# USB cable melted



## gregzoll (Dec 25, 2006)

Forgot the how and why. Toss the charger & cable, and go get a new one.


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## de-nagorg (Feb 23, 2014)

Wires usually melt for one of two reasons, either too much amperage running through them, or too close to an external heat source. 

Only you know for sure if either had happened. And either way I would just replace the melted USB and use the others. 


ED


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## dmxtothemax (Oct 26, 2010)

It is very unlikely that a faulty usb lead would cause
The other equipment to become unsafe !
If it looks ok ? Use it !


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## curiousB (Jan 16, 2012)

adamchrissy said:


> A USB lead I was using to charge my mobile phone melted. The lead was plugged into a USB wall charger which in turn was plugged into an extension lead and into the wall socket. The only damage was to the USB lead. The phones charging function, the extension lead, USB wall charger and the wall socket itself are all still working and there is no sign of damage. Is it safe to continue using them? or Is it possible that one of them caused the USB lead to overheat and melt? and/or Could the overheating of the lead have caused any or all the following to have become unsafe? : the Mobile itself, the extension lead, the wall charger, and the wall socket


I suspect USB cable was manufactured improperly or more likely got frayed inside at a bend point. As the cable frays fewer conductors are left to carry the current thus they heat up.


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## Run and find ou (Jul 5, 2014)

Melted in the middle, or are there signs of overheating at the ends? I've seen electricians prescribe replacing everything at the scene of an overheating incident, on the theory that insulation and contacts will have deteriorated as a result, but I don't know whether it's necessary.


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## adamchrissy (Sep 6, 2014)

Thanks for the replies 
Run and find ou - It was the middle of the lead that melted. Both ends of the lead appear fine (thats not to say the wire inside the entire length of the lead had not also been damaged)and the micro USB and the standard USB connectors at each end also look fine and unaffected.


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## r0ckstarr (Jan 8, 2013)

Any chance this was a Samsung phone/charger?


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## adamchrissy (Sep 6, 2014)

r0ckstarr : It was a Alcatel phone, and a Camelion USB power supply adapter


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## adamchrissy (Sep 6, 2014)

The adapter I was using supplies 5V and 2A when charging one item (it has a total of 4 USB inputs) The phone required input is 5v and 550mA. Could this be the reason for the overheating? - I thought it was possible to use a charger that at least supplies the required input of a particular item you wish to charge and having more then the required amount did not matter - is this correct?


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## gregzoll (Dec 25, 2006)

adamchrissy said:


> The adapter I was using supplies 5V and 2A when charging one item (it has a total of 4 USB inputs) The phone required input is 5v and 550mA. Could this be the reason for the overheating? - I thought it was possible to use a charger that at least supplies the required input of a particular item you wish to charge and having more then the required amount did not matter - is this correct?


Faulty charger, that caused the cable to melt. Call yourself lucky that it did not damage your phone.

No need to dissect the why & how it happened. BTW, where did you purchase this adapter, and how long have you had it?

It is possible that a short happened on one end of the plug, and caused the overheating at a part of the cable, that had been damaged.


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## McSteve (Dec 8, 2009)

So many cheap USB cables these days have "wires" that are practically made out of foil. Like headphone wires; just a strip of foil wound around a thread.


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## digitalplumber (Jul 8, 2011)

Yep apple had a story recently about 3rd party wires causing issues with their phones.


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## gregzoll (Dec 25, 2006)

digitalplumber said:


> Yep apple had a story recently about 3rd party wires causing issues with their phones.


That was an issue with UK citizens using Cheap Chinese knock-offs.


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## digitalplumber (Jul 8, 2011)

gregzoll said:


> That was an issue with UK citizens using Cheap Chinese knock-offs.


Oh that's right, we don't get any of that stuff off of eBay in the States! :thumbsup:


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## gary300 (Mar 28, 2014)

Wiring in USB cables is very thin and if any short occurs (any damage to the cable that would cause the insulation to separate in the cable and let the wires touch) the wire will act like a fuse and just melt, especially if you using a charger that can supply 2 amps. 2 amps times 5 volts is 10 Watts and if that is concentrated in a small space it can produce a lot of heat at the location of the short.

The charger is not the culprit here. Just replace the cable and you are fine.


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## petey_c (Jul 25, 2008)

A little case for arc fault breakers? Hot enough to melt insulation (not that it has to that hot), but not enough current to trip the breaker.


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## Oso954 (Jun 23, 2012)

> A little case for arc fault breakers?


How to you expect the arc fault to see thru the charger that has roughly a 24 to 1 voltage reduction ???

How big of an arc do you expect at 5 volts ?


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## petey_c (Jul 25, 2008)

Oso, That may not reach the threshold for an AFCI, but it's a good analogy for when people complain about the need for an AFCI. That was what I was trying to illustrate.


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