@HappyHemper this is right up your alley 
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Electrical safety is my passion indeed! I shall do this proper. Standby kindly I am a tad bit off kilter and my fingers are too fat to type on the phone. Gonna go find a keyboardā¦
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The heat is generated when the current is forced through a conductor of high resistance. Most commonly, in cases of household appliances, it is because of one of three things:
- Bad connection between the cord end and the wire at the terminals of said plug (series arc)
- Worn-out receptacle, or corrosion on the receptacle (series arc)
- Wire broken, only a few strands holding, at the point where the wire is held for strain relief at the clamp of the cord end (series arc)
ā¦Which is why upstream AFCI devices are now code for most new installations in USA and Canada
If you encounter melting, replace the receptacle, and the plug, and make sure the terminations are done properly.
Assuming the wiring is in spec and there is sufficient voltage/power available to the unit, It is likely that the fans are dirty, bearings shot, or bushings worn. The energy that is meant to move the rotor is then transformed into heat instead of motive force, because the gunk keeps the fan from turning. Remove hair and spider webs from the shaft, rebuild motor, or, more likely, replace the fan. I just turfed one myselfā¦
Your breakers are most likely thermal-magnetic. Which means that heat is used to trip them. The 80% rating is to account for the fact that if it is cold in the space where your breakers are, they will trip at a higher current than if it is warn. So, in theory, you could melt the conductors before the breaker even trips. Extreme example, but happens once in a while. Keep in mind that the breaker is there to only protect the wire. Not your life, not anything else. Oversize the branch circuit wiring, and you could fully load the breaker in a definite-purpose installation. Or you could use a magnetic-hydraulic breaker, in which case temperature is not a concern, but they are expensive and rare.
The ones that plug into the wall outlet. 80% of all electrical fires originate outside of the junction box/wallbox. I would highly recommend everyone use a proper plug, not the injection-molded ones that come melted onto a cable. Cut that shit off, go buy a Leviton or a Hubbell cord-end, and install it properly, clamping the jacket so that it serves as a proper strain relief. Make sure that the cord is in good shape and has no kinks whatsoever, is sized for the ampacity, and keep it nice and dry unless rated otherwise.
Most of the time the culprit is not inside the wall or at the receptacle, but in the cord end or the cable going to the equipment. Take care of your equipment! (especially cords and cord ends).
$0.02 CAD
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Thanks!
Excellent! ā makes me want to rewire everything in my house! 
ā¦whaddabout āannealingā of copper wires?.. 
j/k
gunna run out of electrons soon 
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LOL you can always make more by rubbing a mylar balloon on your head. Unless you have no hair on the head, in which case may have to use hair on other parts of the body, in which case the size of the balloon may need adjustment 
Your comment about copper annealing is well-placed! All copper wire conductors go through resistive heating through a system of energized pulleys after they are drawn. Copper has a benefit of being able to be cooled a little faster than ferrous alloys, so they can do it as they spin it up. Takes about 400C (750F) to get there.
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This is what you are talking about?
Iām getting this.
First Alert ZCOMBO 2-in-1 Smoke Detector & Carbon Monoxide Alarm, Z-Wave Combo Amazon.com
thank you very much for that expert answer!!!
The manufacturer of the fans told the seller that he has over 50% returns or more. The seller couldnāt tell me what exactly was the problem, the seller said maybe something with humidity??? Mine were actually brand new and not dirty, but soon they failed.
You say 80% of all electrical fires originate outside of the junction box/wallbox but in the plug or the cable (You described three cases)
I have some questions about that:
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You wrote something about a series arc. What is that? Is that causing the fire?
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Why are injection molded plugs bad?
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Does that mean it is mostly not the devices which are starting to burn? Do you have more numbers what the causes and locations of electrical fires are?
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How does a bigger fire occur? I was thinking if the plug, the cable or maybe the device are starting to burn the breaker or the rcd will flip and stop the main reason of the fire? Isnāt the plug or the cable made out of non burning materials? So does that mean a fire will start when the cable comes into contact with some other material than the plugs material or the insulation of the cable? Or will the insulation also start to burn?
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sorry but i dont understand what is written in wikipedia 
Can you explain it to me in understandable language?
Very wise topic.
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Agree with the above post. Itās an old thread but there are always new folks coming onboard.
If you are sleeping in the same building as your grow, please make sure to have a plan. Itās well worth reading the posts in this thread.
Iāve got an alarm, an extinguisher, and a fireball above my tent. Be safe!
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Most everything is regulated these days. Unless you got some crazy setup like hardwired directly into the power pole fires are pretty rare. Thermally protected everything is nice in 2023. Circuits and breakers got yah covered pretty good also. So if your light fell or something then for whatever reason didnt kick into protect mode and was directly against something that somehow managed to combust i guess yeah. Led lights thats not really possible and id be hard pressed to even see it with cmh. Maybe hps, mh, etc but even those are thermally protected. Im more worried about passing out with a doobie in my mouth or something
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