A number of AC power cords on Ebay seem to be miswired

[SeanB]

Miswired cords are pretty common, and here in S Africa the installation of a ground fault breaker is mandatory on all legal installations.

http://mybroadband.co.za/news/energy/116854-this-is-how-people-steal-electricity-in-south-africa.html

Not on these though.............. I have driven over the cables laid on the main road near an "informal settlement" on a few occasions, and even if I wound one around a wheel I would not stop until I was well away.

[Tinkerer]

If you recently bought a cheap 3-prong power cord, or an appliance of questionable quality that included such a cable, you may want to check that it is wired properly. The right pin (with plug facing away) should be connected to the female pin labeled L (for live).

Not just recently. Back in the middle of 2013 I bought a cheap power cord off ebay so I could have a spare to use with something. I ended up using it a couple times and thats it.(it wasnt connected for long either time)(I wasnt working at the time, couldnt spend tons of money)
The cord says rated for 10A 250V, this is definitly wrong. The cord is thinner compared with a 10A 125V rated cord that I use for my computer. When I got the cord, I realized it was thinner but figured I didnt really care because I was going to be using it under an amp.
As it turns out, the polarity is also reversed in this one. Upon measuring it(just a few minutes ago), it also has the increased resistance of something like 1.1?.(I did take into account my test leads) Also, upon double checking my measurements, the thing was so shoddy that one of the female terminals broke. Glad I didnt use this much.
Guess I should buy a real one now.

So, recently? Not so much, there must be at least 1000s of these cord floating around out there now in the US. And they have been out there for a couple years at least. So, I would avoid buying any cords from china/ebay unless you are certain they are made properly.

[jaxbird]

I recently had a cheap chinese power cable produce something like a 100mm flame just 300mm from my leg. Pretty scary.

Not sure exactly what caused it (besides it obviously shorted inside), On closer inspection the cable looked pretty beefy on the outside, but cutting it up and looking closer I'm sure it was 99% plastic/rubber, the actual conductors were unbelievably thin.

I believe the insulation of individual wires was random and close to near short at multiple points and probably the insulation made of a material melting at a low temperature.

Life is already too short, no need to shorten it further using the cheapest and worst products coming out of China just to save a few $.

[cosmicray]

Ebay listing:

http://www.ebay.com/itm/111424284330

About $2.50 shipped, 448 already sold!

That eBay listing says the item is located in the US. How they can receive that minimal amount, pay the PP fee, the eBay final value fee, and still have anything left to pay USPS eludes me. Perhaps these were known defective, and someone dumped them into eBay to get rid of them ? CPSC might be interested in these test results.


http://www.cpsc.gov/

[ciccio]

Here in Italy (unfortunately) the standard plug is non polarized (there are two types, 10A similar to the two pin "Europlug CEE7/16" but with central earth pin and a larger 16 A type).
So a reversed wire in a power cable will not be detected. Equipment design must take this into consideration.
The problem with these cheap cables is the copper section: it's so small that you will run into problems.
Once I bough a replacement PC power supply. The box contained a new power cable, that I did not use. It was clearly labeled 250V/10A  3x0.75 mm2. 
After some time I decided to use it (it was sitting in the lab shelves) to test a 1000 W audio amplifier.
In less than one minute it started to smell, in two minutes it burst into flames. The bench surface has a charred area, where the cable was sitting.
I looked at the copper: it was about 0.22 mm2.
I contacted the supplier of the power supply: they answered that the cable was obviously only suitable for the 400 W supply with which it was sold, and it was not intended for other uses.... I responded saying that I was going to change supplier, and I did.
Best regards

[donmr]

Looks like a typical low power cord. The problem with the advert is that it doesn't say it is low power and not for use with a kettle...

It still needs to handle at least as much current as the breaker or fuse on the supply system. Here in the US the minimum breaker for home wiring is 15A.  Anything plugged into a 15A circuit must be safe up to that current. 

People often get this backwards, the breaker needs to be the weakest link in the chain so it will trip before anything else starts burning.

Don

[rickselectricalprojects]

ANOTHER WARNING!!!
if you but anything of ebay that is prewired ALWAYS ALWAYS ALWAYS!!! check to see if it is wired properly. I had an experience once were I brought two led switch mode power supplies of ebay and the had the live wire screwed into the earth terminal on both the power supplies and I was lucky that I didn't shock myself.

[amyk]

Another reason to get an x-ray machine...?

[suicidaleggroll]

Another reason to not buy bargain basement knockoff shit on eBay?

I mean seriously, what do you expect?  Do you honestly expect to pay 2 cents on the dollar for a power delivery product that's not going to light your house on fire and burn you alive?  Because if so, you're sadly mistaken.  These people don't care about you, they don't care about your safety, they don't care about how many people their products kill.  They're no different than the scam artists selling knockoff phone chargers on the street corner that will electrocute you if the humidity in the room gets too high.

If you value your life or the lives of those near you, stop supporting these people and stop buying 10 cent shit on eBay.

[jbryan2]

I've cut the cable apart and the wires are microscopic as expected. Not sure if it is 28 awg but something in that vicinity. Resistance of a 50 cm length of wire was 0.5 ohm (with a zeroed out meter).

The cable is marked as

PVC YOUZHI DIANXIAN 227 53 (RVV) 300/500V

Ebay listing:

http://www.ebay.com/itm/111424284330

About $2.50 shipped, 448 already sold!

I can't remember where I read about these counterfeit "power" cables, it's been so long.  Copper is expensive.  Did the cord even match the picture, or did they skimp on the insulation too?  Counterfeiting is a major industry in China, and they are taking every opportunity to pass off cheap materials for the real thing.

Bargain hunters aren't exclusive to eBay.  Counterfeit high-strength fasteners have already killed a lot of people because the fakes are almost impossible to identify without 100% testing.  They're even being discovered in the aircraft and military supply chains.  The defense industry is a particular target for counterfeit components not just because the potential profit is huge, but for other obvious reasons as well.

You could be a good citizen and report it, give negative feedback on the seller (though they're probably spoofing their "99%" rating too), consider yourself educated, and buy from reputable suppliers from now on.

It's bad enough when somebody cuts corners and burns their own house down. It's particularly tragic when your product burns somebody else's house down.

[Corporate666]

Another reason to not buy bargain basement knockoff shit on eBay?

I mean seriously, what do you expect?  Do you honestly expect to pay 2 cents on the dollar for a power delivery product that's not going to light your house on fire and burn you alive?  Because if so, you're sadly mistaken.  These people don't care about you, they don't care about your safety, they don't care about how many people their products kill.  They're no different than the scam artists selling knockoff phone chargers on the street corner that will electrocute you if the humidity in the room gets too high.

If you value your life or the lives of those near you, stop supporting these people and stop buying 10 cent shit on eBay.

Well said

There is a Youtube channel I came across of a guy (this one is in the UK but could be anywhere) that buys cheap shit on eBay and makes rant videos about how the parts he got are junk and he can't use them in his (commercial) projects because they will fail. 

He will buy 10 wall adapter power supplies for $5... or 500 1-watt LED's for $20... then go on an angry rant that such-and-such eBayer screwed him over because the LED's have a green tint and he can't use them as medical light replacements, or the wall adapters have tons of ripple or they fall out of the wall sockets and his customers are getting upset.

And all I can think is... you dumb cheap bastard.... stop buying shit and thinking it should be top shelf stuff.  And definitely don't keep doing it and blaming the sellers.

No offense to the OP - I am not saying he's doing this, it just reminded me of the Youtube dope.

[TMM]

People buy IEC power cords? Every proper geek should have about 50 of them from PC monitors and powersupplies over the years. At least when they come with a reputable brand 400W+ powersupply you know it's wired properly and has appropriately sized wiring.

[Artlav]

Can it be that you feel this way about reverse polarity because you live in countries with 220V outlets where both wires are energized?

Not exactly - in (most?) native 220V countries there is a live 220V wire and a neutral wire, not two different phase live wires like in USA.
However, here you make no assumptions about which is live and which is neutral, so by all intents and purposes there are two live wires - a polarized mains plug is kind of peculiar to look at.

Not all equipment is designed with that in mind - on at least one occasion i had to flip a plug to stop a PC case from giving "static" shocks to people.
But i never seen a fuse being present on both conductors.

if you but anything of ebay that is prewired ALWAYS ALWAYS ALWAYS!!! check to see if it is wired properly.

Don't turn it on, take it apart! (and check everything)

[tszaboo]

However, here you make no assumptions about which is live and which is neutral, so by all intents and purposes there are two live wires - a polarized mains plug is kind of peculiar to look at.

Exactly. The german schuko conenctor doesnt specify the polarity, plugs can be inserted either way. Coincidently, this is the best connector for mains. If any device relies on the IEC connector, the electrical designer has no clue about safety. So the cable polarity mostly does not matter, unless if you mix earth and neutral.
This is no excuse of course for the tiny conductor inside.

[coppice]

Not exactly - in (most?) native 220V countries there is a live 220V wire and a neutral wire, not two different phase live wires like in USA.

There is at least one country where the normal domestic and commercial delivery of power is 220V with the legs balanced about earth - the Philippines. This is like 220V power in the US, but in the US its a special case for high consumption appliances, while in the Philippines its what all appliances use. I think this comes from a historical position, where the country once used 110V power, but I am not sure.