Rate my planned charging setup

[The Duude]

I should be picking up my LR M3 in the next 2 weeks. I am getting my charging setup ready and wanted to see what everyone thinks. Please point out weak points or anything I should do differently.

I do not have a garage so this setup will be outdoor year-round in Detroit, MI weather. I currently have a 240V outlet on the side of the house near the driveway that was used by the previous homeowner to plug in large equipment and I believe his RV. My plan is to swap out that outlet for a Nema 14-50 and use the mobile connector for my daily charging. The wire running from my electrical panel to the outlet is 8 Gauge Aluminum wire. My current plan is as follows.

- Swap out the current 30amp breaker for a 40amp ( will be pulling max 32 amps for mobile connector )
- Swap out the existing outlet for a Nema 14-50 in an outdoor enclosure
- Eventually, add a waterproof box next to or below the outdoor plug to store the body of the charger during the winter months.


- Should I tail off the aluminum wire with copper using a Polaris connector ( or similar ) for a better connection to the outlet?
- I am finding many different Nema 14-50 outlets online labeled as "Commercial or industrial grade" some seem too cheap to be of good quality.
- I am between the Eaton Cooper 5754N and the Hubbel HBL9450. The Hubbel says it can only be used with copper ( why i was considering the copper tail ) wiring and I cannot find that info for the Eaton so I am currently stuck on this decision right now. I do know I do not want a low-quality outlet that I will have to worry about causing issues. I do not plan to take the mobile connector with me often but probably a handful of times throughout the year when visiting family.

Thanks,

Adam

 

[Gasaraki]

Your plan sounds good. Yeah don't buy the cheap outlets, you will regret it later. You can go with either 14-50 or 6-50. Some people like 6-50 better, 14-50 is more versatile I think.

I think 8 gauge is good enough for 32A constant rate even though it's aluminum.

 

[The Duude]

So the main question would be tail off the aluminum with a short piece of copper or not? On one hand, the copper wire should mean a better connection to the outlet but on the other hand, I will be adding more failure points.

 

[RayK]

@The Duude Were it me, I'd replace all of the Al wiring from the main panel to your new 14-50 outlet with Cu.

Do you know how old your house is, or if the wiring was upgraded since being built?

 

[The Duude]

@The Duude Were it me, I'd replace all of the Al wiring from the main panel to your new 14-50 outlet with Cu.

Do you know how old your house is, or if the wiring was upgraded since being built?

This wiring was installed new in 2009. Rerunning the entire wire length is really something I would like to avoid. The run is about 80 feet in length up and through the attic. Not something I want to replace at this time unless absolutely needed. What is the concern? I am ok with downgrading my outlet to a Nema - 14-30 and leaving the 30amp breaker in place if that is a safer option. I would still get 22 mph of charge.

Thanks,

 

[ATPMSD]

Swap out the current 30amp breaker for a 40amp ( will be pulling max 32 amps for mobile connector )

Careful, if you have a 30 amp breaker the wiring may not be suitable for higher amperage. Also, you should not install a 14-50 unless the outlet was 3-wire (hot-hot-nertral-ground), if it is 2-wire then you should use a 6-50 but….

Generally the plug should match the breaker, so using a 50 amp plug with a 40 amp breaker as you suggest is likely not code.

 

[The Duude]

It is a 3 wire and I was under the impression that code allowed the use of a Nema 14-50 outlet paired with a 40 amp outlet since there is no Nema 40 amp outlets. I would be labeling the outlet as MAX 40 amps.

I had an electrician take a look at the wire and his opinion was that I would be fine going to a 40amp on the existing wiring but like to get more than just one opinion hence why I am here.

Thanks

 

[Sophias_dad]

8 AWG aluminum is fine for 40 amps(32 continuous), per

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

I'd do whatever I could to avoid the pigtails. Its just another connection and point of failure/ignition.

I assume you realize that once you've bought all the weatherproof boxes and outlets and maybe pigtails you are describing, you'll be getting reasonably close to the cost(after tax credits) of a gen3 HPWC. (note that I believe HPWCs are not allowed to direct-connect to aluminum, so you will definitely need pigtails there)

 

[Rocky_H]

Well, my wife is from Michigan, and I know some of the crappy weather there, so overall, I just would NOT be doing this outside with an outlet AT ALL. I would just mount a wall connector hard tied on the end of that line.

Now about the circuit rating, I looked it up, and yes, the 8 gauge aluminum is rated OK for a 40A circuit. But yes, a lot of outlets and I think the lugs in the wall connector aren't made to accept aluminum wire connections, so I would probably do some intermediate thing. I don't know if that would be Polaris connectors or if a small junction box/subpanel thing is more appropriate.

 

[RayK]

This wiring was installed new in 2009. Rerunning the entire wire length is really something I would like to avoid. The run is about 80 feet in length up and through the attic. Not something I want to replace at this time unless absolutely needed. What is the concern?

My concern would be that if it was installed in the 1960's, then it's time to remove it and replace it with copper. As it's only just over 10 years old, you're probably okay. Your electrician hopefully will know what's best for your situation.

 

[ATPMSD]

I assume you realize that once you've bought all the weatherproof boxes and outlets and maybe pigtails you are describing, you'll be getting reasonably close to the cost(after tax credits) of a gen3 HPWC. (note that I believe HPWCs are not allowed to direct-connect to aluminum, so you will definitely need pigtails there)

I agree this seems like your best option. Install a Wall Connector, which is already rated for outdoor use, upgrade the breaker to 40 amps since your electrician says you are good there, and set the Wall Connecotr to 40 amps. At a future date you can upgrade the wiring and circuits breaker to 60 amps and change the setting on the Wall Connector.

Incidentially, as I understand it, code was changed to where any 240v circuit that ends at a plugs needs to use a GFI breaker, which is not cheap, thus further closing the cost gap. Final point, the Feds are giving a 30% tax credit (or $1,000, whichever is less) for installation of charging stations (materials and labor). This is good until the end of this year, so now is a good time to bite the bullet and do it right. You also may have State tax credits as well as utility credits!

 

[The Duude]

I agree this seems like your best option. Install a Wall Connector, which is already rated for outdoor use, upgrade the breaker to 40 amps since your electrician says you are good there, and set the Wall Connecotr to 40 amps. At a future date you can upgrade the wiring and circuits breaker to 60 amps and change the setting on the Wall Connector.

Incidentially, as I understand it, code was changed to where any 240v circuit that ends at a plugs needs to use a GFI breaker, which is not cheap, thus further closing the cost gap. Final point, the Feds are giving a 30% tax credit (or $1,000, whichever is less) for installation of charging stations (materials and labor). This is good until the end of this year, so now is a good time to bite the bullet and do it right. You also may have State tax credits as well as utility credits!

Fed tax credit for charging install of 1000?$ I am looking into this right away. I see a new wall charger in my future.

thank you,

 

[ATPMSD]

About Form 8911, Alternative Fuel Vehicle Refueling Property Credit | Internal Revenue Service

Form 8911 is used to figure a credit for an alternative fuel vehicle refueling property placed in service during the tax year. The credit attributable to depreciable property (refueling property used for business or investment purposes) is treated as a general business credit. Use this form to...

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[Sophias_dad]

Fed tax credit for charging install of 1000?

That is, Fed tax credit of 30% of whatever your charging install cost was, up to a maximum of $1000 credit. I'm not sure whether a 14-50 and UMC would count at all.

 

[KenC]

if it was done in 2009, why not just get an adapter for the pigtail of your UMC to match? There's nothing wrong with 24amps, if it's a 30amp outlet.

 

[JoshFalken]

8 AWG aluminum is fine for 40 amps(32 continuous), per

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

I'd do whatever I could to avoid the pigtails. Its just another connection and point of failure/ignition.

I assume you realize that once you've bought all the weatherproof boxes and outlets and maybe pigtails you are describing, you'll be getting reasonably close to the cost(after tax credits) of a gen3 HPWC. (note that I believe HPWCs are not allowed to direct-connect to aluminum, so you will definitely need pigtails there)

I’d consider this if I were you. I did something similar to what you described with a CMC and NEMA 14-50. I’m happy with it since my daughter may need to use the 14-50 for their RV on occasion. Otherwise I would have spent less on a HPWC. Setup is below.

 

[Watts_Up]

I currently have a 240V outlet on the side of the house near the driveway that was used by the previous homeowner to plug in large equipment and I believe his RV. My plan is to swap out that outlet for a Nema 14-50 and use the mobile connector for my daily charging. The wire running from my electrical panel to the outlet is 8 Gauge Aluminum wire. My current plan is as follows.

- Swap out the current 30amp breaker for a 40amp ( will be pulling max 32 amps for mobile connector )
- Swap out the existing outlet for a Nema 14-50 in an outdoor enclosure

Are you sure this is not a NEMA TT-30R (Travel Trailer) 120 V 30 A?

 

[Jack6591]

When I became an electrician my hair was black. It’s been decades. I only mentioned that because I’m set in my ways, and do things in particular way.

In an industrial environment I have used aluminum wiring for feeders (panel feeds). I’m not a fan of aluminum wiring for branch circuits. Read that as personal preference. Copper is simply more durable, especially for outlets that will be repeatedly plugged in and out.

The question for me would be the distance from the panel to the outlet? What would it cost to upgrade the wiring to copper. I just prefer copper over aluminum.

 

[roblab]

Fed tax credit for charging install of 1000?$ I am looking into this right away. I see a new wall charger in my future.

thank you,

Well, I've been using a 14-50 outlet since I got my first EV back in 2002. Still using the same one. If I'd only known, I could have spent a thousand bucks on a charger and had the same utility I have now. How does a "wall charger" do the job any better? Oh, right, it charges your car clear up while you sleep. Sort of like what I have now.

 

[Watts_Up]

The question for me would be the distance from the panel to the outlet? What would it cost to upgrade the wiring to copper. I just prefer copper over aluminum.

I have Aluminum Romex in my home, I added a 150 ft. extension for my EV plug using copper
and used Polaris connectors inside a connection box to connect the two types of wires.

To replace aluminum with copper I would have to break my walls in many places, something I didn't want to do.

I build a 30 Amp line for charging at 24 Amp, I don't think it was worthwhile to build a 50 Amp line for only 32 Amp charging.
I get about 200 miles in 8 hours charging, which is way more than my daily commute.