Infrared inspection for electrical problems

[John McKenna]

I think not.

[Michael Larson]

Originally Posted by jmckenna1

I think not.

Tricky John.

Did the control preform it's intended functions?

[John McKenna]

Originally Posted by mlarson

Tricky John.

Did the control preform it's intended functions?

I'm having too much fun remaining tricky...
"I think not".

[Michael Larson]

John, if you want to call the board out as needing repair or replacement, it's your call.

I wasn't there but I sure would not rely on the IR image alone to say there was a problem. But maybe that's just me.

[Richard L. Bennett]

Super tec here

Do not hand touch board with power on for a temp check

General rule if too hot to touch it is too hot --

If working ok I would go home

If not working ok you should have found the issue without the IR camera

Remember the board might be ok but the problem might be what the board is controling

This is fun but too far up stream for a home inspection

rlb

[Michael Larson]

Originally Posted by rbennett

If working ok I would go home

If not working ok you should have found the issue without the IR camera

Remember the board might be ok but the problem might be what the board is controling

This is fun but too far up stream for a home inspection

rlb

Well super tech I am in full agreement with you but wasn't if fun watching Mr. Lone Star squirm a bit?

[John McKenna]

Originally Posted by rbennett

Super tec here


General rule if too hot to touch it is too hot --




rlb

Exactly... simply a no brainer.

[bdoles2]

General rule if too hot to touch it is too hot

Hell that's common sense!

I don't think you need an engineering degree to figure that out!

[Michael Larson]

Originally Posted by bdoles2

Hell that's common sense!

I don't think you need an engineering degree to figure that out!

You need something more than you two are working with.

Sorry guys, I respect you but your out of your field of expertise on this one.

[John McKenna]

Teach us.

[Michael Larson]

Originally Posted by jmckenna1

Teach us.

I've been trying but you wanted to play games instead.

Richard had it right except maybe if too hot to touch part. There are many things to hot to touch that are working as intended.

In this case, without knowing the component involved I have no opinion on whether it's too hot or not.

[John McKenna]

Originally Posted by mlarson

I've been trying ...
I have no opinion on whether it's too hot or not.

OK.. that's what I thought you said before.
Thanks. My only game is to let you talk.

[bdoles2]

I'm not so sure John was really calling it out, but maybe he was. I only remember him saying it was "a tad bit hot". With IR a lot of stuff might be a tad bit hot, but aren't called out. But it may be more of an awareness as to "watch this component, it's in the first stages of failure". What you might call "predictive maintenance".

So can't you teach us on what might make that board so hot, regardless of what it's connected too, or what brand. Just teach us on simple circuit board theory. Throw some scenarios out there for us. I'm all for learning, if you can teach us.

[Michael Larson]

Brian,

I would be glad too but as I said earlier, I don't know what component is showing as "hot".

The visible light pic and the IR pic don't seem to line up very well so I can't tell what part of the board is "hot".

Since this board is not a readily accessible part, the requirement for maximum temps are only limited by the maximum operating temperature of the device in question.

Excess heat may indicate a problem but in this case there just is not enough information available.

A couple of examples:

Some resistors are constructed of materials that can withstand very high operating temperatures without breaking down.

Triacs, Scrs's and high power transitors are switching or devices that can pass a lot of current and may run very warm(or hot) depending on the load they control.

Many are provided with heat sinks(finned cooling with or without fans or thermal masses) to dissipate the heat.
But if a device is of the type than can operate at higher temps without a heat sink, a smaller less bulky and less expensive control can be designed.

In the days before switching type power supplies, large, heavy transformers were used to provide power to lower voltage circuits. They were not very flexible as to input voltage and frequency in world market and were now where close to the efficiency of power conversion as today's power supplies.

As my friend with the Orange shirt says "Hope this helps"

[Richard L. Bennett]

Printed Ckt boards can not be generalized in a short posting.

They can be found in a watch - bomb - stove - TV - human body - HVAC -

They can be many layers thick like plywood

Hot spots are caused when current and resistance are high. High current conditions are to be found in power supply areas. With nothing hooked up to a ckt board but power everything should run cool. One area that might show a little heat would be components related to power supply filtering.

The too hot to touch is a very general rule and it is not true in all cases. Some devices have to be very hot to work

Another rule is if it is smoking it is too hot.

Nothing can beat the working knowledge of the equipment that is in question.

rlb