Hot Electrical Service

[William J. Decker]

1) The subject "hot spot" was not energized.
2) Safe to do. to exposed breaker areas (just not the lug or contact screw).

Hope this helps;

[Michael Larson]

Originally Posted by wdecker

1) The subject "hot spot" was not energized.
2) Safe to do. to exposed breaker areas (just not the lug or contact screw).

Hope this helps;

Unless I have totally misunderstood, the hot spot in the photo is a conductive and energized part, not the breaker.

[William J. Decker]

Originally Posted by mlarson

Unless I have totally misunderstood, the hot spot in the photo is a conductive and energized part, not the breaker.

No. The hot spot was the screw that held down the breaker. Not energized.

Make sure you buy a good quality contact. Isolated.

Or, you could just use a good, non-electric (non-thermocouple) contact thermometer. That also works.

[John McKenna]

Originally Posted by wdecker

No. The hot spot was the screw that held down the breaker. Not energized.

Make sure you buy a good quality contact. Isolated.

Or, you could just use a good, non-electric (non-thermocouple) contact thermometer. That also works.

You make it too easy. Is that allowed?

[Chuck Evans]

Actually the hot spot was the screw that secured the buss to the backplane.

It is energized.

[Michael Larson]

Originally Posted by cevans

Actually the hot spot was the screw that secured the buss to the backplane.

It is energized.

Thank you.

[Kevin A. Richardson]

Originally Posted by wdecker

See here:
http://us.fluke.com/usen/products/Fluke+561.htm?catalog_name=FlukeUnitedStates&categ ory=INFTHE(FlukeProducts)

A Pyrometer (type K thermocouple) is a nice tool to have in your tool bag. It can come in handy, especially if you venture out and do any commercial infrared work. It is particularly helpful when evaluating motors.

However, it's not really needed for the thermal anomaly we are talking about in this thread. I'm certainly NOT going to put a thermocouple inside an "Energized" electrical panel.

You can get most if not all the data you need just by using your Imager and applying the principles of the Delta-T method.

A Qualitative analysis, in most cases, will suffice for what we do as residential home inspectors. However, taking the time to learn the proper method of taking an "Absolute" or accurate temperature measurement will enhance your abilities and make you a better Thermographer.

Kevin

[Jason Kaylor]

Originally Posted by krichardson

A Pyrometer (type K thermocouple) is a nice tool to have in your tool bag. It can come in handy, especially if you venture out and do any commercial infrared work. It is particularly helpful when evaluating motors.

Kevin

I have a lot of guys that use this in conjunction with an IR camera for electrical/mechanical/industrial/motor/etc applications. http://www.aikencolon.com/Fluke-54-2...er_p_1598.html IR thermometers have the same downside flaws that the IR camera does, so most guys prefer contact.

For you guys that might have a Testo 435 you can simply add on a probe to it for about $100 and accomplish the same thing.

Jason Kaylor – JJ
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[David A. Andersen]

You can also add a head to determine load (amperage) on the hot circuit.

Which to some is important to know so you can determine the potential of the problem.

[David A. Andersen]

I see that some readings are well below the 247 degree screw. Is the screw going to fail at a 172 degree delta? We can all agree that it should be tightened if it is loose. It may also be enlightening to know what the temperature will be under a full load (without possibly burning the house down from loading the panel to see).

The 103 degree delta on the breaker is substantially lower than the 172 delta reported at the screw. Is the direct temperature inside the breaker 247F degrees?
So which one do we elect to use?

Does the indirect 103 F delta still require "IMMEDIATE ACTION" IAW the standards we are using here?

The issues that I find in the real world is that electricians inherently do not accept your inspection report. They do not use thermal imaging. So how are they supposed to repair and further evaluate at the same standards of which you are reporting?

They may turn off the main and put a thermometer on it. Are they going to get the same result? Unlikely.

It's a contact thermometer subject to error? Yes, for many reasons. Will their diagnosis conflict with yours? I think so.

Is a home inspector required to evaluate? No.
Is a home inspector with a thermal camera evaluating? Yes.
When you pull out your evaluation tool, should you be falling back on "a home inspector is just a generalist" and does not need to properly evaluate the situation?

The capability is there to provide a substantially greater amount of information about the situation. It just requires learning the process and collecting the data which is already available when you pull out the camera.

Reminder: I am not discussing if this panel should have been called out in the first place. We are attempting a discussion to broaden our perspective of how we conduct our evaluations.

Chuck, I am not trying to downplay your find. I'm an advocate of gathering more information because I feel that all too many issues are ignored when they are in fact significant. Hot is hot and you found hot. My questions to you was requesting additional information on how you conducted your scan so I wouldn't be demeaning to you by reiterating the obvious procedures which you already know. Whether I'm using a thermal scan as a qualitative or quantitative evaluation, I always double check by taking just a little more time to determine if what I am seeing is actually factual. This is a thought process of "what if ?". I'm sorry if I offended you by apparently critiquing your process. If you want a suggestion on electrical evaluation, I would recommend always acquiring the load on the circuit and obtain the reflected apparent temperature. These are things that you cannot gather at a later time after you leave the inspection site or re-create the exact conditions at the time of your scan.

[Kevin A. Richardson]

I see that some readings are well below the 247 degree screw. Is the screw going to fail at a 172 degree delta? We can all agree that it should be tightened if it is loose. It may also be enlightening to know what the temperature will be under a full load (without possibly burning the house down from loading the panel to see).

If you measure a main breaker to be around 250 deg F, and make the assumption that the panel is not under full load, are you suggesting that you want to load the panel more - just to see if you can make it fail or just get a higher temperature reading? That's crazy!!

The 103 degree delta on the breaker is substantially lower than the 172 delta reported at the screw. Is the direct temperature inside the breaker 247F degrees? So which one do we elect to use?

Not following the logic behind picking cooler spots inside the area box (min/max). It's simple math. Take the max temp from ar1 and subtract sp1, which is ambient. The result is the rise over ambient.

Does the indirect 103 F delta still require "IMMEDIATE ACTION" IAW the standards we are using here?

The term "IMMEDIATE ACTION" is something I use in my inspection reports, but I clearly define it's meaning to my clients:

"IMMEDIATE ACTION: This designates Adverse Conditions for which evaluation by a Qualified individual is recommended as soon as possible for any necessary modifications or corrective measures. If, in the process of evaluating and addressing such conditions, it is determined that there are other Adverse Conditions present for which modifications or corrective measures are also deemed necessary, it is recommended that they be addressed at that time. It is further recommended that a copy of the appropriate portion or portions of the inspection report be provided to all Qualified individuals retained to evaluate and/or perform modifications or corrective measures to address Adverse Conditions documented in the Inspection Report."

If we are going by the NETA standards, then this would be a "priority 1 - Major Discrepancy, Repair Immediately"

Repair Priority 1 would be a Delta-T over ambient air temperature of >40 Deg C (104 Deg F).

The issues that I find in the real world is that electricians inherently do not accept your inspection report. They do not use thermal imaging. So how are they supposed to repair and further evaluate at the same standards of which you are reporting?

Many Qualified Electricians do use Thermography. If I get a call from an Electrician that questions my report and who is not familiar or trained in the use of Thermography, I try and educate them.

Here is another excerpt from my inspection reports that helps with this issue:

"It is recommended that a copy of the appropriate portion or portions of the inspection report be provided to all Qualified individuals retained to further evaluate and/or perform modifications or corrective measures to address Adverse Conditions documented in the Inspection Report.When work requiring a permit is performed without obtaining the proper permit and inspections, that work may be considered nonconforming and illegal by governmental building code, ordinance, and regulation agencies that are charged with the promulgation and enforcement of such codes, ordinances, and regulations. Nonconforming work may jeopardize the safety of persons occupying or entering the property. It may also adversely affect specific insurance coverage and the saleability of the property and may result in added costs in the form of additional fees and/or property taxes or other penalties.

The written observations and recommendations contained in this Inspection Report are based on the knowledge and experience of the inspector. You may receive different information from other inspectors, tradespersons, insurance adjusters, private or public personnel, contractors, building and System warranty services personnel, or other parties whose interests are different from the Company's interests. If you receive information which differs from that expressed in this written Inspection Report, it is recommended that such information also be obtained in writing on the appropriate company or agency letterhead, bearing all applicable licensing numbers, and signed by the individual providing the information.

When other parties state that a Component or an Adverse Condition designated Repair or Replace is safe and/or adequate at the present time, without the need for any modifications or corrective measures, it is recommended that those parties be asked to put such statements in writing accompanied by a signed letter stating that no action is necessary and that the Component or Adverse Condition identified in the Inspection Report is safe and adequate according to all industry standards and governmental regulations."

Is a home inspector required to evaluate? No.
Is a home inspector with a thermal camera evaluating? Yes.
When you pull out your evaluation tool, should you be falling back on "a home inspector is just a generalist" and does not need to properly evaluate the situation?

I agree with you!!

Kevin

[David A. Andersen]

If you measure a main breaker to be around 250 deg F, and make the assumption that the panel is not under full load, are you suggesting that you want to load the panel more - just to see if you can make it fail or just get a higher temperature reading? That's crazy!!

No! I was alluding to mathematically calculating what the temperature would be based on the load at the time of the scan versus maximum circuit load. This is only considering a 100 Amp load on this 200 Amp Panel.


That is why I am an advocate of taking a load reading to determine "potential temperature rise". Even if you are unable to make the calculations, finding a 95° breaker with a 2% load can be considered a significant issue.

Yes it is crazy! No one should consider maxing out the load on the circuit just to see what happens!?

Not following the logic behind picking cooler spots inside the area box (min/max). It's simple math. Take the max temp from ar1 and subtract sp1, which is ambient. The result is the rise over ambient.

I have asked for a digital picture, and no one has explained why that one screw is so much hotter than anything else in the panel.

My reasoning for mentioning this lower temperature breaker is because this is the component likely to fail at these temperatures, not the screw.

I'm not saying that this screw cannot be a problem or add to a problem by adding heat to the more vulnerable components in the panel through conduction, radiation and even convection.

By all means, tightening of the screw should be addressed.

I do not personally agree with taking the max temp from ar1 and subtract sp1, which is ambient. The area box ambient reading is being effected by reflected energy from the hotspot. Convection will also increase a low temperature area in the immediate area. I also do not like to assume that the high temperature indicated by the camera is the true high temperature. In this case, that high emissivity black screw may have a tool mark from installation that changes the emissivity from what the camera is set at. I prefer to pick my spot. We cannot assume all parts of the circuit breaker panel to be .95. If this were the case, you could not differentiate the components within the panel in the thermal scan. The area measurement tool does not differentiate between emissivity differences.

This scan shows a crack in the circuit breaker case. The camera will pick up on the higher temperature in the area measurement tool. The difference in this case will be between a direct and indirect measurement. So in fact it is inaccurate to assume that the high temperature pixels detected is the same as the indirect breaker temperature.

[Kevin A. Richardson]

David,

Think what you want. I believe you are making this WAY too complicated!!

I do not personally agree with taking the max temp from ar1 and subtract sp1, which is ambient.

Then you don't agree in following basic principles and standards that were developed from years of experience far greater than you or I.

It's not necessary to "Qualitatively" analyze every defect. However, that appears to be in your nature. Nothing wrong with that, I guess

Take care,

Kevin

[David A. Andersen]

These are just things to consider.

This thread is about expanding the thought process, not making fun out of any one or saying what is right or wrong.
Thinking outside the box gives a perspective on what is going on.
That's all...

Not trying to make thing a big deal as so many here think.
Just trying to make everyone think.

One other question I forgot to mention; Repair Priority 1 would be a Delta-T over ambient air temperature of >40 Deg C (104 Deg F).

Does this standard not require a minimum load to be applied on the circuit to make it relevant/applicable?

If the answer is yes, then the very first question I asked on this thread " what was the load", was a relative question and still has not been addressed.

I understand that with a temperature split this great it may be unnecessary to determine the load, however I am advocating this thought process for conditions that are not quite so obvious and are frequently overlooked in the process. The concern is more about things that are not reported that are relevant rather than the obvious that may not be.

I like the added verbiage that you put in your reports. Are they available for plagiarism?

[Jason Kaylor]

Personally, I would probably keep things simple and just call an electrician out.

What is amazing here is how much information is available from different minds. I frequent many IR resources on the web, and these boards is one of the very best.

Jason Kaylor – JJ
VP of Sales
877/207-1244
AC Tool Supply
Fluke Thermal Imagers
FLIR Thermal Imagers
HotShot Hi-Rez Infrared Cameras
Fluke TiR1 Resources
FLIR B60 Resources
Retrotec Duct & Blower Door