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Archive for May, 2011

400 Amp Bus Plug Blocked by 2″ Pipe

May 23rd, 2011 Comments off

During an Infrared Scan, or Thermographic Scan, of the electrical distribution system of a new account, MIDWEST’s Thermographer noted in his report a strange bus plug set up. A 200 amp Cutler Hammer bus plug had a 2 inch pipe installed right in front of the cover. The pipe was 3 inches from the bus plug cover and right near the operating mechanism. The pipe was just kind of hanging there. It didn’t have much support. It went to a huge molding machine near the Square D bus duct. So you couldn’t switch this 200 amp Square D bus plug from the floor and you couldn’t open the cover of the bus plug, if you had to, because of the pipe.  Who in their right mind would do this?  As it turns out, they had an emergency and had to get a temporary line to the molding machine as fast as possible. Apparently the line carried plastic used in the molding machine and this machine was their main money maker. So they just installed pipe temporarily as quickly as possible. And six years later, the temporary pipe was still there. It more or less had become permanent.  Temporary installations evolving into permanent, is not an unusual occurrence. In the real world, production rules.  And like it or not, the same rules that caused a temporary pipe installation, also prevent the permanent installation. In the electrical equipment world, this is somewhat self correcting when the equipment gets unhappy with a bang.  Bus plugs do fail if they are ignored too long.  Whether a GE General Electric, Square D or Cutler Hammer bus plug, it will eventually fail if ignored long enough. When these things happen, those temporary fixes come back to bite you.  

Rust, Old Bus Plugs Biggest Challenge

May 5th, 2011 Comments off

 

Cutler Hammer Bus Plugs For Sale - Cat. #CP2HD465

Cutler Hammer Bus Plugs For Sale – Cat. #CP2HD465

Sometimes the biggest challenge MIDWEST runs into, when reconditioning old bus plugs and obsolete bus plugs, is rust. Ironically this biggest challenge usually has the easiest solution, scrap out the bus plug. Sometimes healthy parts can be harvested from the rusted bus plugs, but care has to be taken to assure the recovered parts have not also been damaged by rust. The problem with rust is that it can be very insidious. Let’s say we want to recondition a Square D bus plug, Siemens Bus Plug or Cutler Hammer bus plug. It doesn’t make any difference. The rust doesn’t care. The problem is, we frequently don’t know the extent of the rusting until we have disassembled the bus plug and started the metal refinishing. The surface preparation may reveal severe structural rusting that was not fully apparent cosmetically. Now we’re not talking about full blown metal failure where you could push your finger through the metal. That’s obvious. We are referring to non cosmetic deterioration that prevents professional surface reconditioning. And this is not always visually apparent. It might not even be discovered if a company just repaints on old ITE or Westinghouse bus plug, for example. MIDWEST is very carful of equipment from facilities that have been out of service and unheated for any period of time. Extensive moisture damage can occur and not be visible until MIDWEST begins the full reconditioning process. This is another reason we recondition and test our equipment. There can be hidden defects. Some structural, some functional, some electrical, and any of them could turn a bus plug into a piece of scrap metal.