question

[rieferman]

So, the walls are all closed in around the new wiring by now (although the wires won't be live until this weekend)..

I was installing a loft-style shelf the other day, and one nail fire from the nail gun sparked back at me - this normally only happens to me if I'm firing into old barn wood and hit some embedded something or other, or when the old sleeve of nails ends and the new sleeve begins. The nail *did* sink all the way properly. This was a new stud that was being nailed into (through OSB covering though).

But, since then, I've been paranoid that the spark was the nail hitting something behind the OSB. Like a staple holding the new wiring in place. Or the wire itself. I know it didn't hit a box because I can walk around to the other side and look into the boxes for my recepticals.

So my question is:

Do you think I really hit something, or am I being paranoid (i.e. how unlikely is it to fire a perfect shot right into electrical wiring such that it would puncture the wire)?

And,

Is it something we can somehow test for to prove it once and for all? How?

 

[travisd]

If things aren't live yet, a simple Ohm meter will tell you if you have a short or not. Check all the possible pairs to see if there's any continuity. If you know what circuit is there you could also try checking for continuity between the Nail and the conductors.

 

[rieferman]

ahhh, sigh of relief. There's no power in there yet (electrician is coming Sunday to wire the box and make final connections) so it sounds like I can explain my fear and he'll be able to test before hand pretty easily.

Considering your speed to respond, it sounds like many a person has worried about similar types of issues since the dawn of time

Thanks for your response!

 

[Gary S]

A nail shouldn't spark on copper wire with no power to it.

Yes, it is possible and actually quite common to drive a nail into a wire and either short the wires together, or hit the hot lead of the wire so the nail becomes a hot conductor and also an electrical leak that can be a fire hazard. A couple of years after I bought my house, I decided to do some work in my basement. I lifted out some of the suspended ceiling panels to work, and when my drill bumped the ceiling grid, it drew a big electric spark and ate a chunk out of my drill bit. I checked the ceiling grid only to find that it had around 85 volts on it. Apparently whoever installed the grid accidently drove one of the nails into a hot wire in the wall somewhere. I took the easy way out and instead of pulling the ceiling grid wires to find the offending one, I cut loose the wire from the shorted circuit and put in new wiring to replace it.

 

[tcianci]

Even if you were to hit an energized wire with a nail gun, if the wire were buried behind wood, you would not see a spark, you would only create a spark if you had provided a path for current to flow through and that is impossible with an nail gun that is not grounded.

 

[walrus]

Even if you were to hit an energized wire with a nail gun, if the wire were buried behind wood, you would not see a spark, you would only create a spark if you had provided a path for current to flow through and that is impossible with an nail gun that is not grounded.

Its not impossible, unlikely maybe

 

[rieferman]

Good news guys, didnt hit a wire afterall, everything is up and running (soooooo glad to have power again! nothing like having an outlet every few feet, up on the ceiling, around every corner...)

 

[independentrider]

when you get power to it if the nail hit it it will immediately trip the breaker

 

[sharpshooter63]

Did your nailer double fire? With some framing nailers that don't have single shot mode, a double fire is common, and that can cause a good spark.

 

[rieferman]

In the end, I think it was either a slight misfire of the gun (btw, I really have loved the porter cable framer that I have... It hasn't jammed once since I owned it, and I'm nearly through the entire big box of nails now) or I may have hit a another nail that was already toenailed in. It's the type of thing that I've seen a tiny spark 100 times and never thought a thing about it, but this is the first time it happened when I was working on a wall with newly concealed wiring - so I was paranoid

btw, last night I kept plugging things into different spots "just because I could" ha ha, did I mention I love having power out there? ha ha