A few weeks ago, an 800A breaker tripped and could not be reclosed. So, it was replaced. The new breaker tripped several times, and a recording DMM left on it showed a maximum load of 620A. Each time, the investigating technician couldn't identify a fault before reclosing the breaker.
The plant manager had a tech place a bypass jumper around it. "We've got an instrument monitoring the current and if it gets too high someone can just pull the handle." He wants you to figure out why the breaker "doesn't hold." What should you do?
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