August 31st, 2017 Leave a comment Go to comments

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  1. Sandra
    April 4th, 2013 at 08:04 | #1

    If you have a spare circuit breaker in your electrical panel, it is not in use and is labeled “Spare”, what is the safest position for the spare breaker to be in – ON or OFF. And, is there any Code, regulatory or guidance document I could reference on the state of spare circuit breakers?

    April 10th, 2013 at 09:47 | #2

    MIDWEST recommends keeping spare breakers in the off position so the load side terminals are de-energized, reducing shock and fault hazard. We do not know of regulations governing spare breakers.

  3. December 13th, 2013 at 21:19 | #3

    Happened across your blog, it brings back memories of a previous career — in the 1980s I was an electrical engineer with Siemens designing switchgear before going off to get my doctorate in biology. One of my favorite dumb customer stories: somebody tried to use one of the auxiliary contact blocks on a three-phase contactor as an additional power circuit. The power poles on this thing were rated something like 600V, 100A while the auxiliary contact blocks were rated something like 220V, 2A. So of course the first time that little auxiliary contact block tried to interrupt three times its rated voltage and 10 times its rated current the poor thing vaporized. Never mind reading the specs, the difference in physical size between power poles and auxiliary contact blocks should have been obvious.

  4. Brian
    January 31st, 2017 at 08:47 | #4

    Does anyone maybe still have any manuals on a 1985 Merlin Gerin DA air circuit breaker?

    February 1st, 2017 at 10:43 | #5

    MIDWEST has checked it’s Archives and unfortunately does not have information on the Merlin Gerin 1985 generation DA circuit breaker.

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