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Old 12-03-2014, 10:35 AM   #25
greysailor
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City: Matagorda Bay
Vessel Name: Salty
Vessel Model: 2005 Defever 44
Join Date: May 2013
Posts: 227
Quote:
Originally Posted by High Wire View Post
We use series breakers in a nuclear power plant for motor loads that penetrate primary containment. One breaker is setup specifically to protect the motor. Because its a motor, there are design conditions that must be met and verified through periodic testing. The other breaker is sized specifically to prevent damage to the primary containment penetration and has completely different design and testing requirements. Neither breaker alone can meet both sets of requirements and both must operate independantly. Other than that, I can honestly say that in 40+ years in the electrical field, I've never seen 2 breakers used for one load that werent mechanically ganged together to trip at the same time until this post. Me thinks the installer was more of a mechanical guy.
Wow! Archie you sure brought back memories of an earlier life for me....countless hours sitting in front of an old SR76 or EPOCH test set shooting penetration breakers during refueling outages! Nice to know there are a few old power nukes still afloat.
Back OP's subject...I agree this was probably something configured by a "boatyard electrical expert", and lacks basis in both theory and application....Replace the two breakers with one that is properly sized for the load.
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