Infrared inspection for electrical problems

[Kevin A. Richardson]

This one was from yesterday's inspection.

Kevin

[David A. Andersen]

Yup!

I call that an issue!

Enough said!

[John McKenna]

HVAC electrical circuit board a tad hot.

[Mario A. Kyriacou, CHI]

Where did Mr. MacNeish go? </IMG>

[Larry D. Kage]

Originally Posted by dandersen

Yup!

I call that an issue!

Enough said!

Agreed,...but relative to the center of the sun, it is cold.

[Michael Larson]

I can't correlate the two photos as they seem to be taken from a different angle so I can't tell what area of the control board is hot.

I would point out that some heat sinks mounted on components run very warm and even hot to the touch, especially motor control SCRs and TRIACs

Without knowing if the emissivity setting is correct for the "hot part" I'm not sure how useful the 234 deg. indication is.

If this board was working normally, there may not be a problem.
IMHO guys based on over 30 years as an electronics tech and engineer.

[John McKenna]

Originally Posted by mlarson

I can't correlate the two photos as they seem to be taken from a different angle so I can't tell what area of the control board is hot.

I would point out that some heat sinks mounted on components run very warm and even hot to the touch, especially motor control SCRs and TRIACs

Without knowing if the emissivity setting is correct for the "hot part" I'm not sure how useful the 234 deg. indication is.

If this board was working normally, there may not be a problem.
IMHO guys based on over 30 years as an electronics tech and engineer.

How hot would you consider to be normal, based on your experience.?

[Michael Larson]

Originally Posted by jmckenna1

How hot would you consider to be normal, based on your experience.?

Warmer than you can hold your fingers on.

What part is shown to be hot?

Was the control operating normally?

What is the material and emissivity of the "hot" part?

Is this one "normal"? I have now idea.

Junction temps of Triacs can be as high as 150 Deg. C (not F) > 300 deg.
Note: This is an internal semiconductor rating.


http://www.eetasia.com/ART_880050686...P_7d0a2fdd.HTM

[John McKenna]

Originally Posted by mlarson

Warmer than you can hold your fingers on.

What part is shown to be hot?

Was the control operating normally?

What is the material and emissivity of the "hot" part?

Is this one "normal"? I have now idea.

Junction temps of Triacs can be as high as 150 Deg. C (not F) > 300 deg.
Note: This is an internal semiconductor rating.


http://www.eetasia.com/ART_880050686...P_7d0a2fdd.HTM

Just answer the question with a general high and low (ie... 120F to 175F)...
Can you answer please?

BTW... all my IR photos are apparent temps only... within a percentage of true....
Close enough to see a red flag.

I see the IR image as an issue and as you said...

Is this one "normal"? I have now idea.

[Michael Larson]

Originally Posted by jmckenna1

Just answer the question with a general high and low (ie... 120F to 175F)...
Can you answer please?

BTW... all my IR photos are apparent temps only... within a percentage of true....
Close enough to see a red flag.

Nope.

That's about the same as asking what the normal temp of a circuit breaker is.

Sorry John. Not being evasive but there are too many variables.

If I had experience with that control board and it's typical observed operating temp them we would both know what to expect and how to report it.

Maybe Charile B. w ill be along and have a better idea for this type of control board.

I honestly can't say either way.

Added:
When I was a tech I could usually grab another device of the same type for comparisons.
I would also note any evidence of burnt or discolored from heat components for clues.

[John McKenna]

Michael,

You first said

If this board was working normally, there may not be a problem.
IMHO guys based on over 30 years as an electronics tech and engineer.

Now you say

I honestly can't say either way.

OK... thanks.

[Michael Larson]

Originally Posted by jmckenna1

Michael,

You first said



Now you say



OK... thanks.

John, please pay attention.

Did you ever say if the board was working normally?

[Michael Larson]

John???

[John McKenna]

You had so many answers, I'm not sure...

[Michael Larson]

Originally Posted by jmckenna1

You had so many answers, I'm not sure...

Was the control working normally?