×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

reverse power relay (32)

reverse power relay (32)

reverse power relay (32)

(OP)
Can anyone explain simply how a reverse power relay senses that the power is indeed reversed? thanks Dortheo.

RE: reverse power relay (32)

The relay measures the circuit voltage and current, as well as the angle between them.  When the current lags the voltage by more than +/- 90 degrees, the real power flow is in the reverse direction - the reverse power relay is sensitive to the real component of the current (kW).

RE: reverse power relay (32)


An early term for induction-disk relay operation was the “wattmetric” principle.   A reverse-power relay develops torque in its disk, exactly like a watthour meter does from voltage, current and phase-angle quantities.  In the relay, a set of contacts are linked to the disk instead of a counting mechanism.  Applications for reverse power protection may be single or three phase—often used to protect the prime mover of a three-phase synchronous generator.
  

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources