×
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

Thermographic scan

Thermographic scan

Thermographic scan

(OP)
Is there any prescription that say from what voltage or current thermographic scan is relevant? If not, from yours experience can you give some values?
Thank you!

RE: Thermographic scan

A thermographic scan is probably more suitable for current carrying components and connections since the I-squared R effect will readily show up with infrared.  Keep in mind that the current probably should be at least 50 % of rated current or greater to have maximum benefit of detecting potential problems.  At a light load condition, the temperature rise won't be great enough to provide a reliable indicator.

While I lean more to using it for current carrying components, it will also provide effective results for early warnings with faulty arresters where moisture ingress leads to thermal runaway.  We've also had good results in checking some of the newer solid dielectric potential transformers.

I don't think there is a limited voltage range for IR.  We employ it with transmission voltages of 115, 230 and 500 kV and distribution voltages of 4, 12.5, 13.2 and 34.5 kV.

In a three-phase installation, I think using the maximum temperature is not as important as relying on the comparative temperature on like components on adjacent phases.

RE: Thermographic scan

magoo2 has given a good response.
just remember than an IR scan is a snapshot of the conditions at the time and load conditions when the scan is performed.
if you are going to use it as a predictive tool you need baseline scans for low, normal, and high load conditions in order to detect possible deteriorations of components and connections.

again magoo2 hits a homerun with his last statement on comparative readings.

Steven C
Senior Member
ThirdPartyInspections.com

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