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HPWC install story, flush subpanel, no free slots

Hello TMC folks and kind knowledgeable electricians and DIYers,

TLDR
If my panel has existing code issues, would it hinder inspection for a 240V addition?
Can I add a quad breaker to the top left two slots of a Homeline panel?

Long form:
I want to share my HPWC install story (ps not sure if this is the right place since charging is not MY specific), in case it may be of help to anyone, and get some feedback on my panel situation before I make the final hookup.

This is an indoor garage install, from a flush mount panel out to exposed conduit. I haven't connected it yet but am at the final stage.

I picked up my black MYP late December (hell effing yes I love it!!).

Here's the basic supplies
Wires: #6 THHN (blk/red) and #10 bare copper
Conduit: 3/4" EMT, 90 deg bends, couplings, half saddle brackets, offset connectors (no bending, only hacksaw cuts)
Conduit (in wall): 3/4" flex liquid tight PVC, chunky 'easy' connectors (straight and 90 deg)
I suppose 4/3 (4/2 doesn't exist?) romex would work here in wall, and skip the conduit, but I couldn't find it by the foot, and would need to make connections in the jbox
Breaker: Square D 2020250 quad breaker (takes two slots, provides two 20A single pole and one 50A double pole circuit)
I wanted a 60A circuit, but my panel was full. This will suffice for now as I want to add solar in the future and don't want to upgrade too much in terms of electrical now.​

I had pondered how to get a circuit out of a flush mount panel even before owning an EV. There are good videos, but took a while to find. This one I like in particular (ymmv):
https://www.youtube.com/watch?v=5ip38Mf093Y&t=836s&ab_channel=TheHonestCarpenter

The process (I'll post some pics of the process later)
Mounted the base of the HPWC, started mounting conduit up and across the wall to the top of the panel.
Selected a punch out on the panel top, aligned the junction box target location
Pushing a flexible camera up from the panel, I felt some resistance - using a stud finder I found a horizontal piece impeding the way (arrgh).
Opened up a piece of drywall above the panel to get a drill and spade bit in there and open a 1" passage for the flex conduit​
My largest bit was 1", used a rotary tool grinder bit to open it up some more to get the flex PVC through​
Opened a small square above for entrance into the jbox, now I could push up the flex PVC and tug it out the top to attach a 90 deg connector
Cut the bottom of the PVC to length, attached a connector and connected to the panel.
These connectors are bulky and hard to work with behind a wall, but easy to attach, no glue etc, I had to adjust the length a couple times so they helped​
I stagger taped the wires and pushed them through, leaving the second 90 deg bend open. Once they made it, I added the last leg of conduit and pushed to the jbox
One note: the offest connectors have a larger offset than both the HPWC base and my square jbox. Starting from the HPWC this didn't matter, but it off my measurements at the end jbox. However, with a little adjustment at the last bend I could keep the last run of conduit level.

So now to my three questions
My panel is a bit of a mess, it's a Homeline panel, but I see Type MH-T breakers with double wires in it. I want to get a permit, but I'm concerned the existing issues may cause problems during an inspection?

I want to replace the two top left 20A breakers with the quad breaker. Will the top left two slots accept a double pole (actually quad) breaker? I vaguely recall reading that double pole breakers can't be installed in just any two slots.

Finally, the cover is a 20 slot, but the guts are 12 slot (arrrghh). I wan't to replace the guts to get more space (it's fed by a 100A from the main panel). what say the pros?
D1D5176E-0EBA-4451-9486-C30803F21608_1_105_c.jpeg

Thanks in advance for replies and advice.
 

Madsen203

May 26, MYLR, White ext, Black int, Tow, 19”
Jun 1, 2021
727
527
Bay Area
Your install looks pretty clean. I hate conduit but running through studs every 16” would be painful. I would prime and paint it when you’re done.

I repurposed a breaker that wasn’t being use and was able to find smaller breakers that fit the panel. I technically don’t meet NEC as the power pulled is greater than the allowed threshold. Alas, it never runs all the heavy equipment at once so there hasn’t been an issue since.
 
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ATPMSD

Active Member
Mar 12, 2021
1,460
1,372
Atlanta, GA
What is the breaker rating that is servicing this panel?

Update: I see where this is a 100 amp feed. Most electricians will not install more than a 30-amp 240v line in such panel, so you should probably forget the 60-amp desire. I bet an inspector would fail you if you used anything bigger than 30-amps - just a guess.

50-amp is likely too much as you are only allowed to pull 80-amps continious and the wall conector on a 50-amp circuit it is going to pull half of that, but you can give it a try. If the main breaker trips, or if the car will not hold the specified charge rate (which indicates a voltage problem), then dial down the wall connector to 40-amps, and then 30-amps if need be. Once you find a setting that works replace the breaker if a lower limited is needed.

Yes you can avoid running other equipment when the car is charging, but that is not a good idea when it comes to power.

Good luck!
 
Last edited:
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Reactions: treemanzarek
Your install looks pretty clean. I hate conduit but running through studs every 16” would be painful. I would prime and paint it when you’re done.

I repurposed a breaker that wasn’t being use and was able to find smaller breakers that fit the panel. I technically don’t meet NEC as the power pulled is greater than the allowed threshold. Alas, it never runs all the heavy equipment at once so there hasn’t been an issue since.
Thanks, I plan to paint the conduit. It's the garage so, I'm ok with it exposed.
 
What is the breaker rating that is servicing this panel?

Update: I see where this is a 100 amp feed. Most electricians will not install more than a 30-amp 240v line in such panel, so you should probably forget the 60-amp desire. I bet an inspector would fail you if you used anything bigger than 30-amps - just a guess.

50-amp is likely too much as you are only allowed to pull 80-amps continious and the wall conector on a 50-amp circuit it is going to pull half of that, but you can give it a try. If the main breaker trips, or if the car will not hold the specified charge rate (which indicates a voltage problem), then dial down the wall connector to 40-amps, and then 30-amps if need be. Once you find a setting that works replace the breaker if a lower limited is needed.

Yes you can avoid running other equipment when the car is charging, but that is not a good idea when it comes to power.

Good luck!
Thanks, I am starting to feel like a 50A addition may not pass official load limits. Bummer, but I'll try it out a derate it down if needed like you suggested.
 

Madsen203

May 26, MYLR, White ext, Black int, Tow, 19”
Jun 1, 2021
727
527
Bay Area
Are people really pulling permits and getting inspections on EV wall connectors? I just added it myself. Added a 50amp breaker on a 100amp sub panel and I also run a hot tub, laundry, and household appliances and never had an issue or trip the main breaker. Sure, it’s against the recommended NEC code but the reality is the WC will drop voltage if needed or you can time to not use AC early morning when your car is charging.
 

ATPMSD

Active Member
Mar 12, 2021
1,460
1,372
Atlanta, GA
Are people really pulling permits and getting inspections on EV wall connectors? I just added it myself. Added a 50amp breaker on a 100amp sub panel and I also run a hot tub, laundry, and household appliances and never had an issue or trip the main breaker. Sure, it’s against the recommended NEC code but the reality is the WC will drop voltage if needed or you can time to not use AC early morning when your car is charging.
Just because you can do something does not mean you should. The NEC code was created for a reason. Of course you can disregard it.
 
Are people really pulling permits and getting inspections on EV wall connectors? I just added it myself. Added a 50amp breaker on a 100amp sub panel and I also run a hot tub, laundry, and household appliances and never had an issue or trip the main breaker. Sure, it’s against the recommended NEC code but the reality is the WC will drop voltage if needed or you can time to not use AC early morning when your car is charging.
Insurance companies are always happy to find a reason not to pay out. If your municipality requires inspections and you don't do it, you'll be in a bad place if there's an incident.
 
I want to replace the two top left 20A breakers with the quad breaker. Will the top left two slots accept a double pole (actually quad) breaker? I vaguely recall reading that double pole breakers can't be installed in just any two slots.
Yes that’s always been my understanding. It’s usually marked on the panel sticker for which spots you can install dual poles if you even can. My panels I think all say they need to be in the bottom 6 or so. Good job on the inside conduit run, it is a daunting task. Make sure you put the locknut on, inspectors love to fail people for missed bushings.
 
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You may be able to add a larger buss bar kit to your panel to match the cover. There is a sticker in your panel that will let you know the max size you can run. That should let you run a standard dual pole breaker and generally make it easier to clean up the panel. FWIW I think you're fine running a 60a breaker in there if you schedule charging for late night. A cheap amp meter will help you understand what is going on in your panel a lot better.
 
Insurance companies are always happy to find a reason not to pay out. If your municipality requires inspections and you don't do it, you'll be in a bad place if there's an incident.
This ^^^

And, I live in a high fire danger area, I don't want to sweat because of a $200 permit if the worst happens.

(although if there's a wildfire (i.e. not electrical), would anyone care? because of course I would rather just plug in the new breaker and not go through the hassle, but I probably will)
 

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