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Definitely want to make sure you aren't charging in open sunlight, that doesn't help. Also want to make sure extension cords are not being used, they can definitely cause the plug melt. There are other factors as well, it's not all just the charger's fault. Just an fyi for those looking to discuss it here.
 

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Most of the problems as shown in the picture are the wall outlet: worn or loose contacts or wiring cause it to overheat and melt everything around it. A good way to start house fires, too. And all that for saving a few $$ buying the cheap chinese outlet instead of a quality one.
:shrug:
 

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Most of the problems as shown in the picture are the wall outlet: worn or loose contacts or wiring cause it to overheat and melt everything around it. A good way to start house fires, too. And all that for saving a few $$ buying the cheap chinese outlet instead of a quality one.
:shrug:
My personal take on that thread was that smart should not have shipped a charger that had the potential of causing a fire although there might have been warnings to not use the charger on the higher power settings. What was brought up was that the charger has two charge rate settings and I don't think it was mentioned as to what rate the charger was set to when the outlet/plug melted. And that would be of concern to me since the odds of you having a higher quality outlet installed in your garage where you were plugging this charger in are unlikely. I think someone also mentioned that they melted not only a standard outlet but a GFI outlet as well so bottom line is I think the charger has to be also partly at fault as it can be potentially set to exceed the ratings of your typical house outlet.

Outlets have to be CSA approved up here btw also the outlets are installed by the builder and all are rated at 15 amps. Builders will install the cheapest parts they can source as well as put as many outlets on as few circuits as possible (bulk packs at Home Depot) but all are CSA rated at 15 amps. I know of no builder that would install a 20 amp outlet unless it was specifically called for when the home was built. As a home owner you can certainly replace the outlet with a higher spec'd version however I would then upgrade the breaker but the next weakest link would be your house wiring and how many other outlets are on that circuit.

I know this from when we built our house I specified 200 amp service since the builder was only doing 100 amp, you would think today that homes would be built with upgraded service since we have so many more electrical devices but I guess not. Also put many of our rooms on separate circuits, builder had wanted to run the entire upstairs on two but I put a number of very specific requirements in our contract. We wired the home for 100T ethernet and cable tv for example since those were not included in the build but extras. When we studded and reinsulated the basement I ran a 240v line from the box to the garage. I had never thought about an EV charging station at the time, that was set up to hook up our generator. Guess that part is more for someone about to do a new build but look over the plans and make sure you are putting in what you want in the walls before it's all covered up.

Anyhow I'm not so sure I would be quick to blame just the outlet, there were probably several factors involved.
 

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My personal take on that thread was that smart should not have shipped a charger that had the potential of causing a fire although there might have been warnings to not use the charger on the higher power settings.
"The potential of causing a fire?" Doesn't some "responsibility" lie with the owner to not just plug and play without knowing the impact of the draw vs. circuit capacity?

SCoA has some of the best on-line CSI investigators on the Interweb and now we take it "Beyond Borders!"

While not all the facts are in, the wall outlet and circuit capacity are the likely suspects - NOT the EVSE?

That being said, it is understandable that M-B/smart is expecting a "used" but not abused EVSE be returned with their leased ED.
 

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This isn't rocket science. The typical garage circuit is rated for 12A continuous (15A circuit). The EVSE will run at 12A. I expect most people to use 12A because it charges faster. (duh).

Connection points are subject to increased resistance, and thus heat, due to poor mechanical fit, corrosion, dirt, wear and tear etc. Hence the problem at the plug / receptacle.

The EVSE design isn't faulty. Neither is the receptacle. But operating at the edge of what is possible is likely to cause problems sooner rather than later.

I'd recommend anyone who can, to install a dedicated EVSE in their garage. Even if it is a plug in unit, it will be safer than a less robust connection like your typical wall plug.
 

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"The potential of causing a fire?" Doesn't some "responsibility" lie with the owner to not just plug and play without knowing the impact of the draw vs. circuit capacity?

SCoA has some of the best on-line CSI investigators on the Interweb and now we take it "Beyond Borders!"

While not all the facts are in, the wall outlet and circuit capacity are the likely suspects - NOT the EVSE?

That being said, it is understandable that M-B/smart is expecting a "used" but not abused EVSE be returned with their leased ED.
I went and looked through the owners manual for an EV smart and did not find any reference to recommended settings. I did however see warnings about not using extension cords and that the outlet used was approved by a qualified electrician. So looking at the failed outlet and it being on what appears to be a finished wall I would assume that this outlet was installed by or approved by a qualified electrician. Therefore what went wrong? Well obviously the device drew more current then the outlet could safely handle however if you were to look at any outlet in your home you will likely find that it was rated at 15 amps which is industry standard. In our media room I had two outlets upgraded to 20amp so that I could safely operate very large UPS units, but these plugs have slightly different plug styles plus each of outlets is a homerun to the panel with no other outlets after each.



As one of the clubsmartcar users mentioned they did a homerun to their outlet which makes sense to me though given what occurred I can't help but be concerned that even with that precaution this event could be prevented.

Incorrect in assuming that "While not all the facts are in, the wall outlet and circuit capacity are the likely suspects - NOT the EVSE?" since the EV charger had to be drawing current through it's regulated charging circuit and that exceeded the limits of the wall outlet I would have to wonder if it was the culprit. I get that cheap outlets can be the source however given that logic we could all be sitting on ticking time bombs since how many of you have upgraded your wiring, outlets and breakers?

I've always considered the term interweb to be derogatory,

Definition: The term Interweb, a combination of the words Internet and Web, is most often used in the context of joking or sarcasm, especially when talking about or to a person who is not familiar with the online terminology. It can also be used as a euphemism for the vast information that is available on the Web, or in a parody of someone's knowledge of or experience with Web culture.

Alternate Spellings: Interwebs, Intarwebs

Examples: "Look at me! I'm on the Interwebs, Mom!" "Do you think that the Interwebs could help me find that recipe?"
 

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I've always considered the term interweb to be derogatory,

Definition: The term Interweb, a combination of the words Internet and Web, is most often used in the context of joking or sarcasm, especially when talking about or to a person who is not familiar with the online terminology.
Probably need to let go of that feeling of my (now labelled) "derogatory" response being aimed at you - it was simply in response to an open Forum thread?

The entire sentence - "SCoA has some of the best on-line CSI investigators on the Interweb and now we take it "Beyond Borders!" is SARCASM aimed at no one, myself included as a member of this Forum!

And the manual that comes with the "fully J1772 compliant so it works on cars such as the BMW Active E, Chevy Spark and Volt, Toyota Prius, Nissan Leaf, Tesla Roadster and Model S" EVSE at delivery . . .

http://evwest.com/support/Lear-EVSE.pdf
 

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Just a clarification for anyone NOT familiar with the electrical code. You CANNOT simply replace a 15A receptacle with a 20A receptacle. The wire used has to be a 12 gauge. 15A wiring is 14 gauge.

I think someone commented on using a commercial grade 15A receptacle. There are what are termed "hospital grade" units.
These are much more robust.
 

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Just a clarification for anyone NOT familiar with the electrical code. You CANNOT simply replace a 15A receptacle with a 20A receptacle. The wire used has to be a 12 gauge. 15A wiring is 14 gauge.

I think someone commented on using a commercial grade 15A receptacle. There are what are termed "hospital grade" units.
These are much more robust.
Good point, in our build contract I had specified 12 gauge throughout and when we did the run to the garage I installed 10 3.
 

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Just a clarification for anyone NOT familiar with the electrical code. You CANNOT simply replace a 15A receptacle with a 20A receptacle. The wire used has to be a 12 gauge. 15A wiring is 14 gauge.

I think someone commented on using a commercial grade 15A receptacle. There are what are termed "hospital grade" units.
These are much more robust.
That might be the case in Canada, but not here in the US. You can replace a 15A rated duplex with a 20A rated duplex in your home. 20A is simply the RATING of that receptacle. Where you need to be careful is the rating of the breaker that is feeding that device. If you have 14 AWG wire, then the breaker must be 15A or less. 12 AWG would be 20A, and 10 AWG would be 30A. I have worked in the electrical industry all of my life. I have seen a lot of melted/exploded/destroyed equipment. The actual contact points in cheap duplex receptacles is laughingly small. While this is fine 99.9% of the time, running low drain loads or even high drain loads for short durations(think toaster), if you have a high drain long duration load, that duplex is going to get warm. As the temperature increases, resistance increases. Bad cycle. If you are going to charge your EV on a 120V circuit, please spend 10 bucks and buy an industrial or hospital grade 20A rated duplex OR GFCI. They have much more robust contact surfaces and higher clamping tension. They will run much cooler. Even if you don't run 12 or 10 gauge wire, you should be OK with the 14 as long as there is no other load on that circuit.
As the extension cord issue, if you have a 10 gauge extension cord, you could use it with no issues. The EVSE doesn't know the difference between the copper conductor in your walls Vs the copper conductors in that extension cord. Where you run into trouble is that the vast majority of extension cords are either 18-16, or 14 gauge. Those will overheat and melt.

One more thing. NEVER "back wire" a receptacle. ALWAYS use the screws on the sides. The contact point when you back wire is TINY.
 

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That might be the case in Canada, but not here in the US. You can replace a 15A rated duplex with a 20A rated duplex in your home. 20A is simply the RATING of that receptacle. Where you need to be careful is the rating of the breaker that is feeding that device. If you have 14 AWG wire, then the breaker must be 15A or less. 12 AWG would be 20A, and 10 AWG would be 30A.
I certainly won't dispute legalities but it just seems, let us say "unwise" to install a receptacle that is visually different and rated for 20A on a 15A circuit.

Someone who is not familiar with the details of the electrical code would not unreasonably expect a 20A receptacle to provide for a load that could pull 16A continuous. Resulting in a blown breaker, or worse, overheating somewhere inside your wall.

If you need to put a more robust 15A receptacle on a 15A circuit use one of those hospital grade units.
 

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That might be the case in Canada, but not here in the US. You can replace a 15A rated duplex with a 20A rated duplex in your home. 20A is simply the RATING of that receptacle. Where you need to be careful is the rating of the breaker that is feeding that device. If you have 14 AWG wire, then the breaker must be 15A or less. 12 AWG would be 20A, and 10 AWG would be 30A. I have worked in the electrical industry all of my life. I have seen a lot of melted/exploded/destroyed equipment. The actual contact points in cheap duplex receptacles is laughingly small. While this is fine 99.9% of the time, running low drain loads or even high drain loads for short durations(think toaster), if you have a high drain long duration load, that duplex is going to get warm. As the temperature increases, resistance increases. Bad cycle. If you are going to charge your EV on a 120V circuit, please spend 10 bucks and buy an industrial or hospital grade 20A rated duplex OR GFCI. They have much more robust contact surfaces and higher clamping tension. They will run much cooler. Even if you don't run 12 or 10 gauge wire, you should be OK with the 14 as long as there is no other load on that circuit.
As the extension cord issue, if you have a 10 gauge extension cord, you could use it with no issues. The EVSE doesn't know the difference between the copper conductor in your walls Vs the copper conductors in that extension cord. Where you run into trouble is that the vast majority of extension cords are either 18-16, or 14 gauge. Those will overheat and melt.

One more thing. NEVER "back wire" a receptacle. ALWAYS use the screws on the sides. The contact point when you back wire is TINY.
You both just pretty much said the same thing. :nerd:
 

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I certainly won't dispute legalities but it just seems, let us say "unwise" to install a receptacle that is visually different and rated for 20A on a 15A circuit.

Someone who is not familiar with the details of the electrical code would not unreasonably expect a 20A receptacle to provide for a load that could pull 16A continuous. Resulting in a blown breaker, or worse, overheating somewhere inside your wall.

If you need to put a more robust 15A receptacle on a 15A circuit use one of those hospital grade units.
I understand your point Blaine. I would make a habit out of doing this, but for someone to do this in their own home for their own use would be fine. I would not recommend doing it for a new installation in someone else's home. If someone were to pull a 16A load through a 15A 14AWG circuit, That breaker will trip(not blow), requiring a reset. The breaker will trip long before the branch circuit wiring will heat up.
One thing that most people don't know is that modern circuit breakers (and fuses) are designed to only allow 80% current let through on a continuous basis. Continuous is defined as longer than 3 hours. In other words, if you have a load in excess of 12 Amps running longer than 3 hours, that breaker is designed to trip. If your EVSE is pulling 12 amps, you are on the very edge of that 15A circuits operating parameters, and the breaker could very likely trip after being on for a long period of time. That is one reason it is so important to not put any other loads on that circuit. Being that breakers do have a manufacturing tolerance, it is quite possible that your 12A EVSE will never trip that breaker, especially if the ambient temperature in that breaker panel isn't high.

The NEC (National electric code) is pretty conservative, and in most cases 14AWG copper wire can easily handle in excess of 15A. In the interest of not burning down your house, conservative is better.
 

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"One more thing. NEVER "back wire" a receptacle. ALWAYS use the screws on the sides. The contact point when you back wire is TINY."
Why wold be the push-in wire connections on a receptacle be present and allowed by the (generally very conservative) electric code if they are not adequate for the receptacle's 15A/12A continuous rating?
 

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Why would be the push-in wire connections on a receptacle be present and allowed by the (generally very conservative) electric code if they are not adequate for the receptacle's 15A/12A continuous rating?
Building codes, and the electrical code, is typically the minimum considered safe under 'normal' conditions. Plus there is an economic consideration...

The push-in connections are done for speed wiring and are there to support electricians who are building to price in volume. To the minimum standard acceptable.

In most "normal" cases you don't pull 12A continuous or other high loads through something that is push wired. Its more likely your lamp, or a laptop or phone charger. So its 'ok'. And the breaker will probably protect you anyway.

I can say from personal experience though that upon replacing a bunch of push wired receptacles in our home the frequency of weirdness, blown breakers etc. went to zero.
Were we ever not 'safe'? Who knows. Do I feel safer now? Yup. But I'm in the over-engineered nerdy fringe.
 
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