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CL protective device cycles?

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    CL protective device cycles?

    A current limiting protective device will cut off the maximum peak fault current for currents within its current limiting range is less than which of the following?
    I was sure this was 3 cycles....
    This might be too high maybe 0.5?

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    Quote Originally Posted by Havik21 View Post
    A current limiting protective device will cut off the maximum peak fault current for currents within its current limiting range is less than which of the following?
    I was sure this was 3 cycles....
    This might be too high maybe 0.5?
    i always thought instantaneous was no intentional delay, i would choose lowest option.

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    Quote Originally Posted by Havik21 View Post
    A current limiting protective device will cut off the maximum peak fault current for currents within its current limiting range is less than which of the following?
    I was sure this was 3 cycles....
    This might be too high maybe 0.5?
    Per Chapter 1. page 3 of Protective Relaying Theory and Applications by Walter A Elmore:

    Applied to a relay, high speed indicates that the operating time usually does not exceed 50ms (Three cycles on 60-Hz base). The term instantaneous indicates that no delay is purposely introduced in the operation. In practice, high speed and instantaneous are frequently used interchangeably.
    Remembered this line and thought it may be applicable.

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