Last week I changed a main panel in a nearby house. The existing panel was an old wooden box type with porcelain rewireable fuses, and a separate voltage ELCB. The whole lot came out to be replaced with a modern C/B panel and main GFCI. The chap was most happy that I could do the whole changeover live and avoid a call-out charge from the utility.
Talk about being careless though. A couple of days ago he called me back, as during his on-going renovation work he managed to put a plasterboard screw straight into the main service cable.
He couldn't have gotten it closer to dead center of the cable if he'd been aiming for it! Said there was "One h*** of a bang!" I told him I wasn't surprised and to be grateful that he's still around to pay the PoCo call-out charge PLUS their labor & material for a new feeder.
A student of mine was called to a house to perform some work. He was working near the meter, and being somewhat cautious, but not overly concerned, he noticed that the cable entered the wall at a 90 deg. angle below the meter, went into the basement, and noticed it exited at a 90 deg. angle from the wall, all normal. What he could not see was they had taken a turn once in the wall. The NEC says you must terminate SEC as soon a practical, but as everyone knows, does not give footage, most jurisdictions in VA establish their own. These guys were just trying to hide their routing. He begins drilling with a 1/2" drill and Ship Augur bit. There are a few sparks and the drill is hung tight. He notices the bit begin to turn cherry red, then move up to the drill. The only thing he could think to do is to cut the seal and pull the meter, good choice. Gives new meaning to the term "infinite buss". I did get to see the drill (fried) and the bit that night, the bit had "drooped" under the weight of the drill. The PoCo did not even get mad at him.
George, Pulling the meter in a case like that is very dangerous. The meter socket is not designed to be a load break device. I see few choices in this case, but I sure hope the guy pulling the meter had full PPE on. Fire resistant clothing, full electrical rated face shield and hood and heavy gloves would be required for this type of work. Don(resqcapt19)
While I understand the underlying message from you, and totally agree that removing a meter under load can be dangerous, you really expect a fairly young guy to run to the truck, pull on full PPE gear, (as the wall begins to smolder, the redness brightens in the augur bit as it moves closer to the drill motor), THEN cut the seal and pull the meter?
I'd be tickled if he was wearing the protective eyewear and standard leather gloves I constantly remind my guys to wear while using power tools.
There wouldn't have been any chance to pull the main service fuse here, as this was on the feeder ahead of the meter panel. (In this case, there was an unusually long length of service cable inside the house structure.)
He'd built a new roof by laying rafters over the old ceilings, then realized all the cables (including the service feeder) were now trapped underneath the new timber. So he just notched the lower edge of each one for the cables before fixing the plasterboard over them.
The cable was the concentric type with neutral on the wire armor, so at least the screw he was touching made secure contact with the neutral before the point hit the live center conductor. It didn't take out any distribution fuses on the network - The feed was still live. It just vaporized the finely tapered end of the plasterboard screw.
[This message has been edited by pauluk (edited 12-04-2001).]
Hi, Don. I have to second what you said about requiring protective equipment for doing this kind of work. A few years ago, we had a late night fire at a house where there was no outside service disconnect. It is not accepted procedure for our Fire Department to attempt to remove a meter (especially one such as this which was passing tremendous fault currents through it from the burned-out wiring inside the house) for the reasons you mentioned. Before anyone could stop him, A young firefighter decided to "free-lance it" and remove the meter, while wearing only normal firefighting gear (hardly suitable for electric work). At the moment the meter jaw contact was broken, there was a spectacular flash that scared &*&*$*$% out of other firefighters nearby. I still to this day don't know what saved the firefighter from quite literally having his face burned off. Our PoCo has extremely slow response times when called to emergency service disconnects such as this. But your priorities are absolutely correct; I'd much rather lose a house than to lose a brother firefighter.
A friend and Electrical Contractor who shall remain nameless was drilling through the top of a can to tie in a new genny transfer switch for a turkey barn. No power-off was allowed and Y2K was looming, so he chose to do the work hot. When the hole saw broke through, it went straight into a 120V leg of a 120/240V 400Amp service and burst into flaming arcs of molten saw teeth. He was miraculously uninjured, but was shaken up for days. He did the rest of the barns with the services open.
-Virgil Residential/Commercial Inspector 5 Star Inspections Member IAEI