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

[agoldman]

In case anyone needs another reminder....

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[LiveWire]

Why not just hit "OK"? Takes less time than off and on. And you can be moving.

Your math is wrong.

Breaker must be rated at 125% of rated load.

40 amp load x 1.25 = 50 amps.

If you divide 38 by 1.25 you get 24.

My math is fine. 38 or 40 either amount is safe. You need to multiply not divide, 38 x 1.25 is 47.5 and they don't make a 47.5 amp breaker so you go to the next size up which is 50. and #6 copper is rated at 55 amps so its a safe install if installed by a licensed electrician and inspected it will be right and I will be safe. Dont use cheap outlets. get a quality NEMA 14-50 outlet. You pay all this money for your EV so dont skimp on the products you need to charge it.

 

[CherryBomb]

Use a qualified electrician that will
Pull a permit
Install 6/6/6/3 NMB (Romex) with a 50 amp breaker (GFI per code)
Install an industrial grade NEMA 14-50 outlet
Charge at 38 amps
Get it inspected
Check torque once a year
=Safe Install with no worries.

All electrical installs that are continuous loads (running for 3 hours or more) must be rated at 125% of their rated load. So if you are planning to charge at 38 amps just divide 38 X 1.25 and it comes out to be 50 so a 50 amp breaker installed with #6 wire (which is rated at 55 amps @ 60°C ) and pulling only 38 amps will never have an issue if it's installed correctly. Just my 2 cents.

If you really want a safe applications, why use the NEMA outlet in the first place? Per the Munro Live episode, it is best to direct wire the to home EV equipment. I'm going to have the electrician do this when he installs my home equipment along with using THHN wire instead of Romex (higher temp rating and higher current rating). I would think this could end up saving you money on the install as well since you don't need the outlet nor the GFI breaker (although the wire is probably more expensive).

 

[BTRYPWRDPONY]

Absolutely. If there is a light on a couple of 3-way switches, I can't rest unless they are both in the down position when the light is off.

SAME HERE!

 

[SnBGC]

I can’t say I’ve ever seen these; not that I’m a full time sparky.

Most all residential panels are press on. Most all commercial panels have bolt on breakers. Bolt down breakers are a much more positive method and superior to the press on type.

 

[superdave80]

If you really want a safe applications, why use the NEMA outlet in the first place? Per the Munro Live episode, it is best to direct wire the to home EV equipment.

How would one hardwire the portable charger that comes with the Mach E?

 

[kindofblue]

@Administrator Please make this a sticky thread. It's a topic that needs maximum exposure that persists on the forum. Thanks.

 

[Pioneer74]

How would one hardwire the portable charger that comes with the Mach E?

You could cut the plug off and hardwire it into a junction box. but I wouldn't recommend it.

 

[CherryBomb]

How would one hardwire the portable charger that comes with the Mach E?

Yeah that's the rub ... This was mentioned in the episode as well. I believe it was suggested that we don't use the mobile charger on a daily basis as these NEMA outlets aren't made for repeated insertions even if you get a good one. They will wear out over time and become loose thereby becoming more dangerous. I plan on keeping mine in the car and using it only when I need it when on the road. I figure I spent enough money on the car, not to mention my house, that I'll spend a little more and get charging equipment installed to charge as safe as possible.

 

[dtbaker61]

If you really want a safe applications, why use the NEMA outlet in the first place? Per the Munro Live episode, it is best to direct wire the to home EV equipment. I'm going to have the electrician do this when he installs my home equipment along with using THHN wire instead of Romex (higher temp rating and higher current rating). I would think this could end up saving you money on the install as well since you don't need the outlet nor the GFI breaker (although the wire is probably more expensive).

I prefer an outlet in my garage for a couple reasons:
- easy to get another charger if one dies
- easy to take with you if you sell the house
- outlet can be used for other 240v tools, like a welder
- outlet can be used in an emergency to backfeed Generator power to the whole house. (with proper procedure to isolate from Grid, and avoid exposure to live prongs with proper procedure)

 

[Triggerhappy007]

I prefer an outlet in my garage for a couple reasons:
- easy to get another charger if one dies
- easy to take with you if you sell the house
- outlet can be used for other 240v tools, like a welder
- outlet can be used in an emergency to backfeed Generator power to the whole house. (with proper procedure to isolate from Grid, and avoid exposure to live prongs with proper procedure)

I prefer hardwired and plug in, so I have both.

 

[shelnian]

Heat in electrical connections is caused by resistance between the contacts. This is what causes failures in the HVBJB as well. This heat is equal to the current squared times the resistance. This is why higher currents lead to more failures (like DC fast charging for the HVBJB). This means it's very important to reduce the contact resistance. Generally the more metal to metal contact area in a connection, the lower the resistance.

The reason why the Hubbell and Bryant outlets are superior is because the wire lug boxes use a heavy duty, large contact area, V shape that when tightened gathers the wire strands together, increasing contact area. The cheap outlets use smaller contact area, almost flat, contacts that tend to separate the wire stands so have a much reduced contact area compared to the Hubbell and Bryant outlets. The Hubbell and Bryant outlets also require a torque of 75 in. pounds instead of 25 like the cheap ones because of this larger contact surface area. They handle higher temperatures than the cheap outlets. They also have heavier one piece power and ground contacts that the EVSE plugs into. This increases plug-unplug cycle life. None of the cheap outlets can compare.

Cleanliness is important because corrosion, dirt, and carbon can greatly increase resistance. Making sure the EVSE plug contacts are clean and free from damage before plugging it into an outlet will increase outlet life and a chance of a melt down.

Outlet should be inspected and re-torqued periodically. If the outlet feels loose when plugging and unplugging or is damaged, it should be replaced immediately.

 

[blkadr08]

Very insightful video. I did not see a solid conclusion for reducing the fire hazard of charging at home? Did anyway else? I know he mentioned using the Hubble outlet and having a dedicated charger hardwired into the house but that was it.

I agree. Pretty good problem statement, no clear solution other than don’t buy a cheap dryer outlet. It did make me go out and check my install. Great post!

 

[Vulnox]

I agree. Pretty good problem statement, no clear solution other than don’t buy a cheap dryer outlet. It did make me go out and check my install. Great post!

Well I think it's because there is no such thing as a full solution. All you can do is give tips to reduce the chances. It's not like an EVSE install is the only source of electrical fire in the house. You can have an electrical fire from a standard 120 outlet with worn out pressure contacts and some dangling curtains. Or someone running an electric heater with worn out outlets and possibly undersized wiring in the walls because 30 years ago someone cut corners.

It's all about reducing risk, I can't imagine eliminating risk is even possible.

I am surprised there aren't thermal detection circuits in these outlets or on the EVSE plugs. With the C-Max Energi, they had a problem with melting/overheating plugs on the included 120 charger. Ford released a revised version in a recall after 2015 with a thermal sensor in the plug that would shut down the EVSE if it detected high temps at the plug. How that isn't standard on all EVSEs is the question I have.

 

[Polar]

Most all residential panels are press on. Most all commercial panels have bolt on breakers. Bolt down breakers are a much more positive method and superior to the press on type.

So for all of those at home with commercial panels… they’re set! ?

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