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How did that even happen..?
For it to get to this point surely you had no protection on it at all. That being both the extension cable and the plug and the breaker??
The heat from the current should have bent the bi-metallic in the breaker. My guy should either buy cable drum with proper quality or check the breaker
in germany power outlets, cable drums and the breaker are usually all rated 16 amps. It would be dangerous to be able to plug things in that can‘t take as much as the breaker
In North America, the breaker protects the wiring and the receptacle. Do you just have 1 receptacle per breaker?
I could probably plug 15 or 16 small led lights into a single circuit and not come close to the max current of a regular residential breaker (15A).
That's why the LEDs lights themselves have thin wires because the expected current is low. While extension cords are really more like an extension to the wiring in your walls and thus should logically handle the same current
You forgot about the part where the consumer buys whatever is cheapest and even big box stores selling shit they shouldn’t to the uninformed public at large
Even with a properly sized extension, it can still melt if it's tight on the spool, the heat is trapped and cause a cascading effect, because the hot wire have higher resistance, which cause more heat.
Not gonna say it cannot be as I'm not an expert, but I think it needs an iron core of sorts to work that way, like a pipe through the middle of the reel.
Also the hot and neutral need separated I think or they cancel out the induction.
RF EE here, this would act like a common-mode choke. What that means is it would behave like an inductor to currents that were of equal magnitude and phase on both conductors since the induced magnetic fields would add together.
But to differential mode currents (currents equal in magnitude but opposite in phase) the magnetic fields would cancel each other out, so it would not have any inductive reactance.
I've never heard it said that way but I will never forget it now.
My brain always knows it as XL=jωL with ω=2πf. But honestly I've not used ω functionally since college.
I used to work with a lot of temp power and got so tired of trying to explain this to people.
Yes, don't do it with the individual feeder runs. Too many people learn that and then assume it must apply to all cable.
There are inductors without magnetic cores.
The current in the wire is what creates the magnetic field. Coils and cores are a means to turn that magnetic field into something with enough strength to actually do something.
Yeah, I'd assume it was a motor load and because of too many extension cords it was getting low voltage. Makes it draw more amps, which reduces voltage more, which makes it draw more amps, which reduces voltage more, and so on and so forth.
True story my wife ran a space heater all night on a 14 100ft coiled up. It was prolly a good hour from turning into this when I found out and unplugged it.
It was solid but gooey. Scared this shit out of me. Shame on me for assuming she knew not
To run it on an random extension cord
Electrical engineer here.
ShortCircuit Protection (SCP) is usually calibrated to only work at Currents (and therefore powers) dictated by a SC happening in the wall socket, a junction box, things that are there by design.
By adding that amount of cable, you also add impedance to the circuit, decreasing the current just enough for it to not be detectable by SCP. The fact that the cable remained coiled added a lot of inductance which also lowered the current just a bit and brought it significantly out of phase.
Extension cables also don't usually have standalone SCP.
I learned this lesson about 17 years ago. Was running temp lights on a commercial site and left 50 feet coiled on the cement floor. If there had been carpet I might still be in prison.
It wasn’t, and I didn’t, but if it had been on carpet and burned down an occupied building and people had died, the da could have pressed charges for manslaughter based on gross negligence.
Ahhh gotya. Yeah that’s a scary fucking thought. I’ve always had older guys yell at me to never leave them coiled in use (never have) and always wondered how accurate they were.
Dang. I'm not an electrician, but this subreddit teaches me something every day. I wouldn't have even thought about making sure extension cords are uncoiled every time.
I watch whole framing squads run off a 16 gauge Christmas cord covered in zip tape with 4 plug strips just murdering their compressors and saws. Noo fks given, just riding that table saw at 3 mph…she’ll warm up in a few…nuts. I just get to run around swapping out melted temp outlets whilst trying to do all the rest.
Hi, weekend warrior here, how many of these would I need for my Olympic sized infinity pool? 760k gallons thanks!
Edit: also, do I need to run water through this or can I throw them in like a cattle trough warmer?
It's essentially like a transformer winding, without the efficiencies of a laminated core so it's open for the magnetic field to escape. It will generate massive heat with current through the winding. This is how tape demagnetisers work, and you can only keep them on for a few 10's of seconds before they overheat. If you add a close core it brings the efficiency back up into the high 90%'s. Anyway, yes, not an electro magnetic as such given it's AC but you get my initial point
Uhm, no... a coiled extension cord is a bifilar winding. The magnetic fields produced by the current running through L and N will cancel each other out.
Only the heat due to the resistance of the cable comes into play here.
If there was a net positive magnetic field, you could use a clamp meter to measure the current running through the cable.
Coiled wire with AC(or pulsed DC) = Inductance which transfers electrical energy into magnetic and back again. The reason it's not a usable electromagnet is there's not a ferrous(or ferromagnetic) core where the flux can concentrate. You can minimize stray inductance in differential pairs by tightly coupling signal pairs, but AC mains Live and Neutral is Single-Ended as the Live carries the sine while neutral is tied to ground and acts as a reference, but is not a current carrier in a properly functioning circuit.
If it was a 4-wire Appliance/HVAC circuit in a split-phase mains then you'd be correct(although there'd still be inductance in that coil as parasitic capacitance and inductance L-L and L-N create unbalanced pairs), as each 120 leg is one half of a center tapped pole pig that are 180° out of phase.
Neutral is absolutely a current carrying conductor in normal 120v household wiring.
If you took your toaster, replaced your neutral wire in the power cable with a multimeter (in current mode), and plugged it in—what would you read?
Or if you’re a fan of current clamps—why can’t I just clamp around romex as is?
> Coiled wire with AC(or pulsed DC) = Inductance which transfers electrical energy into magnetic and back again.
Correct. But look up what a bifilar coil is. That coiled up extension cord is effectively a bifilar coil which results in a net zero magnetic field.
> but AC mains Live and Neutral is Single-Ended as the Live carries the sine while neutral is tied to ground and acts as a reference, but is not a current carrier in a properly functioning circuit.
Uhm, no. neutral carries current, the same amount as on Live, just the other direction. Otherwise the circuit wouldn't work. Assuming your load is between L and N, of course.
Fun fact, if you have a Dyson canister vacuum or in assuming any canister vacuum, and you don't take the cord all the way out and vacuum for a bit of time it will melt the cord.
Oh how I wish I still had the photo, went to a power loss job to an addition the previous professional homeowner did. He was apparently an engineer. He had about a 40ft run for the home run to that addition, he bought a 250ft roll of Romex, uses the 2 ends of the roll, one to drop down the wall, and one to drop to the panel. The other 210ft remained in the roll. Same story though, over time it melted that whole roll of Romex into a solid brick till it finally shorted.
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How did that even happen..? For it to get to this point surely you had no protection on it at all. That being both the extension cable and the plug and the breaker??
This is what happens when you don’t unwrap the cord and leave a continuous max load on it.
No no I get that part 🤣 some serious heat there but why wouldn’t the protection break the circuit at the point where the cables touch?
If the outer jacket material had a lower melting point than the conductor insulation it could melt right off without the insulation being effected
That's the right explanation. It never shorted or went beyond tripping current.
Christmas Light Syndrome
The heat from the current should have bent the bi-metallic in the breaker. My guy should either buy cable drum with proper quality or check the breaker
It never reached the load though. Someone said it down below. 20amp breaker 15 amp load 10 amp cord. Basically
In such a condition the cord becomes the breaker eventually
in germany power outlets, cable drums and the breaker are usually all rated 16 amps. It would be dangerous to be able to plug things in that can‘t take as much as the breaker
In North America, the breaker protects the wiring and the receptacle. Do you just have 1 receptacle per breaker? I could probably plug 15 or 16 small led lights into a single circuit and not come close to the max current of a regular residential breaker (15A).
That's why the LEDs lights themselves have thin wires because the expected current is low. While extension cords are really more like an extension to the wiring in your walls and thus should logically handle the same current
I've seen 12, 14, 16 and 18 awg extension cords. That's not exactly a logical conclusion. They all had 15a plugs.
You forgot about the part where the consumer buys whatever is cheapest and even big box stores selling shit they shouldn’t to the uninformed public at large
Even with a properly sized extension, it can still melt if it's tight on the spool, the heat is trapped and cause a cascading effect, because the hot wire have higher resistance, which cause more heat.
The breaker was sized for the load, cord wasnt
20A circuit, 15A load, 10A cord.
inductance
not here. You have 2 wires with a complete AC circuit in the cord. Fields cancel eachother out.
Toroidal core
Not gonna say it cannot be as I'm not an expert, but I think it needs an iron core of sorts to work that way, like a pipe through the middle of the reel. Also the hot and neutral need separated I think or they cancel out the induction.
RF EE here, this would act like a common-mode choke. What that means is it would behave like an inductor to currents that were of equal magnitude and phase on both conductors since the induced magnetic fields would add together. But to differential mode currents (currents equal in magnitude but opposite in phase) the magnetic fields would cancel each other out, so it would not have any inductive reactance.
My favorite part of inductive reactance is the formula XL=2πFL or "XL = 2 pies for lunch"... Thanks for the reminder.
I've never heard it said that way but I will never forget it now. My brain always knows it as XL=jωL with ω=2πf. But honestly I've not used ω functionally since college.
Very little RF knowledge here, but does your explanation require a resistive load?
I used to work with a lot of temp power and got so tired of trying to explain this to people. Yes, don't do it with the individual feeder runs. Too many people learn that and then assume it must apply to all cable.
There are inductors without magnetic cores. The current in the wire is what creates the magnetic field. Coils and cores are a means to turn that magnetic field into something with enough strength to actually do something.
This is nothing to do with inductance, it’s just a tightly coiled cable set with no way to dissipate the heat being generated.
Never said it did, I was only replying to that person about the cores.
Ah gotcha, there’s been others in the comments saying it’s the inductance, I assumed you were implying the same.
But also low L, which means low X_L, which means low Z, which means high I, which means wire go melty
You don't need a metal core, but in makes it way more efficient.
This was probably hooked to many other cords as well.
Yeah, I'd assume it was a motor load and because of too many extension cords it was getting low voltage. Makes it draw more amps, which reduces voltage more, which makes it draw more amps, which reduces voltage more, and so on and so forth.
The breaker and outlet rated for 20a but the cord only being rated for 15a, being 100'+ long, and being coiled up in the sun?
Probably 16awg cord so not even rated for 15a.
What all were you running constantly to have it at max that long??
Well an air fryer uses like 15 amps at 120v so maybe he was making some nuggies
True story my wife ran a space heater all night on a 14 100ft coiled up. It was prolly a good hour from turning into this when I found out and unplugged it. It was solid but gooey. Scared this shit out of me. Shame on me for assuming she knew not To run it on an random extension cord
Wouldn't there be a significant magenteic field that turns the coils into an induction element?
Eddie currents
Electrical engineer here. ShortCircuit Protection (SCP) is usually calibrated to only work at Currents (and therefore powers) dictated by a SC happening in the wall socket, a junction box, things that are there by design. By adding that amount of cable, you also add impedance to the circuit, decreasing the current just enough for it to not be detectable by SCP. The fact that the cable remained coiled added a lot of inductance which also lowered the current just a bit and brought it significantly out of phase. Extension cables also don't usually have standalone SCP.
I learned this lesson about 17 years ago. Was running temp lights on a commercial site and left 50 feet coiled on the cement floor. If there had been carpet I might still be in prison.
How bad was the outcome that you went to prison??
It wasn’t, and I didn’t, but if it had been on carpet and burned down an occupied building and people had died, the da could have pressed charges for manslaughter based on gross negligence.
Ahhh gotya. Yeah that’s a scary fucking thought. I’ve always had older guys yell at me to never leave them coiled in use (never have) and always wondered how accurate they were.
And I knew better, just from basic electrical theory, I just plain fucked up and spaced it.
Dang. I'm not an electrician, but this subreddit teaches me something every day. I wouldn't have even thought about making sure extension cords are uncoiled every time.
Same
“Don’t act like you’re not impressed”
It’s the pleats in the extension cord. Taking it back to the extension cord store today.
I'd love to see someone bring this in on a shovel or wheelbarrow to a Home Depot and see if they'd exchange it 😂
I just plugged it in and this happened! No idea man!
I've never had an issue with HD swapping out stuff I've burnt up
In a way it worked
This looks like an AI generated photo made to look like it was taken with a phone camera from 2009.
Well, looks like it got hot alright.
Stay in your lane sparky! That's hvac business
I watch whole framing squads run off a 16 gauge Christmas cord covered in zip tape with 4 plug strips just murdering their compressors and saws. Noo fks given, just riding that table saw at 3 mph…she’ll warm up in a few…nuts. I just get to run around swapping out melted temp outlets whilst trying to do all the rest.
And they say American ingenuity is dead.
thats one way to get the copper out of it. edit - please note, do not do this. I was joking. Dun ban me plz.
Hmmmm that gives me an idea
Heater worked.
Hi, weekend warrior here, how many of these would I need for my Olympic sized infinity pool? 760k gallons thanks! Edit: also, do I need to run water through this or can I throw them in like a cattle trough warmer?
Induction heaters are so hot right now
Is... Is that the elephant's foot?
That must be one cheap fucking cord.
Even expensive ones usually have a warning label about unrolling them when used with big loads
So it's like my penis? Thanks everyone, I'll be here all weekend.
Brother made forbidden Salsagheti
Forbidden spaghetti
I'd bet making a heater is probably pretty easy, I'd imagine making a heater that can turn off is more difficult 🤣
Did you just remove the breaker and solder the leads together?!
Titanium bolt fit in there and held
You have a giant spool of wire with electricity running through. It’s creating extra current being left rolled up. Think of how your alternator works.
No shit?
Ohh a big electro magnet....yeah fols, don't do that
It's not a magnet. Since the cable carries N and L, the magnetic fields cancel each other out.
Wow, someone that actually understands theory??
It's essentially like a transformer winding, without the efficiencies of a laminated core so it's open for the magnetic field to escape. It will generate massive heat with current through the winding. This is how tape demagnetisers work, and you can only keep them on for a few 10's of seconds before they overheat. If you add a close core it brings the efficiency back up into the high 90%'s. Anyway, yes, not an electro magnetic as such given it's AC but you get my initial point
Uhm, no... a coiled extension cord is a bifilar winding. The magnetic fields produced by the current running through L and N will cancel each other out. Only the heat due to the resistance of the cable comes into play here. If there was a net positive magnetic field, you could use a clamp meter to measure the current running through the cable.
Err. I disagree. But will leave it there
Coiled wire with AC(or pulsed DC) = Inductance which transfers electrical energy into magnetic and back again. The reason it's not a usable electromagnet is there's not a ferrous(or ferromagnetic) core where the flux can concentrate. You can minimize stray inductance in differential pairs by tightly coupling signal pairs, but AC mains Live and Neutral is Single-Ended as the Live carries the sine while neutral is tied to ground and acts as a reference, but is not a current carrier in a properly functioning circuit. If it was a 4-wire Appliance/HVAC circuit in a split-phase mains then you'd be correct(although there'd still be inductance in that coil as parasitic capacitance and inductance L-L and L-N create unbalanced pairs), as each 120 leg is one half of a center tapped pole pig that are 180° out of phase.
Neutral is absolutely a current carrying conductor in normal 120v household wiring. If you took your toaster, replaced your neutral wire in the power cable with a multimeter (in current mode), and plugged it in—what would you read? Or if you’re a fan of current clamps—why can’t I just clamp around romex as is?
> Coiled wire with AC(or pulsed DC) = Inductance which transfers electrical energy into magnetic and back again. Correct. But look up what a bifilar coil is. That coiled up extension cord is effectively a bifilar coil which results in a net zero magnetic field. > but AC mains Live and Neutral is Single-Ended as the Live carries the sine while neutral is tied to ground and acts as a reference, but is not a current carrier in a properly functioning circuit. Uhm, no. neutral carries current, the same amount as on Live, just the other direction. Otherwise the circuit wouldn't work. Assuming your load is between L and N, of course.
Failed coil
Forbidden doughnut
Fascinating
Salvageable?
Nothing some super 33+ can’t fix 😂😂
pack up
Boss said roll up dude… and he’ll let u know about tomorrow 🤣🤣
success
Aka send pic to manufacture with bill?
Man, this is exactly how I feel after a long week.
This kills the crab.
You made a melter instead!
What was it?
Spaghetti
Fun fact, if you have a Dyson canister vacuum or in assuming any canister vacuum, and you don't take the cord all the way out and vacuum for a bit of time it will melt the cord.
I mean, it clearly heated up ...
Extension cord parmigiana
Looks like it worked!
OP tried to recreate the elephant’s foot
Yeah, 67 amps at 480v with no breaker will do that
How long is (was) this cord?
20a/12ga circuit with an 15a/14ga extension cord
Safety first, roll up extensions to prevent obstructions in walkway floor. Could be a tripping hazard.
Looks like you successfully made a heater, for a little while at least.
I have seen that so many times. Usually, it's near an air compressor.
Watt the hell is that?
It looks like it heated
The Blob!
That's art
My guess would be that it’s not going well.
The big question here is just how powerful was the vacuum you were using.
Mmm forbidden pizza pop filling
You did make an induction heater though
Ohm-an you really did it this time!
I can smell this picture
Success I suppose…
That is some damn good lookin‘ spagett!
That is either an oversized breaker or undersized wire. I expect this from drywallers but not electricians
😂😂😂
Looks like taffy haha
Looks like you succeeded!
This picture is almost older than me
You were successfull.
Freeze it with a fire extinguisher before it consumes everyone. Steve McQueen already solved this one
Oh how I wish I still had the photo, went to a power loss job to an addition the previous professional homeowner did. He was apparently an engineer. He had about a 40ft run for the home run to that addition, he bought a 250ft roll of Romex, uses the 2 ends of the roll, one to drop down the wall, and one to drop to the panel. The other 210ft remained in the roll. Same story though, over time it melted that whole roll of Romex into a solid brick till it finally shorted.
Electricity is funny
Just say it's art, about how our reliance on energy is heating the planet and we need to do something before it catches fire.
Looks like it went well
Phil Swift here for Federal Pacific Breakers….
I just wanna know if it was still passing the current
You have the wrong cord for the amount of current your pulling.
You were 65% successful
That kind of looks tasty
Dumbass
It got hot. Ain’t dumb if it works.
🤣i guess
This is shitposting. Why people doing this so much now? Huh huh huh hilarious. Dummies like you make the job unsafe and make electricians look bad.
Touch on the doll where daddy touched you
Nah dude lol. You are a dumbass for doing this
I agree that op ain’t the brightest for that but laughing at mistakes is hilarious, especially when it wasn’t your mistake .. try laughing a lil dude
This makes other people think it's okay to do kinda dangerous stuff on the job that's my thinking. That's all.