Why do electrically shorted components never work again?

[Colt_0pz]

Sounds like a stupid question but i simply don't get it.

[NannerBeans]

The components can get hit with a higher voltage or current than they can handle and die. That said, it's possible something can get shorted and still survive. 

[Nikolithebear]

2 minutes ago, NannerBeans said:

snip

I think he wanted something more in depth.  I was an electrical engineer for about a day... Yeah for a day,  So I'm curious as well! 

[Dormant God]

Yea basicaly what he said but anyway that's why you should be careful when in a storm because it can short your Parts if your not safe but most PSU's have a safeguard but it's proably better to just turn off the computer and take it out from the wall to prevent a short

[it_dont_work]

Multiple factors at play for a few reasons, I can think of two atm 1) voltage or current sensitive components burning out or being irreversibly damaged as they aren't designed to cope with what ends up being supplied to them. 2)  A short jumping current into part of a circuit with the wrong polarity, or from a failed diode.

 

That's a pretty crappy explanation but at least adds a bit of knowledge top the problem.

[Mira Yurizaki]

Electrically shorted components heat up really fast. Then the magic smoke in them pops and escapes. And once the magic smoke escapes, it doesn't come back.

 

... Okay, but the gist of it is electrical shorts cause the part to suck up as much current as it possibly can. This heats up the component until it burns out. Semiconductors are fun, because when they hit a certain temperature, the exhibit thermal runway because their resistance decreases with temperature, making the problem worse. Shorting creates near 0 voltage though.

[Enderman]

That's not true, there are things you can short and they won't get damaged.

But most complicated stuff like motherboards or GPUs and other electronics have a lot of sensitive components that will die when incorrect voltage or current is applied by a short.

[olliestar1129]

Does at least one person know why they do this 

[Mira Yurizaki]

14 minutes ago, olliestar1129 said:

Does at least one person know why they do this 

An electrical short means almost resistance across the input and output power leads of the component. If we break this down into Ohm's Law -> V = IR -> I = V/R... For a very small value of R, you get a huge value in I (or amperes). This means a ton of electric current flows through the part. This causes the conductor to heat up.

 

You ever see what happens to metal when you short a battery?

That's why electronics fail when you short them.

[olliestar1129]

That Is Awesome Thank You Very Much

[olliestar1129]

It is funny because i did not know that would happen

[Thaldor]

And after the component has heated up due shortcircuit or power surge (too much voltage and/or current) damaged components even short or break the circuit. Most usually they break the circuit meaning the electricity cannot flow in it, like a switch in the circuit that has been permanently set to off. More dangerous one is if the damaged component shorts the circuit meaning it doesn't work but lets the power straight through itself, because that way it doesn't comsume current it's supposed to consume and every component after the damaged one is exposed to current higher that they have been designed.

 

As for extra treat there's acctually two kinds of "magic smokes". First one smells like burned plastic and usually means resistor or diode has shorted and got hot enough to burn some circuitboard under it. The second one is the real magic smoke which smells like burned electricity this usually means that some component has blown or capasitor has given its insides out. When you smell the first one you usually find the component quite easily by looking for burn marks and you usually end up changing a lot of components from the circuit since there has been a short and you cannot be sure how many other components were damaged. After smelling the second one you may find some component just plainly exploded or in case of capasitors even one with hole in it's cap or just the whole cap blown away. One big difference between these two is the way they happen, first one is slow usually including flames and smoke for a long period and the second one is fast with a bang. You can do some damage control by the smells, with the second one if you plug the power on usually nothing happens, but with the first one you want to check the circuit throughly before doing anything because the short might have just blown a fuse and when you switch power on, something might go supersonic in the circuit.

[You_are_a_cunt]

Once the magic blue smoke is released, it won't work because it runs on angry pixie dust and magic blue smoke.

 

 

That and all the metal in the component is basically just a blob of molten metal after it burns out

[olliestar1129]

Because of the difference metal wires haven't connected so it stop the electricity going to the right places. Other wise this could happen to it