Sorry Charlie no stove today

but I did find a heat pump breaker that was roughly 100 degrees past ambient where connected to the buss blade. :-k

The panel in the cold garage was 45 degrees. The breaker warmed up to 145 deg at its warmest point.
Ther was also a nice little buzzing sound coming from it as well. and no I didn’t check the amp draw. :smiley:

IR000906.jpg

A 75 degree C breaker at 63 degree C I just don’t see the problem

I agree that the temperature is less than the max allowable, but I think Sean is calling it out for the significant temperature imbalance between each pole.

It would have been good to know the current draw, but I think Sean is doing the right thing being cautious and advising for further evaluation.

Hats off to you Sean, good work. Better to be safe than sorry.

Not to be hyper critical, but: It would be better to see a full frame IR image and a separate visible light image so that we can see more of what is going on. The primary use of PIP fusion is to sell imagers. It doesn’t help with analysis of possible electrical exceptions. It would help to see more of the conductor in IR.

The image should have a temp scale showing span and a marker showing ambient temp inside the panel or a similar component under similar load (but of course we don’t know the load). Comparison to a similar component under similar load is preferable to comparison to ambient whenever it’s possible to obtain.

If the rise is 100F above ambient it would qualify as Priority 1 exception when evaluated against the NETA Maintenance Testing Standard. Of course, temperature rise increases almost exponentially relative to increases in current, so it would be really nice to know actual vs. rated load of the circuit.

Please share how you report this phenomenon.

You are correct Sean calling it out even with out the amp draw its obvious to me there is a un-balanced temp between the two legs and on a A/C unit there is no 120 volt circuit all 240 so both legs should indicated the same temp. Ya did good . I have been known to call out as little as a 4-5 degrees differential between the legs. I know most electricians struggle with this idea of differential temps all they want to see is the overall rating for the conductor

Chuck is correct PIP is not the desired choice for electrical and you should always use comparision temps between the legs.

PS I am glad to see your checking these double pole breakers with IR you will find a lot of loose connections

Does this help?
Sorry I just didnt feel the need to get critical with this one.

IR000906.jpg

Yes looks much better still don’t like pip for electrical had 2stoves today myself one was a mess and one was just perfect the panel was even loaded great nice even amps on both legs and even temps

The reason that I ask how you report it and mention the specifics of the image is because presentation of the issue is important in order to properly guide the electrician when you ask them to further analyze the exception. Too many get ignored and discounted because of substandard reporting. What good does it do your client if the electrician simply discounts your report.

This thread provides a great example. Joseph Witt is very knowledgeable on electrical topics and is very analytical to boot. He is far more knowledgeable than the typical electrician that will be called out to perform “further analysis” on the situation. However, he is not a thermographer and shouldn’t be expected to be. The information and the image provided were not adequate to convey to him how to approach assessment of what was likely a bona-fide exception.

Conscientious reporting will provide client and contractors the information that they need to properly act on your observations - we are in the communication business. It also increases your credibility.

Proper reporting of thermography observations is always important.

Ranges and dryers are multiwire circuits meaning that everything on ranges and dryers are not 240 volts.

Clocks, timers, lights, ect. operate at 120 volts. Dryers will sometimes have a motor that is 120 volts and some ranges will have small heating elements that operate at 120 volts. Ovens with fans will sometimes have the motor at 120 volts.

You are correct I do not do thermal picture taking just because of the hype involved although I have attended the class that the Snell Group offers. When I am called to evaluate an electrical system where there are thermal pictures I do three things.

[FONT=Calibri]1- [/FONT]I take an amperage reading of the breaker to see if it is within the rating of the breaker
[FONT=Calibri]2- [/FONT]I check the tightness of the screws on the breaker and how tight the breaker fits the bus. I do this to all breakers in the panel every evaluation regardless of thermal imaging
[FONT=Calibri]3- [/FONT]I look at the image to see if the temperature is within 75 degrees C or 167 degree F

Example- If I have a range with all four top elements as well as the oven turned to high that is protected by a 50 amp breaker and each leg is within this 50 amps weather balanced or not, all screws are tight and the breaker fits tightly on the bus bars I sign off and leave.

What I am not going to do is start analyzing the range to find where the imbalance is coming from. It is in the design of the range and the manufacturer of that range knew what they were doing when they designed the thing.

Thermal imaging is a good thing when done properly and not used as a theatrical tool.
I can’t help but wonder how many does a pic of the range receptacle. I have found countless defects at the receptacle that was overlooked by the inspection process. When doing an evaluation I don’t stop at the panel. If the range or dryer is wired at the panel with four conductor cable I want to see the receptacle to be sure that a four wire receptacle is being used and the bonding jumper has been removed at the appliance.

Quick Tip While checking the amp draw at the breaker a quick check of the EGC will let you know if it has been bonded at the appliance, either in the receptacle or at the frame of the appliance.**

The bonding jumper at the frame of ranges and dryers are found 6 of 10 evaluations. I have found this defect after the local code enforcement official signed off on the home. Nobody ever looks or makes any attempt to check. In my opinion this is a far bigger hazard than finding a few degrees difference in a two pole breaker supplying one of these appliances.

What about internal contact degradation in the breaker? It will serve to lower the circuit current but increase the internal temperature. This will not be obvious through current draw and visual inspections alone. The terminals will be tight, everything looks fine, and the current draw is at or below nameplate rating. You leave. However, the breaker is still failing.

Thermal-magnetic circuit breakers employ a bi-metallic strip to sense overload conditions. When sufficient overcurrent flows through the circuit breaker’s current path, heat buildup causes the bi-metallic strip to bend. After bending a predetermined distance, the bi-metallic strip makes contact with the tripper bar activating the trip mechanism.
A bi-metallic strip is made of two dissimilar metals bonded together. The two metals have different thermal expansion characteristics, so the bi-metallic strip bends when heated. As current rises, heat also rises.
The hotter the bi-metallic becomes the more it bends. After the source of heat is removed, as when the circuit breaker contacts open, the bi-metallic strip cools and returns to its original condition. This allows a circuit breaker to be manually reset once the overload condition has been corrected.

Now I am going to make an attempt to be funny, can I please, just one time please?
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It must have been a FPE breaker.

I am not a code person I don’t sit around reading a code book my findings are field tested over time my own observations observed over years of IR and electrical. I have focused in on cookstove breakers simply because IMHO they are one of the most highly used higher amperage ampliances in the home and the constance on off expansion/contraction creates loose lugs as you well know. They start with a narrow temp differential and it just increases with time. Most clients never consider having their terminals checked with a given perodicity like they do with having their oil changed in a vehicle. I try to impress them with the need to do this on a given perodicity. It creates work for the electrican and a peace of mind to the home owner. Your giving me the impression that you feel no need for IR I truely hope not we should all be working together not against each other . I do agree that some people do not have the proper training to do electrical IR

You have described the trip mechanism. This is NOT the current carrying contacts. By the way, the bimetalic strips also are subject to heat related stress failure and is denoted by nuissance tripping. The contacts is where the heat is generated when they begin to fail.

I’m not going to pick through this thread (I don’t have the time), but If anyone thinks that this is not a significant issue is so full a **** it’s coming out of their ears!

Do you know what an indirect reading is?

The buzzing sound, is a 6000° arc!

Is that significant enough for you?!

Give me a break!

There is no imbalance of load here.

It doesn’t matter what the amperage draw is.

If you mess with it, you probably will be dead!

It is an electrical connection failure resulting in an arc situation that is conducting enough energy to heat up the electrical conductor downstream of the breaker as well as the breaker.

If I was there, I would shut it off and kept it off.
But there’s a bunch of idiots out there that won’t turn nothing off.

Probably an example of “IR Infrared” training here!

Call it out there Sean!

I’m not going to pick through this thread (I don’t have the time), but If anyone thinks that this is not a significant issue is so full a **** it’s coming out of their ears!

Do you know what an indirect reading is?

The buzzing sound, is a 6000° arc!

Is that significant enough for you?!

Give me a break!

There is no imbalance of load here.

It doesn’t matter what the amperage draw is.

If you mess with it, you probably will be dead!

It is an electrical connection failure resulting in an arc situation that is conducting enough energy to heat up the electrical conductor downstream of the breaker as well as the breaker.

If I was there, I would shut it off and kept it off.
But there’s a bunch of idiots out there that won’t turn nothing off.

Probably an example of “IR Infrared” training here!

Call it out there Sean!

“Recommend further evaluation by a licensed electrician”!?

I have no intention of degrading Mr. Witt or his profession.

But this is a primary example of what I’ve been preaching for years.

It’s one thing when you come up with this recommendation based upon compliance with the standard home inspection standards. But when you get into the infrared thermal imaging and then go about recommending further evaluation by a licensed electrician (as if you were a home inspector), you may as well be recommending the garbage man!

Those of you that do thermal imaging and don’t know how to tell “how hot is too hot” and think that this is not science and there is no necessity to go beyond a $500 training program, this is where thermal imaging increases liability on a home inspector.

This is why this technology was sent back into the dark ages by the veterinarian community.

Everybody has to start out somewhere, but if you’re not dictated to by the federal government to wash your hands after you wipe your *** after you take a ship, would you do it?

If you cannot immediately identify that this particular situation is not catastrophic failure event, maybe you should get on board with someone in another Association such as NACBI where you can discuss these situations without having to listen to morons who support John McKenna and don’t even own a thermal imaging camera!

If you cannot determine what the potential temperature of this component will be if you add full load amperage (without doing it and blowing your face off), should you be doing this ancillary inspection?

If you pull out a $2000 thermal imaging camera, take a $500 training course, find this anomaly and then defer it to an electrician who does not even have a $2000 thermal imaging camera, nor has taken a $500 training course and expect them to follow through with your recommendation, you’re in the land of Oz!

So if a loose connection is to blame who are you going to call to fix it?

Rob
He said he wouldn’t call anyone who didn’t own a $2000 camera

My FLIR T620 had about that much sales tax added when I bought it so I guess I would not be the one.

This was a stove 40 amp breaker that I found on tuesday most electrican would have walked right past it no indication visually there was a problem. Personally I don’t know any electricans that load a panel to check it they do like most HI’s visual only.

So Mr Whitt that means the temp reading on your expensive camera is different than the 2000 Camera ? I feel Flir and Fluke should be correcting that wouldn’t you? The point of this thread A problem was found which may have been missed with out a thermal ,( especially if your hearing was less than good) Buzzing noise was a great indication of a loose connection . The picture confirmed it. I have found several of these even had a sparky say i was full of ****. How ever there was a problem with the main ( he called Later ) to say sorry .
Sean great job keep up the great work .