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backup relay

noun
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Definition of backup relay

: a secondary relay to protect a power system against faults in the event of failure of the primary relay to function as desired

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First Known Use of backup relay

1950, in the meaning defined above

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The first known use of backup relay was in 1950

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Cite this Entry

“Backup relay.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/backup%20relay. Accessed 10 December 2019.

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