×
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

thermal time constant

thermal time constant

thermal time constant

(OP)
Hi!
Does anyone know where can I find the thermal time constant of electrical asynchronics motors?
thanks in advance.

Martin

RE: thermal time constant

Ask to the motor manufacturer.
 That constant will depend on the motor materials, current pattern and cooling system. Could be quite different for different brands.

RE: thermal time constant

(OP)
Thanks aolalde!
I know wath you say, but the manufacturer dont want to give that information because it's their "know how".
That's why I was looking for another way to find that information.
Thanks again
Martin

RE: thermal time constant

Ask the manufacturer for the TAU value, tell him its for protection relay setting. He should give it to you.
This value is different for every manufacturer and model.

regards,

Danny

RE: thermal time constant

If you want to do a test, you can do it, just measure temperature vs time after a motor shutdown.  Plot it on a log(Temp) vs linear (time) scale and the slope should be:
 -1/tau

I had posted some shutdown temperature patterns for motors at our plant a few years ago... might be of use as "typical" values.  Unfortunately the search feature at this site does not allow you to combine different criteria such as posts by a specific user containing a specific keyword (pick one or the other... keyword or user). I have too many posts to look through them all.  

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: thermal time constant

Try using google to search for it.  Put in the conditions, which google will let you do, and then add site:eng-tips.com at the end of the search string.  I don't know how use of the google button on the eng-tips pages would work compared to using google directly.

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