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Which electrical charger installation proposals should I pick?

Hi all, I live in Chicago and am looking for electricians to install a 240V outlet in my detached garage for a Model Y expected at EOY. I got several proposals and eliminated them to two of the ideal ones. I know nothing about electricity so I am looking for some advice on which one to pick:

Background: Total 100 AMP with limited to no extra spaces in the panel.

First Proposal: $1,500 for a panel swap with a new Siemens 100 AMP, 32-space panel, and $2,500 for the power brought to the garage via underground pipe. Total: $4,000

Second Proposal: Install a new sub-panel and power brought to the garage through the roof. Total: $3,352

Based on my research, I should choose the second proposal because it is safer and cheaper to install a sub-panel; however, I do have a problem with my current panel where occasionally my lights dim or flash during the winter when my furnace is on, so I am debating on the first proposal as well. Can someone please give me some suggestions?
 
6-6-6-6 Ser is 2.85 a foot…
I'm seeing this for AL wire:
6-6-6-6 Chola Quadruplex Overhead Aluminum Conductor
Availability: In stockMin Length: 1 FT Max Length: 1000000 FT
Regular price
$2.50
Sale price
$1.18 /FT Sale 52% off
 
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qdeathstar

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So what typically is the break even point (length of wire run required) when it makes sense to use Aluminum wire and a sub panel or a service disconnect box?
I think it is more of a matter of amps that distance. Over 100 amps I would use aluminum conductors maybe. But for instance when I upgrade panels to 200 amps and everything is close I use 2/0 copper because it is a lot easier to work with that 4/0 aluminum.

Aluminum wiring and it’s insulation is physically bigger. I’m not a nickel and dime electrician though. I use copper charge for copper and I’m not that worried about the cost because my customers are willing to pay me a premium. Aluminum sucks to work with, imo
 
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qdeathstar

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I'm seeing this for AL wire:
6-6-6-6 Chola Quadruplex Overhead Aluminum Conductor
Availability: In stockMin Length: 1 FT Max Length: 1000000 FT
Regular price
$2.50
Sale price
$1.18 /FT Sale 52% off

That is not acceptable for running in walls.
 
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jcanoe

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Oct 2, 2020
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It might make sense to install a 100 amp rated sub panel using aluminum wire, now, even though there is limited capacity, i.e. 30 amp available on the existing 100 amp service panel. Later, if you decide to upgrade the service to 200 amp and install a new service panel the sub panel will be able to support either additional circuit(s) and/or a larger rated charging circuit.
 
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Sophias_dad

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Either you're overloading your current 100 amp service with too many simultaneous runnig appliances or that one of your appliances is pulling too much power.
This is an incorrect statement.

It could be an overload condition as you state, or it could be a bad connection either in the panel or the feeder for the panel, or just a dubious main circuit breaker. Connections in the panel include the screwed connections to circuits, the clip-on connections that most breakers use to connect to the bus bars, or the connections from the feed line to the main breaker.
 
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qdeathstar

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This is an incorrect statement.

It could be an overload condition as you state, or it could be a bad connection either in the panel or the feeder for the panel, or just a dubious main circuit breaker. Connections in the panel include the screwed connections to circuits, the clip-on connections that most breakers use to connect to the bus bars, or the connections from the feed line to the main breaker.

Overloads don’t usually cause the lights to dim. They usually cause the breaker to trip or the fuse to blow. Though running an circuit at close to its maximum ampacity could cause a loose connection…
 
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That is not acceptable for running in walls.
Sure, unshielded wire is not used in walls.
But in conduit its fine, right?
THHN in conduit was used in the installation of my EVSE in the garage. At the time, I did not consider AL wire. But it sounds like with a junction box, AL wire would have been a copper THHN replacement.
Overloads don’t usually cause the lights to dim. They usually cause the breaker to trip or the fuse to blow.
Since you are the electrician, I'll defer to you.
In my mind, dimming of lights means the voltage has drooped. The voltage drooping is due to power lost in the wiring. This could be due to undersized wires with a load which might match the circuit breaker. The current just needs to be high enough to cause excess power lost in the wiring. This doesn't necessarily mean the circuit breaker will trip.
 
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Sure, unshielded wire is not used in walls.
But in conduit its fine, right?
THHN in conduit was used in the installation of my EVSE in the garage. At the time, I did not consider AL wire. But it sounds like with a junction box, AL wire would have been a copper THHN replacement.

Since you are the electrician, I'll defer to you.
In my mind, dimming of lights means the voltage has drooped. The voltage drooping is due to power lost in the wiring. This could be due to undersized wires with a load which might match the circuit breaker. The current just needs to be high enough to cause excess power lost in the wiring. This doesn't necessarily mean the circuit breaker will trip.
Um. I troubleshoot electronics (not electrical) hardware for a living. Dimming of Ye Lights: What Could Possibly Be Going Wrong?
  1. Wires are screwed down in a breaker panel, on the meter, and (I don't know how it works out to the pole..) and maybe up to the transformer on the pole. Any wire that's loose may have incidental contact most of the time, but run high current, the deltaV = R * deltaI, and there you are. The fun part: where in the (probably) three or five places that the current's passing through is the near-open? Additional fun fact: When Large Electric Motors start up, they often draw a lot of current, which then reduces as the motor gets up to speed. Yeah, AC compressor/blower motor, I'm looking at you!
  2. The above is straight electrical connections. Basic rule: If something can move, then it's more likely to break. That includes breakers. Most breakers of which I'm aware have a heat-sensing element that expands when Too Much Current flows, tripping the thing. There are others that use teeny magnets in there, no heat. The heat guys flex under normal operation (i.e., when that blower starts up). Any flexing, over time, causes metal fatigue. It might take decades, but thermal breakers do wear out. Now, if the resident electrician on this thread thinks that the "normal" failure mode of such a failing breaker is simply to trip, far be it from me to argue: He's the expert. But then we're back to #1.
The problem with #1 above is Big Voltage Drops means Power Dissipation. And Power Dissipation means that Things Will Get Hot. In the electrical world in general, Hot Things are very much to be avoided. Now, nifty, short, droops.. I can make a half-a$$ argument that if it doesn't last too long, all those big copper conductors will carry the heat away. And the little guy screaming in the back of my head is going, "Until it Doesn't!" Don't risk your life and those of your loved ones please: Find out what's going on and Get It Fixed.

Finally: As I said, I'm not an electrician. But One Day, when helping a Real Master Electrician on a kitchen reno, we ended up replacing the breaker panel in the house I lived in at the time. I played the idiot assistant: Just competent enough to hand the Real Guy a screwdriver when asked. (He was my neighbor. Yes, I paid full freight.)

So, why were we replacing this breaker panel? Because it had been made by Federated Pacific. Who was Federated Pacific? A company whose breaker panels tended to catch on fire in the presence of an overcurrent or surge. And, after our reno, the house wouldn't get a certificate of occupancy unless that particular panel was gone, gone, gone.

One last thing. As the electrician was removing the individual breakers from said panel in prep to getting the whole thing out, he would reach over to unplug a breaker with one hand. Before doing the deed, he would then turn away from the panel, put his left arm over his eyes, then pull the breaker out. I watched him do this three times, at which point it occurred to me that if a Master Electrician was Doing That, why the heck wasn't I doing the Same Thing? And henceforth copied the man 😁.
 
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Hey @jcanoe, thank you so much for the information! This gives me a lot of confidence. I rarely drive; in fact, Model Y is my first vehicle. On average I drive about 20-40 miles a day and 60 miles at most.
This is an interesting thread (read it all) and I've picked up a good deal of useful information from poster comments. One thought I'd like to throw out. Using your MY at the useage amounts you state you might not need a 240v NEMA 14-50 outlet. Heresy I hear you say!! Hear me out.

A 120v outlet will give you around 3~4 miles of range per hour of charge using the mobile connector. If you are plugged in 20 hours a day then you will be putting in around 60 miles of range during a "normal" day's use.

I've survived using a 120v outlet for one of our two EVs and it worked out just fine (Bolt 2019, now replaced with a Tesla M3 SR LFP).

Bolt plugged-in to a 120v outlet (already installed in the ceiling was you see it when we purchased the home)

oak4MAm.jpg


Better view of EVSE ("charger") plugged into the outlet.
1Mwvxle.jpg


Our MY plugged into a NEMA 14-50 outlet using the mobile connector.
atVt5ak.jpg
 
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qdeathstar

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Sure, unshielded wire is not used in walls.
But in conduit its fine, right?
THHN in conduit was used in the installation of my EVSE in the garage. At the time, I did not consider AL wire. But it sounds like with a junction box, AL wire would have been a copper THHN replacement.

You can run that in conduit. But by the time you pay for the wire and the conduit and the extra labor to pull the wire through the conduit you are better off just using ser cable, from a price perspective…

.
In my mind, dimming of lights means the voltage has drooped.

Yes.

The voltage drooping is due to power lost in the wiring.

No. The voltage drops due to high resistance.

This could be due to undersized wires with a load which might match the circuit breaker. The current just needs to be high enough to cause excess power lost in the wiring. This doesn't necessarily mean the circuit breaker will trip.

Very unlikely. Your wire would have to massively undersized for you to notice power loss due to an undersized wire. Like 12 gauge wiring trying to pull 70 amps. That’s still only a 5 percent voltage drop over 50ft…

But before that your breaker would probably trip due to the heat generated pretty quickly. Breakers are thermally activated.
 
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qdeathstar

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This is an interesting thread (read it all) and I've picked up a good deal of useful information from poster comments. One thought I'd like to throw out. Using your MY at the useage amounts you state you might not need a 240v NEMA 14-50 outlet. Heresy I hear you say!! Hear me out.

A 120v outlet will give you around 3~4 miles of range per hour of charge using the mobile connector. If you are plugged in 20 hours a day then you will be putting in around 60 miles of range during a "normal" day's use.

I've survived using a 120v outlet for one of our two EVs and it worked out just fine (Bolt 2019, now replaced with a Tesla M3 SR LFP).

Bolt plugged-in to a 120v outlet (already installed in the ceiling was you see it when we purchased the home)

oak4MAm.jpg


Better view of EVSE ("charger") plugged into the outlet.
1Mwvxle.jpg


Our MY plugged into a NEMA 14-50 outlet using the mobile connector.
atVt5ak.jpg

Honestly you would still need that 120v circuit to be dedicated… so if you are going to run a 120v dedicated circuit, for the same exact price you can run a 240v circuit and charge twice as fast….
 
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You would want to leave the Mobile Connector plugged into the 14-50 receptacle. 14-50 receptacles are not designed for repeated plugging and unplugging. Also, Tesla sells a Cable Organizer that includes a wall mount bracket for the Mobile Connector. You want to mount the Mobile Connector chassis to the wall so that the weight of the Mobile Connector is not putting a strain on the receptacle and power plug. You can find similar wall mount brackets on Amazon, eBay and Etsy. You can also fashion your own support for the Mobile Connector chassis.
Good advice! I will look into a wall mount, thanks!
 
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One more thing about that mobile connector in the garage. The OP is in Chicagoland. Rumor has it that it gets cold out there at certain times of the year.

If the OP has a heated garage, all well and good. If it gets below freezing in there, charging can be compromised.

Yep, if everything’s at room temperature, then one gets that 5 mph charge rate at 120VAC. But if it’s below 45 or so and definitely if it’s below freezing, the car will heat the battery before charging the car. If it’s cold enough, the car won’t charge, or will charge at a minuscule rate. Like 1 mph. Or less. Speaking from personal experience.

At 240VAC, one gets enough power to get the battery warm, even at 15A, then one is off to the races.

You’ve been warned.
 
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Hard to say but the first option does not increase the power you have available. Ideally you’d upgrade to 200 amps. I don’t know how much that would cost… but depending on the age/condition of your panel it might need to be replaced anyway.

As far as installing the sub panel (second option) I don’t see why you’d do that. You only have a 100 amp service, you won’t be able to run anything out of the sub panel anyway.
Got it. Thank you so much for the input. The panel is indeed very old so I guess it is time to replace it. I confirmed with the electrician on the first proposal multiple times and he said there are enough loads for 50 AMP breakers, but just no space in the current panel. By the way, do you think that's a fair price for the first proposal?
 
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qdeathstar

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I do think it is a fair price. But I would ask him how much to upgrade. Honesty, I would charge 1450 to replace a 100 amp panel and 2450 to upgrade… it totally depends on your exact setup though. Most localities require permits so I would request permits be pulled. They should pull the permits.

It’s the best way to make sure the company is licensed….
 
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This is an interesting thread (read it all) and I've picked up a good deal of useful information from poster comments. One thought I'd like to throw out. Using your MY at the useage amounts you state you might not need a 240v NEMA 14-50 outlet. Heresy I hear you say!! Hear me out.

A 120v outlet will give you around 3~4 miles of range per hour of charge using the mobile connector. If you are plugged in 20 hours a day then you will be putting in around 60 miles of range during a "normal" day's use.

I've survived using a 120v outlet for one of our two EVs and it worked out just fine (Bolt 2019, now replaced with a Tesla M3 SR LFP).

Bolt plugged-in to a 120v outlet (already installed in the ceiling was you see it when we purchased the home)

oak4MAm.jpg


Better view of EVSE ("charger") plugged into the outlet.
1Mwvxle.jpg


Our MY plugged into a NEMA 14-50 outlet using the mobile connector.
atVt5ak.jpg
Wow, thanks for sharing. I really like the pictures too! I just wasn't sure if I want to 'risk' it because what if I began to drive a lot after the MY arrived? I heard model y is very fun to drive haha. Anyway, if 120v also works then it gives me more time to procrastinate on making a decision!
 
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One more thing about that mobile connector in the garage. The OP is in Chicagoland. Rumor has it that it gets cold out there at certain times of the year.

If the OP has a heated garage, all well and good. If it gets below freezing in there, charging can be compromised.

Yep, if everything’s at room temperature, then one gets that 5 mph charge rate at 120VAC. But if it’s below 45 or so and definitely if it’s below freezing, the car will heat the battery before charging the car. If it’s cold enough, the car won’t charge, or will charge at a minuscule rate. Like 1 mph. Or less. Speaking from personal experience.

At 240VAC, one gets enough power to get the battery warm, even at 15A, then one is off to the races.

You’ve been warned.
Yes, Chicago is very COLD. I never really consider this perspective so thanks for bringing this up! A 240V is definitely needed and I will work on that soon! Really appreciate all your input. I confirmed with the electrician who gives me the first proposal and he's confident that my panel could afford a 50 AMP breaker dedicated to the charger. I just need to swap the panel because the panel is very old and no rooms left as well.
 
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I do think it is a fair price. But I would ask him how much to upgrade. Honesty, I would charge 1450 to replace a 100 amp panel and 2450 to upgrade… it totally depends on your exact setup though. Most localities require permits so I would request permits be pulled. They should pull the permits.

It’s the best way to make sure the company is licensed….
He told me that the upgrade to 200 AMP will start around $6000 - 8000, but I don't know if that includes the power brought to the garage. If I were to take a guess, it would cost around $10, 000 for the upgrade plus the power brought to the garage.

Edit: I don't know whether my locality requires a permit. How do I check that? Do they need a permit if they just do the panel swap and have the power brought to the garage?
 
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brkaus

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He told me that the upgrade to 200 AMP will start around $6000 - 8000, but I don't know if that includes the power brought to the garage. If I were to take a guess, it would cost around $10, 000 for the upgrade plus the power brought to the garage.

Edit: I don't know whether my locality requires a permit. How do I check that? Do they need a permit if they just do the panel swap and have the power brought to the garage?
If you are in any municipality that work would very likely require a permit. You want one to protect you.
 
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