Now the OT is really over. Really. It is. I think.

I love "The Mill". Just when we're packing up gang-boxes from the furnace job, putting our tools in our cars, and wondering where we'll be working next week (or, in my case, already on another job)....BANG! A cable blows up somewhere. The last two weeks we've been working on a set of 250v DC crane feeders. This is not an ordinary crane. It's rated for 400 tons and is used to move the ladles from the LMF (Ladle Metalurgical Facility) to the top of the continuous caster. This is a picture of the same type of crane tilting a ladle to pour out the molten steel. There are 16 cables (8 positive, 8 negative) size 500 kcmil, providing 3200 amps of current to this crane. Some of the feeders themselves melted. The problem was first noticed when a steelworker walked past a manhole cover and noticed steam coming out of it. Upon further investigation, 5 of the 16 cables were found to be open. The steam was caused by the current flowing between cables, which heated up the water in the manhole.
For each of the 5 cables, we found several feet of missing conductor. That's right, several pounds of copper were simply boiled away. The cause was traced to improper splicing. The splice connectors weren't properly insulated, allowing water intrusion (the cables were submerged), which caused a short between DC positive and DC negative cables and ground, which caused the cables to heat up. A lot.
So I went from working in a manhole, 20 ft. underground, next to 15kV, 5kV, and 250vDC cables to a remodel job in a church, installing 2'x4' light fixtures. Soon, I'll be going back to Cleveland Metroparks Zoo to continue the HV cable job I began last summer. What diversification in our line of work!