×
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

variable speed primary chilled water system

variable speed primary chilled water system

variable speed primary chilled water system

(OP)
What is the best control strategy for not going beyond a chillers maximum rate of flow change, while still controlling the VFD's based off of zone differential pressure.  IE if the controller sees a sudden drop in zone dp, it will increase the drive speed to compensate. In doing so, you could exceed the recommended 10% per minute change in flow rate.

RE: variable speed primary chilled water system

The recommended maximum % change in flowrate generally corresponds to a temperature control with a precision of +/-0.50C and it depends upon how tight a control you require. However, you can have your VSD run with a set ramp up rate to match the recommended maximum change.

This is for a variable primary flow application. If you have only secondary variable flows, this doesn't matter at all.

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