Originally Posted By: jtedesco
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Mark’s Service Call, at a “Flea Bag Hotel” in California!
Arriving at this Service Call, at a "Flea Bag Hotel", the Manager tells me that after changing some breakers last night to 30 A , because the lights were flickering, one of the boxes here was glowing red. This was in a "Trash Room" that gets bug bombed daily; all of the surfaces in this room are sticky with pesticides!
And, although not visible in the pictures, the bottom of the Electrical Panel was filled with Dead Roaches. I had to scrape them out to be able to continue. The white stuff is rat poison to keep this roach graveyard safe from those pesky rats!
Anyway, the electrical problem ......! The large black box to the left, is an older style telephone distribution panel, the discoloration of the hinges is from when it was "glowing red" the night before.
First, I shut everything in the panel off, yank out the 30 A breakers, and throw them in the trash. The Manager says, "But those are the new ones?!"
Those are ones missing here in the picture. The flexible metal conduit (Greenfield or Flex) on the left has arced through, with the phase conductor surrounded by the metal of the phone panel cover that had melted back.
So why didn't the breaker trip? I had a hunch, so I broke open the case of the breaker to find out. Yep, just as I thought, it was filled with roach bodies! It mechanically could not open!
I didn't get a picture of this because I was too disgusted!
But there is another reason here too. Why did the flex arc out first, allowing access to the phase conductor later? Grounding problem right?
Before we go there, notice that the neutral bar in this "Sub Panel" is attached to the box with self tapping screws. Effectively bonding the neutral and ground here, a Code violation that kept the power going much longer than it should have been on.
So, the flex arced to the grounded phone panel.
There must have been a short maybe? And the Phone panel had the better ground, but the electrical panel has that neutral bonded to ground there. There's no neutral either? I check voltage to some places...... 119V O.K., but I know it's not carrying a load.
So what about that conduit ground........? It's blown open!
So what about that ground from the phone panel, not that it matters, its blown open too!
This is the result of the FIRE in the phone room one floor below. Note the melted mass in the lower right of the phone panel, that's the phone riser as to goes through a sheet metal covered wall. This is where it blew open.
The sheet metal actually had a saving grace, in that it greatly improved the fire rating of the plaster and wood lathe wall behind it. The unsupported conduit to the right is the riser for the electrical panel above.
One more floor down is another part of the problem. In the unsupported 4 inch square is the bad neutral splice.
I cut it out and measure 105 ohms! Did, I mention this subpanel is on a 70 A breaker, using #10's as the feeds from the basement to the fifth floor?
Yes, that is a needle disposal container to the left! And, after I shut the power off, all the junkies are following me around complaining that they can't watch TV!
All of these rooms are coated in DDT, and it's now my job to fix this mess on a sunny Friday afternoon! (So my Boss "can sleep at night", knowing that there wont be a residential hotel fire with his name on it.) I have early dinner plans with my Fianc?, Best Man, and out of town family right after work.
And, the jobs I was pulled away from are complaining that I'm not there.
All I want to do is go home and take a shower, and contemplate another line of work!
Mark A. Heller, Master Electrician, California
Joe Tedesco, NEC Consultant