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Vulture38
Lv 6
Vulture38 asked in Science & MathematicsEngineering · 9 years ago

I have an electrical circuit diagram of a DC breaker. On it are two relays, annotated as NOA and NCOA.?

Any ideas what they mean?

Update:

Thanks, we got the normaly open/ normally closed bits.

1st Answer will get the 10, as we've just found the glossary in a distant table in the book.

2 Answers

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  • Lesus
    Lv 7
    9 years ago
    Favorite Answer

    Could be normally open and normally closed.

  • Newton1Law
    Lv 6
    9 years ago

    I would need to see the relays or have additional information but these appear to be an older rating given to contact operation, NOA - Normal Open Air, NCOA - Normal Close Open Air.

    Do you have more details on these units??

    Newton1Law

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