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I live in a condo. The main breaker is only 70A. Now what? [Resolved]

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The 70A breakers are underneath those black panels next to the meters. Trust me, they're there.

Yes, I'm a bit panic'd but IMHO, justifiably so. The issue here is the $2,500. There is no need for me to gamble with that kind of money until I determine one way or another how difficult of a job it will be to upgrade the main breaker from 70A to 100A.

My plan is to cancel the order, then have a few electricians come out and inspect the property after I return from my trip. With any luck I'll be able to upgrade the main breaker to 100A, update the panel in my garage and install a 14-30 outlet on a new breaker. I'm sure Tesla would have no problem whatsoever restarting my order...
I cannot see the logic behind canceling the order and then have few electricians come out... If you still want to electricians to do something, what the point to cancel order before that? You can cancel order after electricians offers anyway. But honestly, I would just go with that electrician who made you offer to install 30A 240V outlet. Do not make a big deal of it, just get the job done and get your Tesla before the end of the year.
 
That panel is certainly maxed out.

You could do 2 things.

Replace that sub panel with one with more slots. Same amps. It should NOT cost that much.
I think you could get away with adding 20 amp 240V (maybe even 30 240V amp).
Even a 15 AMP 240 would be way better than 120V at any amps.

You could add a Sub Panel off that one and move some circuits over to the new subpanel but that would probably be as much work and not nearly as clean. Could also plan ahead and use a higher Max Amp panel (100-150 AMP) but with a 70AMP main. So that you could upgrade the service in the future.

I think 120V is not an option, unless it's an emergency. It's inefficient and slow as molasses (3-4 miles/hr).

Keep in mind a lot of appliances are "Peak or Surge" loads. The ratings are not continuous.
Sometimes they list both on the load.

One other sleazy thing you can do is double up some circuits. You'd have to go through what's really on each. I've seen circuits dedicated to a doorbell transformer. You'd have to double up 4 circuits though, which is a lot.

P.S. If you want to help the planet get rid of that 1989 HVAC ;)
 
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Hey all-

Just tuning into this thread. I have a lot of thoughts here:

1. I don't know how bad the Challenger panels are. I know Zinsco and Federal Pacific and Challenger are all on the "bad" list, though I believe some of the issues were with bad breakers and other issues were with bad panels in addition to bad breakers. There are 3rd parties that sell new breakers for Challenger panels that are presumably safe today (but I don't know if the underlying panel might still have issues).
2. Knowing what I know now and with the skills I have, I likely would replace that panel inside your condo with a new one regardless of any EV project. The actual parts are stupid cheap for such a simple panel. Like maybe only a couple hundred bucks? Since it is inside your unit and presumably owned by you, I don't think the HOA could have anything whatsoever to say about it. I would install a new one that was capable of at least 100a or 125a (if not a full 200a).
3. Can you take the cover off that panel and take detailed pictures? I need to know what size (AWG) of wire feeds it, whether it is copper or aluminum, and what kind of wire it is (SE wire, THHN, XHHW, etc...) - I am wondering if it is in conduit all the way back to the main panel - it looks to me like the four units that feed out of that main panel are in flex conduit going down out of the panel and so if you are really lucky it might be conduit the entire way (like underground). If so, we need to know what size the conduit is. It is possible that say the existing wire is aluminum and that you could just pull in new copper wire with a higher ampacity into the existing conduit (or simply larger gauge wire than the previous wire but in the same conduit). Also, please post a detailed picture of the sticker on the door to your existing panel. I need to verify which breaker types are allowed in the panel.
4. The HOA board should have capital reserve funds for projects like replacing those main electrical panels - this is a longer time horizon project probably, but if those panels are deemed unsafe then the HOA board is obligated to replace them (assuming they own them which I am sure they do as they are common services). 70a per unit is simply not enough for modern needs. (note that the future involves us stopping burning natural gas too and so more things will shift to electric)
5. If a licensed and insured electrician is willing to add a 30a 240v receptacle for you off that existing panel and they are able to find you a breaker to do it with your existing panel, then I might be tempted to do it. The install should be relatively inexpensive as it is such a short run and getting "something" to tide you over is the most important thing right now. I am not sure if anyone makes a Challenger compatible quad pole tandem breaker that is 30 + 30 @ 240v each. That would be the only way to add another 30a circuit I think (double up the AC breaker). Note that Eaton cross-rates their breakers to work in a huge range of other manufacturers panels, but I am unsure if the Challenger ones are compatible.
6. Doing a transfer switch on the AC unit is not a horrible idea. That would certainly solve the breaker issue and load calculation issue. Though I would not want to put an EV load on a questionable breaker if indeed your Challenger breakers are potential hazards. I might swap the breaker out with a modern replacement at the time I did this (if not swapping the entire panel). Though you will need hours of charging a night (depending on your driving needs) and I personally would not want to be without AC. Actually, how many miles a day of driving do you need to plan for? We should have started there.
7. I would probably in addition to replacing the panel, I would get a Sense home energy monitor (I have one). This would let you track your usage to see how close to that 70a limit you get. My guess is your loads are pretty light. I would absolutely not want to live long term with only a 70a feed - your HOA needs to come to grips with that - folks are going to need upgrades as EV's become mainstream!
8. I am also a massive fan of the Wall Connector. If I replaced the panel I would probably put say a 50a breaker in the new panel and wire a Wall Connector up with sufficient ampacity wire for say at least a 60a circuit (48a usable). Then I would set the Wall Connector down lower (using the rotary dial inside) than the full 50a circuit allows for in order to stay within load calculations. In the future when you finally get a 125a feed to your unit (or whatever) you could just dial it up as needed (and maybe swap the breaker up to a 60a breaker). A huge value of the Wall Connector is that it has small increment steps so you can dial in how much calculated load you have available.

Please don't let this scare you away from owning an EV! You are so close! I *love* my Tesla M3! I went overkill (because I could) and installed a 60a circuit and a Wall Connector. I only have a 30 mile commute total round trip. My car charges in an hour every night when I get home. It is insanely fast and overkill. Even 20a (16a continuous) at 240v might be sufficient for your climate and driving habits!

Note that I need to call out that some have mentioned charging at night means things won't be an issue, but this is not how code works. NEC does not rely on layman humans to provide safety by remembering to set the charge timer. It assumes the users are not capable of avoiding overload situations. Doing load calculations is one layer of safety and the actual overcurrent devices are another layer of safety.

Check out this panel you could replace yours with:

Eaton BR 125 Amp 12 Space 24 Circuit IndoorMain Lug Loadcenter with Cover Value Pack (includes 5-BR120)-BR1224L125V1 - The Home Depot

It has 12 positions vs. the eight you currently have. Each one is rated for "tandem" breakers which means you could have up to 24 circuits. It is rated to be fed with up to 125 amps of feed capacity in from that main panel. $42.95 including five 20a 120v breakers! (though you only need three currently) That is insanity cheap. Unbelievable. If I were you I would go out and buy that panel (or I might even buy a larger / higher capacity one than that) and replace your existing panel today. Zero reasons to have any safety concerns with the panel in your house. That looks like probably just a few hours for a professional to swap.

Good luck! Please report back! (and have a great trip!)
 
Hi, I'd like to take the oportunity of this discussion to evaluate the possibility
to get a 20-30A Nema 14-50 plug installed from my main 60 A breakers in my building garage.

20181014_215041.jpg

The building has a 3 phase 600 A input and there are 30 units.
Each unit has a 2-phases 60 A breaker above each Meter.

There is a 240 V electric range oven in each unit.
The building has 3 washing machines, 3 gas dryers and an elevator.

20181014_215102.jpg

I would like to get the Nema 14-50 plug installed inside a locked switch box with fuses.
The switch box should be installed near the main panel. I will then plug the EVSE when needed.

So if I move out, there will be only a locked box with a plug inside.
I don't think that I would have to remove or unistall anything.

ge-electrical-disconnects-tg3221cp-64_1000.jpg ge-electrical-disconnects-tg3221cp-4f_1000.jpg

I am wonder if an electrician would be allowed to work on the main panel or if only my Electric company is allowed to do so?

My concern is to know if I would be able to get a connection from my braker allowing using my current Meter
or if a separate meter would have to be installed?
 
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Hi, I'd like to take the oportunity of this discussion to evaluate the possibility
to get a 20-30A Nema 14-50 plug installed from my main 60 A breaker in my building garage.
Talk to an electrician - you need a load analysis. 6-15 or 6-20 could be an option to add to your existing panel.

Another option could be another meter - then you could put in a 14-50. Or upgrade your service and replace your panel.
 
@andy92782
You need an electrician to tell you what size wiring you have to the subpanel. They may be rated for 70A max, 56A (80% load) sustained. If wiring is sized for 100A, maybe an inexpensive upgrade is possible. The panel and breakers are the smallest problem, those can be replaced relatively easily - existing wiring and available load capacity are your biggest challenges.

If you cannot upgrade, look into smart charging (charging which automatically senses how much your house is using and throttles the car charging accordingly - there are L2 solutions out there, even one which is supposed to work with Gen2 Tesla HPWCs, I can't recall the name but I saw it here on TMC). With smart charging, you car slows down when your AC and/or appliances are operating, and speeds back up when they stop.
 
Hi, I'd like to take the oportunity of this discussion to evaluate the possibility
to get a 20-30A Nema 14-50 plug installed from my main 60 A breakers in my building garage.

View attachment 344023

The building has a 3 phase 600 A input and there are 30 units.
Each unit has a 2-phases 60 A breaker above each Meter.

There is a 240 V electric range oven in each unit.
The building has 3 washing machines, 3 gas dryers and an elevator.

View attachment 344024

I would like to get the Nema 14-50 plug installed inside a locked switch box with fuses.
The switch box should be installed near the main panel. I will then plug the EVSE when needed.

So if I move out, there will be only a locked box with a plug inside.
I don't think that I would have to remove or unistall anything.

View attachment 344027 View attachment 344026

I am wonder if an electrician would be allowed to work on the main panel or if only my Electric company is allowed to do so?

My concern is to know if I would be able to get a connection from my braker allowing using my current Meter
or if a separate meter would have to be installed?

Modifying your building’s main electrical panel isnt going to be easy. I personally wouldn’t bother. Just use your own personal 60A panel. Use a specialized EV load miser for this situation. DCC Technology - Energy Management System for Electric Vehicle DCC CONDO AND DCC HOME
 
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Modifying your building’s main electrical panel isnt going to be easy. I personally wouldn’t bother. Just use your own personal 60A panel. Use a specialized EV load miser for this situation. DCC Technology - Energy Management System for Electric Vehicle DCC CONDO AND DCC HOME
Didn’t know that was available in the IS. Thanks!

I do hope the eventually make a version that works directly with the WC/HPWC. It should be able to throttle the WC down using the communications port. If that fails open the relay.
 
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I'm wondering why 240v 20 amp is not viable. This would use a 6-20 socket which would provide 16 amps, or 15 miles per hour charging. It can recharge 150 miles in 10 hours, or a full charge in 20. Even 15 amp service at 240 is not that bad as long as the daily commute is not too far.

I echo this. I currently charge through a normal 120V and it is fine for my purposes and probably most people’s. It may not be the BEST solution for most people but it works — I consistently get 5 mi/hr which translates to over 15,000 miles per year charging 8 hours per night and a few extra hours on weekends. Since I’ve had my Model 3 I have put on 3800 miles in a little over 3 months with no major issues so far.

A small upgrade in charging to get 150 miles charging in 10 hours as @CapnLoki suggests is more than adequate for almost everyone. Assuming 8 hours of charging a night (conservative) and 4 extra hours on weekends means you can charge 50,000 miles per year. And with 315 miles range you have plenty of cushion for back to back busy driving days.

NEMA 14-50 is great but it is not a “must have” for reliable charging for most people, especially with a Model 3 which is extremely efficient.
 
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You don’t need to upgrade your panel.

Since the panel is questionable because it's a Challenger, I'd want to upgrade it regardless. New panels are not expensive. Fires from breakers that overheat, or never trip are! Charging an EV will find all faults with a building's wiring.

Even if you don't replace the panel, I'd want to cut off power to it and remove each breaker for inspection.

I'm wondering why 240v 20 amp is not viable.

2x on this. A 20a breaker will give you 16a of charging. From time to time we charge our Model 3 on a 15A, 240v EVSE, and it's more than enough to make up for a day's drive when plugged in overnight. Have a NEMA 6-20 installed in your garage, and get the mobile connector adapter for it.

-J
 
Didn’t know that was available in the IS. Thanks!

I do hope the eventually make a version that works directly with the WC/HPWC. It should be able to throttle the WC down using the communications port. If that fails open the relay.

Has anyone hacked the HPWC communications yet? I don’t think the protocol is published. Making an electrical product that makes use of an unpublished API strikes me as, well, uncertifiable anyways.
 
Modifying your building’s main electrical panel isnt going to be easy. I personally wouldn’t bother. Just use your own personal 60A panel. Use a specialized EV load miser for this situation. DCC Technology - Energy Management System for Electric Vehicle DCC CONDO AND DCC HOME

OP here. This is an interesting gadget. Could be a possibility. No distributors for it in my area. That sucks... you think they’d be serious about having a presence in one of the biggest markets for EVs in the US.
 
5. If a licensed and insured electrician is willing to add a 30a 240v receptacle for you off that existing panel and they are able to find you a breaker to do it with your existing panel, then I might be tempted to do it. The install should be relatively inexpensive as it is such a short run and getting "something" to tide you over is the most important thing right now. I am not sure if anyone makes a Challenger compatible quad pole tandem breaker that is 30 + 30 @ 240v each. That would be the only way to add another 30a circuit I think (double up the AC breaker). Note that Eaton cross-rates their breakers to work in a huge range of other manufacturers panels, but I am unsure if the Challenger ones are compatible.

I never knew they made tandem 2 poles. Look here. Remove 30 Amp 2 Pole and put this in and you now have a 20 Amp 240 Circuit for EV.

Eaton BQ220230 Double Pole Quad Circuit Breaker, 20-30 A
Google Express
 
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Has anyone hacked the HPWC communications yet? I don’t think the protocol is published. Making an electrical product that makes use of an unpublished API strikes me as, well, uncertifiable anyways.

Yes, @CDragon -

https://teslamotorsclub.com/tmc/threads/new-wall-connector-load-sharing-protocol.72830/

There is also a company in Germany that sells a power / solar balancing system.

Regarding certification, I would think the relay would have to be there if the communication didn’t work.