One of my Haozee power plugs (Neo Electronics NAS-WR01ZE) that I’ve been using to monitor computer equipment power but more recently my 120v electric car charging which draws just under 12 amps now looks like this…
I just read the specs for the device…
It managed to survive almost 250 hours of monitoring my car charging @ 11.5 amps…
Make sure you read and heed manufacturer’s specs!
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Welp. That’s what you get from ccc (cheap chinese crap). A few bucks saved and the house burnt down… At least you were lucky and it didn’t do more damage.
That thing was supposedly rated at 10A continuous and you overloaded it by 15%. Which, while not a good idea as you said yourself, should not cause a catastrophic failure like that. That should never happen with small overloads like this. Quality and certified (is that thing even UL listed ?) devices have rather large security margins and overheat protections to prevent that. I wouldn’t trust a device like that even at its own ‘officially’ rated max current. I wouldn’t trust a device like that with anything more than a few LED lights on it.
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omg that’s scary indeed
Uncertified electrical device is operated near or above its self-certified operating specs. What could go wrong? 
Nasty but predictable. Not nearly as surprisingly catastrophic as some of the posts on r/whatcouldgowrong.
(Shorted lithium batteries are hellish devices.)
Soo easy to say, what’s not a ‘ccc’ plug? Isn’t most of the electronics nowadays coming from China?
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It’s not the fact that it was manufactured there. It’s the fact that it’s direct import stuff from a Chinese company that does not follow international standards and certifications and is not legally liable for any damages their stuff does. So basically they can get away with pretty much anything and just sell the cheapest crap they can turn out. These kind of products often use electronic components that failed QA control from the production lines that actually produce the stuff for the more reputable manufacturers. Or they just use counterfeit ones.
This is not direct import is it? This is just an example out of MANY of these types of plugs on ANY
European webshop.
These plugs are all spin offs of each other and brands like gosund, shelly and the likes of zwave and zigbee are just built around the same components?
Even an iPhone can burn like hell doesn’t it?
My point being, does it really matter how it was imported? It matters if something was reliably built. And these neo coolcam stuff seems to be reliably built.
I wonder what happened to the OP plug outlet… I have a few of thos spin offs (bought via EU webshop - amazon)
Actually it is. Amazon is notorious for either doing drop shipping (which is 100% direct import) or they just provide storage facilities and logistics for webshops doing direct import. Amazon does in no way guarantee that the product is safe or follows local electrical code. Now IANAL, but legally this is probably gray area. Few people would sue someone like Amazon over it though… Any importer, may it be a webshop or your local HomeDepot/clone is technically responsible for guaranteeing safety and standards of the product it sells. It doesn’t always mean they do though.
Not really. There can be significant differences in the components used, their quality (not always visible from the component alone) and PCB layouts used. In the case of Zwave and Zigbee, the RF chips are probably the same. But that’s where similarities end. Here’s an interesting comparison between the UL and non-UL listed Sonoffs. Sometimes the differences may seem minor, but they can make the difference between a thermal fuse tripping and the house catching fire.
Shelly is not a Chinese company btw.
Yeah. So could the Galaxy Note 7’s. Remember those ? This stuff cost Samsung a lot of money in legal fallout, reputation loss, etc. They put a lot of energy into finding out what happened, why and how to avoid this in the future. And that’s the point here. If something like that happens to a reputable manufacturer, there will be financial and legal consequences. In gross negligence scenarios, people can go to jail for these things. That does not apply to Chinese manufacturers, unless they do so much local damage that the CCP steps in. But besides that, as a Westerner, you cannot sue a Chinese company. They know that.
It’s not. It burned up. That’s not supposed to happen under the circumstances the OP described with a well designed and protected device.
Pretty obvious what happened. I’ll quote Taras above:
I blame myself for not referring to and heeding manufacturer’s specs. It and many others I now see are rated for 10 amps continuous load even though the technical parameters states Max current 13A which is what I was going by. I was running it at 11.5 amps and it worked fine for about 250 hours when it failed. There are two z-wave parameters involved:
3. Configure maximum over-load current: available settings: 1-16 amps, default 13.
4. Configure maximum Alarm current: available settings: 1 to Parameter #3, default 12.
These obviously are meant for the Instantaneous load current since 16A max is the instantaneous load current. 10A max is the Continuous load current. I have two more of these in service, one on my washing machine and one on my coffee maker. Washing machine spin cycle is 6.5 to 7 amps. Coffee maker is 5.9 amps when brewing. I’ve set parameter 3 on those to 9A and parameter 4 to 8A but am considering pulling them from service.
The receptacle is a little damaged as is the cover plate. About 6 sq in of drywall surface has lifted and after a good cleaning with TSP a lot of the black soot has come off.
Normally for electrical outlets, the safest continuous current would be 80% of the rated value.
We call it “Derating the outlets”. This is common practice at my workplace.
I appreciate you sharing this, including the detailed photos. It may well save someone’s life, or at least their home.
That is not correct. Outlets in north america are rated at 100% of their loads. Some electrical breakers are rated at 80% of their loads, but this is mostly not the case anymore with modern breakers.
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The manufacturer’s specs aren’t vetted by anyone so consider them to be more of a ‘perfect world’ promise as opposed to a ‘real world’ guarantee. Without an independent party subjecting the device to a range of standardized tests, and determining if it qualifies for industry-recognized certification, you get what you got.
Fact is, what standards bodies like UL, ETL, CSA, etc do is more than “confirm the device does what it promises” but does it fail gracefully, and safely, when abused. A thermal fuse should have disconnected the mains well before a component ignited but that costs extra and the manufacturer’s penny-pinching design just lets the device self-destruct.
FWIW, I own over a dozen WiFi plugs and outlets and all are ETL certified, indicate the UL standard they comply with, rated to 15A max @ 120VAC, and cost me a mere CAD$5 each (clearance pricing at Costco). Yes, they are all manufactured in China (most electrical devices are nowadays). However, it shows that one can get a certified device inexpensively from a reputable vendor.
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Well, one example would be Lutron Caseta. It may even be made in China but it’s not Cheap and it’s not Crap. It’s UL & CSA certified, but more than that is that the brand is trusted by professionals, are commercial grade, and is an industry leader that’s been making electrical hardware since 1961, and they actually invented the dimmer switch. There’s a number of good reasons why there’s a group of us on here who do not bat an eye at paying $50 for a Lutron dimmer or plug.
You get what you pay for or you take your chances.
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I don’t get your point :-)… I bet it’s made in china :-).
I’ve never heard of this practice. FWIW, here in the EU outlets are rated at 100% load as well. I did the electrical installation for my house myself from scratch (heavy renovation) and since I wanted it to pass inspection on the first attempt, I made sure to follow code to the letter. Nowhere was any derating mentioned for outlets.
Edit: just to clarify after reading the response below, even though NEC doesn’t apply here, derating on wire gauges and certain branch circuits is absolutely applied too depending on several factors (although not a fixed 80%), but not on outlets, switches, etc.
In the US, per the National Electrical Code (NEC) which is produced by the NFPA (National Fire Protection Agency) and is adopted both nationally and at the state level in various revisions, a branch circuit is de-rated to 80% of the protective device’s current rating. In a standard house outlet branch circuit, this means the maximum load on a 15A branch circuit should be no more than 12A. This does not mean the wire or protective device cannot handle the full 15A current, it just means when planning circuits, the conductors and protective device is selected by allowing a 20% overhead. Example, my electric convection oven is rated at 240VAC, 28.5A. Therefore, using the 80% de-rating of branch circuit protective devices, I must use a 40A breaker and appropriate 8 AWG copper wire. I cannot use a 30A breaker or else I violate the electrical code and fail inspection. Even though a 30A breaker is sufficient to protect in the event of an electrical failure while allowing normal operation.
Source: I work in industrial controls designing electrical control systems and I have a background and experience in electrical power distribution. The above applies only where the NEC has been adopted (likely just the US and to a degree Canada)
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Other way around. NEC requires sizing breakers for 80% of continuous operating loads. A few breakers are rated for max usage continually but it’s very rare. Last I checked none of the Eaton breakers are rated for this.
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Technically this is only required for continuous loads. Residential lighting doesn’t require the derating as an example. Otherwise this is correct. A device labeled for continuous has already been derated though.