Time delay relay with low forward relay


Thread Starter

raj kishor

can anybody let me explain in details why a timer (time delay relay) is
provided in series with a low forward relay and a reverse power relay in
generation protection? is there be any problem if a timer won't provide
along with a low forward relay?

waiting for replies.

Raj... I have taken the liberty of interpreting your query to mean, "Is the 'time-delay' feature needed in addition to the 'reverse-power' feature?" My answer is Yes!

Some Protective System practitioners have been known to eliminate the 'time-delay' because the effects and consequences of "motoring" have been quantified. What is over looked is the fact that the 'time-delay' prevents unwarranted operation that could occur during power swings, or when the input-energy is "hung-up" for mechanical reasons!

Regards, Phil Corso