General Electric SEDA24AT0100, 2 Pole, 100 Amps
Sometimes we get calls from a customer that is in a real jam and has limited resources or time to get out of it. And sometimes these problems are over small pieces of electrical equipment, such as a replacement General Electric circuit breaker, two pole 100 amps. We got such a call just before Christmas. A home owner’s electrician needed a replacement circuit breaker, 2 pole 100 amps, for an old home. The existing circuit breaker would not latch closed. They had limited information on the old circuit breaker. They would have changed the whole panel but they couldn’t get it done before Christmas.
First we explained they had to contact the electric utility because they were changing the main breaker for a house. We sent them two styles of recondition circuit breakers because their information was not specific enough. We told them to use the replacement circuit breaker that was correct and to return the other breaker to us. Their ‘replace circuit breaker’ problem, as they called it, was solved and they had lights for Christmas. They returned the other breaker to MIDWEST. Their problem wasn’t because they needed an unusual replacement Square D circuit breaker or replacement Cutler Hammer circuit breaker. Their problem was because the location was Hawaii. It was a big problem for a small customer, but it made everyone feel great that we took care of them for Christmas.
MIDWEST had a customer that seemed to call us about every 5 to 6 months for a replacement circuit breaker. This went on for about three years, before we noticed the pattern. We recognized it because he started calling the same Engineer. We asked why he needed so many reconditioned replacement circuit breakers over the past two or three years. It seems their facility was built in the 1970s when copper was so scarce and expensive that many projects were built using aluminum cables. Unfortunately some installations did not use the correct lugs or failed to install the lugs properly. We were very surprised they didn’t have these problems, or worse, decades ago. We asked them if they still had a couple of the old damaged circuit breakers laying around. Could they send us one or more of the old circuit breakers that had been damaged, so we could inspect them and give some recommendations on how to prevent future problems. Inspection of two of their used circuit breakers that had failed, showed extensive heat and arcing damage at one or more of the load side lugs. We have seen this type damage many times and it invariably was caused by cables that had become loose inside the lug or lugs that had become loose at the breaker connection. One of our senior engineers worked in electrical construction during the years aluminum cables were used. He explained how this could be dangerous and he also was very surprised they didn’t have problems many years ago. He said a lot of new circuit breakers and MLO, ie main lugs only, panel boards were damaged when the aluminum cable terminations failed in the years after installation. He had one strong recommendation. Hire an old time electrician who remembers those days and knows from experience what has to be done to correct things. He said this can be a challenge. But, if they don’t do something, they may lose more than an occasional old circuit breaker. He also said to be extremely careful when installing a replacement circuit breaker. Always turn all the power off, including the feeder into the old power panel or panelboard. Safety first.
By Jason Honick
The question often comes up. The answer: to a limited extent yes. Since molded case circuit breakers typically cost less than other types of breakers, cost effectiveness of rebuilding molded case breakers is a top concern. On one side of the spectrum older smaller molded case breakers would not be good candidates for a rebuilding procedure. However rebuilding procedures vary with the device at hand. For example, cleaning or replacing breaker current carrying contacts is a relatively cost effective procedure rendering it highly applicable to even some low cost breakers. Before going out the door our used breakers go through a series of checks per our Quality Control Program. As part of that program, breaker contacts would be tested for contact resistance. Based on those test results, the contacts would be cleaned or replaced if necessary. So in the overall view of things, the extent of molded case breaker reconditioning depends on the specific item at hand.