The Shanghai Cable Guy and the Future of Chinese Quality

The other night I was startled by the smell of burnt rubber wafting into my living room. I immediately went sniffing for the source, and after a very brief search I noticed smoke coming from the electrical socket connected to the space heater in my bedroom. The cable was hot as I pulled it from the wall, and when I looked at the plug, this is what I found:


[I’ve blacked out information that identifies the manufacturer]

I’m no electrician, but I know a defective plug and cable when I smell one. More likely than not, some impurity in the copper used to manufacture the cable or plug raised the electrical resistance so that it began to overheat (and yes, I tried a different appliance in the outlet – and there was no problem).

As it happens, three weeks before this near-death experience, I attended (and addressed) a recycling conference in Guangzhou. Among the speakers was Huang Chongqi, deputy chief engineer with the Shanghai Electric Cable Institute. Now, that didn’t sound exciting to me, either, but one never knows, and so I decided to listen to the introduction and then go from there. I ended up listening to the entire presentation and, as a result, I preemptively understood why my space heater nearly killed me, and why I – and many others – will continue to be threatened by Chinese manufactured space heaters (or, at least, the sub-contracted cables and plugs attached to them) for years to come … explanation after the jump.

Here’s the first problem: China’s manufacturing sector requires vast amounts of copper (anything electrical …), but China lacks sufficient copper resources to meed the demand. As a result, China has a large secondary copper industry that produces copper products – such as cables – from scrap metal. No good statistics exist on the exact volumes, but Mr. Huang estimates that China manufactures roughly 1.8 million metric tons of cable from scrap metal every year (roughly 50% of China’s total cable production). On balance, secondary copper is good for the environment, and China recycles lots of it [Below, one of the world’s largest copper scrap processing centers, in Taizhou, Zhejiang Province].


But here’s the second problem: it isn’t easy – technically – to take a mixed batch of scrap copper and re-melt it into a material that meets international electrical resistance standards (we’re talking purities on the order of 99.9%). To be sure, the technology exists, but it’s expensive and rarely utilized in China (according to Mr. Huang). At the same time, entry barriers are minimal and cheap if you’d like to set up a re-melting facility that makes, say, 99.5% purity copper – even though such copper doesn’t meet international standards. Not only that, China’s growing appetite for copper cable pretty much guarantees that your non-standard cable will have a ready market. The result, according to Mr. Huang, is that “product quality is out of control.” Below, a secondary copper wire manufacturing facility in Guangdong:


Mr. Huang has spent a significant amount of time investigating actual copper factories, and the results are not pretty. “Most of them have no or imperfect chemical analysis components … some of them don’t even have a single piece of equipment devoted to quality inspection.” And then he gets specific:

  • In Guangdong Province, 80% of the wire/cable products are “unqualified,” of which 46.9% don’t meet the standard electrical resistance index;
  • In Hunan Province, the unqualified rate of wire/cable products is 34.6%. Among the 35 unqualified wire/cable products sampled, 25 are unqualified because of resistance exceeding the standard;
  • In Zhejiang Province, the unqualified rate of wire and cable exceeds 60%.

[A print version of Huang’s speech was distributed at the conference, complete with citations for these figures.]

The most “dreadful” consequences of faulty electrical products are wasted electricity and heightened fire risk, and they can be expected to impact “hundreds of millions of households” in the long-term – according to Mr. Huang. As it happens, my defective space heater was manufactured by a state-owned company in Zhejiang, and the defective cable was made by a sub-contractor in Ningbo (the name is printed on the cable and the plug) And Ningbo is one of China’s leading copper scrap recycling centers (most of the scrap is imported). I should acknowledge that the actual copper may have been manufactured at another factory – though it was almost certainly manufactured in the Ningbo area.

Mr. Huang was not positive about the prospects for solving this problem. As he noted throughout his speech, China’s electrical cable industry is large and profitable – in spite of the fact that it’s technologically backward. And really, there’s no reason to believe that the industry could become more profitable if the technology – and thus, the quality – were improved. After all, the industry is growing while it manufactures sub-standard goods.

That is, this situation will persist.

Huang, in his conclusion, was left with no choice but to encourage better “state policies” and technology. As a final, parting gesture, addressed the electrical products manufacturers themselves: “[O]ur entrepreneurs should strive to improve themselves in development, and self-discipline in quality.”

I hope it works out. In the meantime, I’m looking for a space heater with a cord manufactured outside of China.

6 thoughts on “The Shanghai Cable Guy and the Future of Chinese Quality

  1. One possible culprit is aluminum. Although a relatively good conductor of electricity, it has some characteristics that allow a high resistance interface oxide layer (IIRC) to establish itself where it makes contact with other metal surfaces, even ones that are also aluminum. There was a brief period in the late 60s and early 70s when the National Electrical Code allowed a type of aluminum wiring to be used in residences in the USA, but that lasted only a couple of years because of the incidence of fires. Early in our marriage, my wife and I lived in a apartment in southeast Pennsylvania built during that era, and one day (fortunately not night) we smelled smoke which we finally traced to be coming from inside an outlet. We tripped the breaker and called maintenance, and they fixed it. A few months later there was a fire in a building across the green that killed a man in his 80s who was visiting one of his children, who lived there. At the time I was unfamiliar with the NEC and the various issues involved in it. As I became familiar with it in my work in subsequent years, especially as regards the issue, I’ve wondered if that was the underlying cause of those fires.

    PS: Hello from Minnetonka! I believe one of my daughters knew you at HHS, perhaps from debate team adventures.

  2. Time to think about buying Made In China electrical appliances with wire. Do they use local stuff in their electronic goods too ? Is that why cellphones batteries explode ?

  3. Larry – They do use local stuff in their goods, though it’s worth recalling that only half of China’s copper supply is secondary. The rest is primary and presumably of better quality. Beyond space heaters, though, I’ve really no insights on this matter.

  4. The problem is likely caused by a brief surge in the Voltage which can generate more heat than the circuit is designed to handle. Substandard copper may not be the cause since more electrical resistance means less current and thus less power and heat.

  5. MC – Thanks for your comment. For some reason, it was caught in my comment spam filter, and didn’t post right away. Anyway, I’m glad I caught it, because you clearly know more about the subject of electrical resistance and its effects than I do! Thanks much for the comment, and I will take it into account when I write about the quality issue in the future.

  6. Great piece. I know nothing about resistance, but regarding impurities I’ve been told that oxygen is the main impurity that keeps China’s secondary copper from meeting international standards. Oxygen creates microscopic bubbles in the copper, making it brittle. Not sure if that can lead to fried cables though.

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