This may seem like a dumb question to some, but I need some help.
During a recent inspection, I pointed out a higher than normal temperature reading of an electrical panel component (6 AWG wire, 30 amp Pushmatic breaker for an electric range/oven). The temperature at the lug was 170 degrees. I know some wires can be rated to be higher than this, but it seems outside the norm to me. They had another inspection two months ago, and the other inspector is saying that it’s safe and normal. I just said they need to have the panel evaluated and corrected as needed by a licensed electrical contractor. Can anyone point me in the right direction? Yes the range was on when i scanned the panel.
So 2 mnths ago I had a physical AND the doctor said my BP was normal, BUT yesterday at the other clinic they said my BP was high and recommended further evaluation.
And what was the comparative information at the time of the previous inspection, and was the other inspectors test method(s) the same, with equally calibrated EQ and functional training?
Did you use your Flir for observations of the panel from multiple angles? Did you adjust for reflectivity or emissivity of the lug? What was ambient temperature?
The other inspector’s opinions are likely based on different circumstances.
Having said all that, your photo does not show something that rates concern. Your photo indicates only 100F above the lowest temp in the photo that may be close to ambient temperature.
Correct. No problem with the size of conductor. More of an issue with the electric range. Unless it’s a very small one, or the breaker wasn’t labeled correctly.
The panel is located in the dark closet with no light/ambient reflection. The temperature was 170 degrees, and yes, the scan was of multiple angles and various readings. While the temperature rose.
I’ve taken scans of multiple panels while testing the electrical range, and only a few reached above 160. I know things change from one inspection to the next, that’s why I wouldn’t tell the agents that the other inspector did something wrong or that he doesn’t know what he’s doing. All I wrote up is that it warrants evaluation by a licensed electrician since it’s in a closet, it’s Pushmatic, it has overspray, and elevated temperatures.
I pointed out a higher than normal temperature reading of an electrical panel component (6 AWG wire, 30 amp Pushmatic breaker for an electric range/oven). The temperature at the lug was 170 degrees
There is some problem with this. I would assume that the oven was on during your test. Did you take an amp reading on the conductor in question?
I’ll over-simplify, but your IR doesn’t care about light/ambient reflection because it is a dark closet. It is the same for the IR in a well lit closet.
It is popular to use IR on the service panels, but few inspectors go to the trouble to understand what their IR is showing them. 100F above ambient is typically not a concern.
Consider this:
Glad to hear that. I ran into something similar to the OP. This was the neutral (grounded conductor) at the main lug on a subpanel within a large workshop with mini-split air conditioner running.
The owner was experiencing high electrical bills and was glad that I might have found a possible cause. Although I just reported the warm temperature, I suspected that the lug connection was loose and could be arcing.
So what are you measuring here? 6AWG wire, the breaker, or the lug?
What emissivity did you adjust for? They all have a different emissivity.
What was your Temp Reflect setting? They all have a different IR Reflect.
What is the temperature capacity of the three items? You’re making a call based on temperature rise, so what is the threshold?
Well, did you?
If it is this hot with only 2 amps drawing, what is the calculated apparent temperature rise if you were to add the other 28 Amps? This is a calculation you should know if you are going to talk about too much temperature. Would this not be a significant consideration?
Are you sure? Did you ever point your camera at a high reflective surface and see a hot lens in the scan, you know there is a heater in the camera to raise it above a needed ambient? Your terminology may be incorrect, but where energy comes from is critical to know.
And why would you be commenting on what the other inspector reported? Do you know how he arrived at his conclusion? I’m not sure if you know how to come up with your own conclusion at this point.
You wrote up for an electrician to evaluate what you saw thermally. How the hell are they going to address your thermal data when that is not their job? They are not Thermographers. If you are going to pull out an IR where the MSX can’t even line up with the components, and without MSX, you can’t identify anything but blobs, how do you expect them to come up with anything?
I can’t even make a SWAG about the data you provided. But I can look at the thermal gradient and see that there are two potential sources of heat. The appliance load (which we didn’t take amperage measurements) and resistance load between the conductor and lug connection.
Conclusion: nothing to see here. There is heat above the connection around the main buss connections. Is that heat coming from or going to the buss? One way it will increase the lug temp, and the other way it will cool it. Both create an error.
See that 70/164 gradient on the right? That is what the wires would look like if there is a connection problem (indicating conductive heat transfer).
You don’t take a measurement of the hottest object in the scan and try to use it without bothering to calculate from an “Apparent” measurement, to an absolute measurement. Where you have your spot measurement tool, there is something else going on because of the reflection of the geometry. An Alu electrical lug can have an emissivity around 20% (depending on surface condition). But because of geometric reflections in the IR spectrum, it could be as close to 100% as any material in the scan. If you’re going to play with temperature readings, you best be able to calculate this, or stick with “apparent” measurements and setting your emissivity to 100%. Guessing at emissivity will come back and bite you. Changing emissivity to display a higher temp, or placing the measurement tool on a reflection, can and will be construed is you trying to make a bigger issue than what is there.
Use the IR as a glorified flashlight, find potential and further evaluation what is going on. Don’t defer to an electrician because in most cases they don’t know better either. If you can’t figure it out through normal HI Standard, keep your mouth shut because you are not qualified.
Since this is a 240 volt range the load on each leg should be just about the same. Did you test the other leg as well? Was the temperature about the same on both legs?
Dave just gave a free primer on IR above. There may be some offended folks reading his comments. Years ago, I posted a similar photo on InspectionNews and got my head handed to me by some inspector in NJ. Instead of taking offense from her put down, I spent the money and time, and got some training…nowhere close to Dave’s training but enough to guide me on limiting my opinions based on my IR observations.
I constantly see IR photos here with opinions that should not be made based on the photos. Most inspectors do not use their IR correctly and draw inaccurate conclusions. But since most other people in the trades don’t know any better, we get away with it… most of the time. But it is something like tossing darts blind folded. Just because you hit the target sometimes doesn’t mean you should be throwing darts blind folded.
Francisco…Several times I typed that your photo shows that you need training in using IR, but I erased that sentence because it’s hard to say that without sounding like I am insulting you. I really don’t mean to insult you or anyone who thinks they are doing something good by simply pointing their IR at a service panel. Go get some good training and I think that you will, like I did years ago, appreciate someone like Dave admonishing you.
What’s more sensitive, thermal cameras, or thermal camera experts?
Ribbing aside, the respondents have a point here. Unless I plan to become fully versed in all of the settings and readings of an IR camera, I’m only going to use it as a set of eyes, not as a measuring device or conclusive diagnostic tool. So the wire was hot - that’s good to know, but at that point I’d put down the camera. Maybe pull an amp measurement if you’re comfortable presenting those findings or doing something with them, or with the breaker off check for loose connections at both ends. I recently fixed an electric range draw problem at my daughter’s house by zeroing in on the problem using my inferior quality thermal cam, then tracing it back to loose contact points. So yeah, a thermal camera can be used casually, but not conclusively.
I barely have the time to lay out the facts of the issue, never mind make everyone walking around with a noose around their neck feel comfortable with themselves.
If you are new here, please be aware that my responses are more for the readers out there than the OP. I don’t care if I upset the OP, they are just one person doing wrong that will likely never change. But it is critical to all the people here that come to learn stuff, that they do not adopt incorrect information and apply it to their business plan. So this thread is for all of you, not so much the OP.
You are correct that this is an issue, regardless of the scan quality.
Grounded and grounding conductors do often show up hot. Many feel there is no real power running through a grounded conductor, but they burn up just a phase conductor. And yes, they are dangerous.
Please note that your spot meter has a cold wire passing through it.
It remeasures 101F, but the closer apparent temperature is closer to the 147F on the temp scale (depending on the camera setting). So reporting a warmer temp on a grounded conductor may be an understatement.
Because this is an indirect temperature measurement, you could be having a 7k F arc going on there, even at these low temp readings.
