Slightly OT: bizarre hair dryer repair

Some appliances often suffer that kind of break, push along vacuum cleaners to name just one.

Very unlikely - that would have been a hot spot and the insulation would have been damaged.

More likely a problem where the wire was flexed too often- I usually see these breaks near the strain relief for example.

John :-#)#

I've seen it before. it made no sense to me either. The only thing I could come up with was it crap junk wire and somebody tugged it or tripped on the cord pulling the strands apart.

It might be like a hard disk. they fail just sitting there, but physically destroying one is actually pretty hard when you want to do it.

Electric drills, GHDs to name a couple more. There is seldom any external signs of stress at the point where the break has occured. In my experience, hairdryers are one of the more common items to suffer from this.

Arfa

Cables do break like this, have seen it before. Usually metal fatigue from flexing. Metal fatigue will happen in a LOT less number of flexes than PVC insulation "fatigue".

On the other hand, it is possible that there was some kind of break, weak point or many strands were broken in manufacturing, or some other weird thing happened on the assembly line but this would likely cause arcing and visible heat stress to the cable such as blackening on the inside and melting- especially with something that pulls a few amps like a hair dryer ?

(...)

At my previous job, the lab manager would pull on DMM test leads until the wire inside broke. The silicone insulation looked just fine to the naked eye and the broken probes would yield intermittent and / or nonsense readings.

--Winston