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So many mixed answers - Electrical requirements for installation

I've had 4 quotes so far, 2 of which were from Tesla recommended installers.
The non Tesla recommended electricians just gave me a price over the phone so I was no impressed, they did not want to come have a look in person.Both Tesla recommended installers came to see the job.
One of the Telsa installers said I need to upgrade my 100 amps panel to 200 if I want to add a 14-50 plug for a 32 amp charge.
My load calculator came out to 104 amps by both electricians but one says I need to upgrade, the other says the measly 4 amps over will pass inspection.
Obviously the latter is cheaper to install. The problem with my panel is that it's in my basement and fed from across the house, underneath the garage concrete floor with smaller than 200 amp conduit.
To make this 200 amps I was quoted $3000 alone for the upgrade.

What exactly should I do here and who do I go with? Please anyone who has been in a similar situation, please chime in.
is there some way to make my existing 100 amps panel a sub panel as I've read about this somewhere. Can the small conduit fit 200 amp cables?? They said the conduit is 1-1/4" feeding my existing panel.
 
I've had 4 quotes so far, 2 of which were from Tesla recommended installers.
The non Tesla recommended electricians just gave me a price over the phone so I was no impressed, they did not want to come have a look in person.Both Tesla recommended installers came to see the job.
One of the Telsa installers said I need to upgrade my 100 amps panel to 200 if I want to add a 14-50 plug for a 32 amp charge.
My load calculator came out to 104 amps by both electricians but one says I need to upgrade, the other says the measly 4 amps over will pass inspection.
Obviously the latter is cheaper to install. The problem with my panel is that it's in my basement and fed from across the house, underneath the garage concrete floor with smaller than 200 amp conduit.
To make this 200 amps I was quoted $3000 alone for the upgrade.

What exactly should I do here and who do I go with? Please anyone who has been in a similar situation, please chime in.
is there some way to make my existing 100 amps panel a sub panel as I've read about this somewhere. Can the small conduit fit 200 amp cables?? They said the conduit is 1-1/4" feeding my existing panel.
You can keep your current panel but just set it up as lower than 32amp.. unless you want to spend $3k for an upgraded panel. It will help with the value of your house though so it’s not necessarily a waste.
 
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Where is your electrical meter? On the garage? If so, you could install a 200A panel in the garage where the existing 100A wire from the basement panel wire will reach (ie: probably where the where the wire goes out through the wall to the meter). Then the 100A panel can be fed off a 100A breaker in the new garage panel. Then add your 50A plug off the 200A panel directly in the garage. Or install a 60A circuit directly to a HPWC since you would have the capacity in the new panel and I assume the cable length would be quite short.

It would still cost a bit, as the utility has to get involved to pull the meter for the upgrade.

Or as suggested above, install a smaller wire/breaker from the existing panel to keep you under the limit for your existing panel. They may not want to install it on a 14-50 receptacle though. So either install a receptacle rated for the lower rating (20 or 30A), or wire in the HPWC directly without the receptacle. Either way, set the charge limit switch to the appropriate lower rating.
 
I've been in a similar situation - my load calculation was slightly over and ESA would not pass it - contractor thought they might based on past experience but it was a different guy that day.

Rather than the service upgrade to 200 amps which would have been several thousand, he installed a "charge controller" on the feed from the panel. This is ESA-approved and disconnects the charger if the panel load is too high - I'd have to look to be sure but I think it was $600 or $800. It's tripped twice - both in summertime with AC and electric dryer running, which is the idea. It switches supply back on once the house load reduces. It's really no hassle and recommended as an option to avoid expensive upgrades.
 
Similar situation - existing 100A panel in the basement. I opted to install a new 200A panel in the garage off the meter feed, and then feed the old 100A panel from a 100A breaker (using the existing outside line). Then the electrician installed a 60A breaker to the HPWC. This is the 'ideal' configuration for the Model 3 with no compromises. This future-proofs the install in case we ever get a second EV; or we upgrade to a model that supports 80A+ charging in the future.

Generally you don't need the full charging rate. But there have been a couple of times during the winter where we've arrived home after a road trip with < 60 km range remaining and we needed the vehicle later in the day. A couple hours on the charger and we're back up to 200+ km. We consistently get +71 km/hr charging rate with this setup.

The whole thing including the HPWC install cost around $2400 ($1800 for the panel install, $600 for the HPWC).
 

linkster

Active Member
Apr 22, 2013
1,128
277
USAX2
What model Tesla are you purchasing (since they replenish miles at different rates)?
What is your normal RT commute?

I deployed a 14-30 for approx 5 years with a mostly 80-mile RT commute so that I could almost recover the miles burned in a 4 hr. (1a - 5a) window to take advantage of $.05 -.06 kWh pricing. I have moved and now charge both the S (12mph) and 3 (15mph) with a lowly 6-20.

Might you be able reduce the branch circuit capacity for charging to suit your driving needs and still fall inside your load calcs so as not to unnecessarily drop $3K?

Good luck!
 
No way you're using more than 60A over night. I'm charging at 32A (40A *0.8) for the past seven months off a 100A panel for a 3bed house. I'm lucky though to have a sub panel already in the garage with a welder's plug. Ask to install a NEMA 14-50 tied to a 40A breaker, should be fine.

This is the best course if not upgrading panel. You set your charge for 32-40amps either/or at 1:30am. There is no way your using that much energy anywhere in your home at that time of the night assuming you do not have electric heat or electric water heater or Heat pumps and swimminging pool and Irrigation pumps etc. With 100 amps to house you must not have those items.

Upgrading the panel though is the best choice all around and not only if other Tesla's/electric cars are planned for the future.
 

jerry33

(S85-3/2/13 traded in) X LR: F2611##-3/27/20
Supporting Member
Mar 8, 2012
20,820
29,738
Texas
To make this 200 amps I was quoted $3000 alone for the upgrade.
That price appears to be typical for the work proposed. I'd base the decision on who made the 100 amp panel. If it's Federal Pacific or Zinsco, do the replacement--this is a no-brainer. They have serious issues with the breakers not tripping. $3K is cheaper than a house fire. If it's some other brand, be sure to check to see if there are any safety concerns.
 
Where is your electrical meter? On the garage? If so, you could install a 200A panel in the garage where the existing 100A wire from the basement panel wire will reach (ie: probably where the where the wire goes out through the wall to the meter). Then the 100A panel can be fed off a 100A breaker in the new garage panel. Then add your 50A plug off the 200A panel directly in the garage. Or install a 60A circuit directly to a HPWC since you would have the capacity in the new panel and I assume the cable length would be quite short.

It would still cost a bit, as the utility has to get involved to pull the meter for the upgrade.

Or as suggested above, install a smaller wire/breaker from the existing panel to keep you under the limit for your existing panel. They may not want to install it on a 14-50 receptacle though. So either install a receptacle rated for the lower rating (20 or 30A), or wire in the HPWC directly without the receptacle. Either way, set the charge limit switch to the appropriate lower rating.

Hi thanks for posting. Did the electrician have to add any wire to the 100 amps pipe to do this? He told me that to do that he would have to add 1 more wire to the pipe going to my 100 amp panel to make it into an auxiliary panel and hat this may not fit into the pipe.
 
I've been in a similar situation - my load calculation was slightly over and ESA would not pass it - contractor thought they might based on past experience but it was a different guy that day.

Rather than the service upgrade to 200 amps which would have been several thousand, he installed a "charge controller" on the feed from the panel. This is ESA-approved and disconnects the charger if the panel load is too high - I'd have to look to be sure but I think it was $600 or $800. It's tripped twice - both in summertime with AC and electric dryer running, which is the idea. It switches supply back on once the house load reduces. It's really no hassle and recommended as an option to avoid expensive upgrades.

Hi do you have anymore information about this? What was the cost to do the work? Do you have any pictures? brand and model of this "charger controller"?
 
Similar situation - existing 100A panel in the basement. I opted to install a new 200A panel in the garage off the meter feed, and then feed the old 100A panel from a 100A breaker (using the existing outside line). Then the electrician installed a 60A breaker to the HPWC. This is the 'ideal' configuration for the Model 3 with no compromises. This future-proofs the install in case we ever get a second EV; or we upgrade to a model that supports 80A+ charging in the future.

Generally you don't need the full charging rate. But there have been a couple of times during the winter where we've arrived home after a road trip with < 60 km range remaining and we needed the vehicle later in the day. A couple hours on the charger and we're back up to 200+ km. We consistently get +71 km/hr charging rate with this setup.

The whole thing including the HPWC install cost around $2400 ($1800 for the panel install, $600 for the HPWC).

Hi same as quoted above. Did the electrician have to add another wire to the 100 amp pipe?
 

rypalmer

Active Member
Aug 22, 2014
1,605
1,847
Canada
The real question should be: how much do you drive? This as much as anything should dictate how much current you try to allocate to a charger.

I have only a 24A service currently and I can tell you the car has no problem being fully charged at all times, given how much I drive in Toronto.

Then again, I really appreciate thr 48A I have at home on PEI, but that was more about future-proofing an underground service.
 
Hi same as quoted above. Did the electrician have to add another wire to the 100 amp pipe?

They used the original wire from the meter to the 100A panel to drive the new 100A subpanel circuit. This probably kept the cost down somewhat. It may not be possible in all configurations depending on where the new panel is going. In my case the new panel is literally on the other side of the garage from the meter so it worked well.
 
I'll just add another 24A service to the car is more than enough. At my condo building, that's all we could install, and it's fine. If there's ever a time that I arrive near empty and need to go out in a few hours, there's always supercharging. In my MX75D that gives me about 5% of charge per hour. So 14 hours to charge 70%. That's more than enough for most drivers.
 
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I'll just add another 24A service to the car is more than enough. At my condo building, that's all we could install, and it's fine. If there's ever a time that I arrive near empty and need to go out in a few hours, there's always supercharging. In my MX75D that gives me about 5% of charge per hour. So 14 hours to charge 70%. That's more than enough for most drivers.

I don't think that 24A is a good experience for people in the winter. Too much current is drawn to warm the battery during charging. The charge rate will simply be too slow. I don't see much point in cheaping out on your personal charging infrastructure for a $60k+ vehicle. May as well go with at least 32A or ideally 48A max for Model 3. The condo situation may be different in a heated or at least non-freezing garage.
 
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When thinking about a service upgrade, keep in mind that Toronto Hydro (if you're in Toronto) charges $600+tax for service disconnect/reconnect. This is likely above and beyond what your electrician is quoting.

If you're planning on staying in the house for a while, it may be worthwhile upgrading your electrical service. In addition to giving you some breathing room for future EVs or other increases in electrical demands, it's also good for resale.
 
Hi do you have anymore information about this? What was the cost to do the work? Do you have any pictures? brand and model of this "charger controller"?

It cost me $1100 taxes in for everything. That was vs $5000 to upgrade to 200 amps (in my case - there are many factors that can affect this price like distance to panel, Hydro One fees etc - I got unlucky I think).

The charge controller is this one - DCC-10 Avoids Major Home Electrical Upgrades for an EV Charging Installation. Works great and ESA approved. Going over your calculated load allowance is against code and potentially unsafe so I'd be wary of any suggestions you'll be OK if your calculation is "close".
 

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