Time and inverse time relay

[Hameedulla-Ekhlas]

Greeting all,
Please advise me for the following

independent or definite time relay: whose operating time is independent of current

Dependent or inverse time relay: Whose operating time depends on the current level


Am I write for the above information please advise me and if you have farther information please explain it.

 

[Hameedulla-Ekhlas]

Greeting all,
Please advise me for the following

independent or definite time relay: whose operating time is independent of current

Dependent or inverse time relay: Whose operating time depends on the current level


Am I right for the above information please advise me and if you have farther information please explain it.

 

[jim dungar]

These are terms usually associated with protection relays like ANSI overcurrent numbers 50 and 51.

A definite time relay operates without any intentional delay once its pickup point has been reached. For typical circuit breakers this corresponds to the Instantaneous (or magnetic) part of their curve.

Inverse time relays depend on a certain amount of current existing for a certain amount of time (more current = less time). There are many different curve shapes and slopes, IEEE, IAC, and IEC among others, that can be followed.

 

[jghrist]

Greeting all,
Please advise me for the following

independent or definite time relay: whose operating time is independent of current

Dependent or inverse time relay: Whose operating time depends on the current level


Am I right for the above information please advise me and if you have farther information please explain it.

You're right on the definite time and inverse time overcurrent relays. I am unfamiliar with terms independent and dependent in relation to relays.