EV Charger Risks: Home Charging Installation Risks and Advice [by Munro Live]

[mkhuffman]

So glad damage was minimal.

can’t a direct wiring have problems with a wire that comes lose no differently from an outlet?

Yes but it would be inside the EVSE or inside a metal junction box, instead of an outlet inside a wall.

Edit: when you plug/unplug, the blades move a little, increasing the chance a wire will losen.

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[Maquis]

This is the best information I have read so far, thanks for sharing!

Munro and company had some just plain wrong information in their video, as do many people posting here. Lots of guessing with no research into the actual standards to back it up.

(TLDR; Lots of misinformation, but be careful with high voltage, high amperage, and regularly check for heat damage.)

There is no 'duty rating' for home electrical outlets or a disconnector, just the rated maximum allowed current draw as labeled, and the maximum current draw for 'continuous load', which is 80% of rated. 'Continuous Load' is defined as 3 hours or longer. So a 14-50 should be able to draw 50 amps for up to 3 hours, or 40 amps when used for more than 3 hours at a time. Of course, only some electrical components are pulled for testing, so it is entirely possible to get faulty items, regardless of brand. And running anything at its maximum rating for long periods of time is going to have some affect on longevity, nothing lasts forever. (The monster 383 motor I built for my old Jeep can attest to how maximum RPM affects the ability of the motor to keep all of its moving parts inside... LOL But it did not burn my house down when it failed.)

From everything I have found, the vast majority of meltdowns for receptacles used for EVSEs are caused by bad wire connections, meaning improper torque on conductor screws. Monro was correct that too much or too little is very, very bad. I don't remember the torque spec for my receptacle, but it was considerable higher than I thought it would be, and would not be easily obtained with just a screwdriver. I used my 1/4" torque wrench with a driver bit, and it took some effort. Bad connections happen for driers and welders and every other thigh amperage plug in equipment too, but EVSEs do draw high current for longer periods than most of those, so the problem tends to show up more easily. And it is never a bad idea to go back after a new installation has been used at high amperage for a bit and recheck the torque at least once. The heat cycle can affect it apparently.

There is no 'industrial" vs "home" or other standard for home electrical connectors. Are some receptacles better quality than others? Absolutely. But they all should be able to handle their maximum rating for under 3 hours at at time, or 80% of their rating indefinitely. A bakelite receptacle will definitely stay together longer than a nylon one under high heat, but if it is getting hot enough to melt nylon, it is not the insulator material that is the problem, it is high resistance and needs to be fixed.

Almost all meltdowns happen at connection points, (all in the video did) and it is always due to high electrical resistance at that point, which means not enough contact, turning the metal into a heater. Besides torque on screws, low contact can be caused by loose fitting contact points between the plug and the receptacle. If you do have to plug and unplug an electrical connection often, this is where the quality of receptacle DOES matter, as receptacles DO have a limited plug / unplug cycles and the quality matters. My EVSE never gets unplugged, and my $12 receptacle has been just fine for almost 2 years. I do check it once in awhile while the car is charging, just to be sure it is not more than warm to the touch. I charge at 30a to be kind to the battery, so my plug has always been cool. To be honest, I wanted a buy little better quality, but there was barely anything on the shelves when I put my outlet in so I had to take what I could get.

I live in AZ, and I can assure you that in the summer, when we get days when the overnight low is near 100 degrees, the breakers and disconnects on my 2 AC units often run at nearly maximum continuous load for well over 3 hours at a time. They hold up without problems, and I believe the reason is proper installation, from breakers, to wire size, to proper torque.

You can never be too careful with high voltage, high amperage equipment of any kind, so my advice is to be proactive and check your EVSE connections regularly for any signs of heat damage. Now that I wrote that, I am going to make a point to check mine this weekend...

While I agree the nomenclature of ”commercial vs industrial” doesn’t mean much, there is a difference between receptacles. The cheap ones have a screw that twists directly on the stranded wire, while the better ones have a saddle that compresses the wire without twisting it and pushing it out of the clamping area. The cheaper one will be OK as long as you’re diligent about installing properly and keeping an eye on them, which it seems you are.

 

[kennethjk]

Yes but it would be inside the EVSE or inside a metal junction box, instead of an outlet inside a wall.

Edit: when you plug/unplug, the blades move a little, increasing the chance a wire will losen.

I would think most of the EVSE’s have plenty of plastic, the Juicebox does but I haven’t opened it up .

my Hubbell is in a metal box outside the wall not inside . Other than a particular issue I would not be plugging and unplugging the the blades. I don’t know what type of screws hold the wires in the EVSE’s. As someone mentioned above the Hubbell has clamps which seem to be a better connection than other outlets but I am not an electrician.

I asked the electrician who installed my unit in Fl and he had no issue with the junction box instead of a direct connection but as many had said they arent experts in EVSE’s.

He brought an outlet to use but it wasn’t the Hubbell. I gave him the Hubbel I had bought instead. I guess that says it all.

what is interesting is that the Autel unit I have in Florida runs much cooler (plug) than the Juicebox I have in NY. The Autel also weights a lot more. I have had the Juicebox connection checked twice since I started using it in March and connections are fine. Juicebox does not run hot , just warm and the Autel isn’t even warm. Just an FYI

 

[mkhuffman]

I would think most of the EVSE’s have plenty of plastic, the Juicebox does but I haven’t opened it up .

my Hubbell is in a metal box outside the wall not inside . Other than a particular issue I would not be plugging and unplugging the the blades. I don’t know what type of screws hold the wires in the EVSE’s. As someone mentioned above the Hubbell has clamps which seem to be a better connection than other outlets but I am not an electrician.

I asked the electrician who installed my unit in Fl and he had no issue with the junction box instead of a direct connection but as many had said they arent experts in EVSE’s.

He brought an outlet to use but it wasn’t the Hubbell. I gave him the Hubbel I had bought instead. I guess that says it all.

what is interesting is that the Autel unit I have in Florida runs much cooler (plug) than the Juicebox I have in NY. The Autel also weights a lot more. I have had the Juicebox connection checked twice since I started using it in March and connections are fine. Juicebox does not run hot , just warm and the Autel isn’t even warm. Just an FYI

Another forum member recommended periodically re-tightening the screws. Personally I think it is a really good idea to re-tighten the screws after the device (outlet, EVSE, junction box) has been through several hot/cold cycles, as temperature changes could also loosen things up.

One re-tighten a few weeks after installation, and then another one year after seems like a good practice that I should probably do, but have not. It has been a year since I put my EVSE in, so I probably should open it up and make sure the screws are still tight.

 

[dmac1418]

Question for people who had had 14-50 outlets installed.

I had an electrician install the outlet & breaker today, but the installed breaker is 40A, even though he confirmed the wiring supports 50A. I didn't catch it before he left.

He's saying that the city will require a 40A breaker for my charger (Wallbox Pulsar Plus 40A).

Should I make them return to put in the 50A breaker since that's what they quoted?

 

[mkhuffman]

Question for people who had had 14-50 outlets installed.

I had an electrician install the outlet & breaker today, but the installed breaker is 40A, even though he confirmed the wiring supports 50A. I didn't catch it before he left.

He's saying that the city will require a 40A breaker for my charger (Wallbox Pulsar Plus 40A).

Should I make them return to put in the 50A breaker since that's what they quoted?

My opinion is yes, you definitely should have a 50 Amp breaker on a 50 Amp circuit. His comment makes no sense unless he didn't use AWG 6 wire. Your Wallbox 40 Amp charger is going to blow that 40 Amp breaker, I am almost sure of it. It will run for 20 minutes? 30 minutes? Or maybe less. You cannot run 40 Amps continuous through a 40 Amp breaker.

 

[dmac1418]

My opinion is yes, you definitely should have a 50 Amp breaker on a 50 Amp circuit. His comment makes no sense unless he didn't use AWG 6 wire. Your Wallbox 40 Amp charger is going to blow that 40 Amp breaker, I am almost sure of it. It will run for 20 minutes? 30 minutes? Or maybe less. You cannot run 40 Amps continuous through a 40 Amp breaker.

Thanks, that's what I thought.

I have him in writing confirming that the wiring is good for 50A. I also confirmed the WallBox manual says to use a 50A circuit.

 

[dmac1418]

Thanks, that's what I thought.

I have him in writing confirming that the wiring is good for 50A. I also confirmed the WallBox manual says to use a 50A circuit.

My electrician explained that a while back he installed a Wallbox for someone else in my city and the inspector made him change from 50A to 40A.

In the end, he did install the 50A breaker, and today's inspector signed off with no issue.

 

[AZBill]

I would think most of the EVSE’s have plenty of plastic, the Juicebox does but I haven’t opened it up .

my Hubbell is in a metal box outside the wall not inside . Other than a particular issue I would not be plugging and unplugging the the blades. I don’t know what type of screws hold the wires in the EVSE’s. As someone mentioned above the Hubbell has clamps which seem to be a better connection than other outlets but I am not an electrician.

I asked the electrician who installed my unit in Fl and he had no issue with the junction box instead of a direct connection but as many had said they arent experts in EVSE’s.

He brought an outlet to use but it wasn’t the Hubbell. I gave him the Hubbel I had bought instead. I guess that says it all.

what is interesting is that the Autel unit I have in Florida runs much cooler (plug) than the Juicebox I have in NY. The Autel also weights a lot more. I have had the Juicebox connection checked twice since I started using it in March and connections are fine. Juicebox does not run hot , just warm and the Autel isn’t even warm. Just an FYI

My ChargePoint uses a lever and saddle to hold the wires, no screws. FYI, I confirmed the wires to my burned outlet were 4awg, so those were more than sufficient to handle the 40A. I am running 6 awg (90C) with a short run now, because the CP cannot accept 4 awg. The wires from the panel to the new charger location will be less than 3 feet.

 

[Guppydriver]

I just had an electrician come over today and give me a bid for Nema 14-50 garage install. Unfortunately, I found this thread after he left. I will text him to clarify that proper gauge and receptacle are included. I'm worried because his quote seemed relatively affordable at 1k. I think I may just buy the Bryant and give it to him when he returns next week. Anyone know what box and plate should be purchased with it?

Also...make fun, it's fine.. I have an idiot question(s).

1. When you say proper torque is vital, which screws on the installation are you talking about? Just in case I want to check when he leaves.

2. My run appears pretty long to get the box centered in my garage. I'd guess close to 50 feet (max) unless he can go through the ceiling. It sounds like some have suggested 4 gauge with a run this long. Assuming his quote is 6, how much more should I expect him to charge if I want 4 gauge?

TIA

 

[mkhuffman]

I just had an electrician come over today and give me a bid for Nema 14-50 garage install. Unfortunately, I found this thread after he left. I will text him to clarify that proper gauge and receptacle are included. I'm worried because his quote seemed relatively affordable at 1k. I think I may just buy the Bryant and give it to him when he returns next week. Anyone know what box and plate should be purchased with it?

Also...make fun, it's fine.. I have an idiot question(s).

1. When you say proper torque is vital, which screws on the installation are you talking about? Just in case I want to check when he leaves.

2. My run appears pretty long to get the box centered in my garage. I'd guess close to 50 feet (max) unless he can go through the ceiling. It sounds like some have suggested 4 gauge with a run this long. Assuming his quote is 6, how much more should I expect him to charge if I want 4 gauge?

TIA

IMO 50 gauge is fine for a 50 foot run. The cheaper outlets (assuming he used one) are fine but they just can't handle as many plug/unplug cycles, in theory. They are not as robust for sure. I would leave it for now and then maybe upgrade later if you find yourself plugging/unplugging frequently.

The screws you want to check are the screws that attach the wires inside the outlet. If you got a good electrician, you can double check his work but I would also not worry about that for now. I would check the screws in 6 months to a year and retighten them. (I should do that with mine since it has been over a year. I don't use the outlet though.)

$1k seems like the right price depending on the complexity of the run.

This thread obviously got you worried but nothing you described would worry me. Have a great weekend and enjoy your car!

 

[21st Century Pony]

IMO 50 gauge is fine for a 50 foot run. The cheaper outlets (assuming he used one) are fine but they just can't handle as many plug/unplug cycles, in theory. They are not as robust for sure. I would leave it for now and then maybe upgrade later if you find yourself plugging/unplugging frequently.

The screws you want to check are the screws that attach the wires inside the outlet. If you got a good electrician, you can double check his work but I would also not worry about that for now. I would check the screws in 6 months to a year and retighten them. (I should do that with mine since it has been over a year. I don't use the outlet though.)

$1k seems like the right price depending on the complexity of the run.

This thread obviously got you worried but nothing you described would worry me. Have a great weekend and enjoy your car!

The main expense for a 50-foot run would likely be the copper wire in a heavy gage.

Quality matters mainly in the receptacle. The enclosure boxes, plates, conduit etc. are almost interchangeable commodities, imho.

 

[Guppydriver]

IMO 50 gauge is fine for a 50 foot run. The cheaper outlets (assuming he used one) are fine but they just can't handle as many plug/unplug cycles, in theory. They are not as robust for sure. I would leave it for now and then maybe upgrade later if you find yourself plugging/unplugging frequently.

The screws you want to check are the screws that attach the wires inside the outlet. If you got a good electrician, you can double check his work but I would also not worry about that for now. I would check the screws in 6 months to a year and retighten them. (I should do that with mine since it has been over a year. I don't use the outlet though.)

$1k seems like the right price depending on the complexity of the run.

This thread obviously got you worried but nothing you described would worry me. Have a great weekend and enjoy your car!

Thanks @mkhuffman

The good part is he HASN'T installed it yet. He was just in the area and stopped but to give me a quote. I just wasn't armed with this thread knowledge at the time, but now I can text him. I'm going to buy an industrial receptable for sure, a n.o brainer since I am saving money by buying a "dumb" Grizzl-E EVSE. I just have to make sure I buy the right box and plate to fit the Bryant.

I won't pay the extra money for 4awg, but will obviously insist on 6awg

 

[Guppydriver]

Also...

I'm about to order the Bryant recep on Grainger's site. I need a box and cover, and I've read that the standard Lowe's and HD ones don't fit. Any amazon recommendations on what will work ? I assume the box and cover that works with a Hubbell will be compatible with the Bryant. I only ask but the Hubbell receptacle has a "frequently bought together" recommendation that I can use to select the box and cover..lol.

 

[mkhuffman]

Also...

I'm about to order the Bryant recep on Grainger's site. I need a box and cover, and I've read that the standard Lowe's and HD ones don't fit. Any amazon recommendations on what will work ? I assume the box and cover that works with a Hubbell will be compatible with the Bryant. I only ask but the Hubbell receptacle has a "frequently bought together" recommendation that I can use to select the box and cover..lol.

I used the Lowe's outlet when I put mine in so maybe someone else has a suggestion.

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