Opinions Needed on Electrical Panel to Set Up Charger

[Sophias_dad]

The breakers you'd be looking for are called MH-T Quadplex, and here's an example.

https://store.usesi.com/murray-mp230240ct2-plug-in-mount-type-mh-t-quadplex-circuit-breaker-2-pole-30-amp-outer-and-2-pole-40-amp-inner-120-240-volt-ac-68301

You really should be talking to an electrician locally. I notice there's a * next to MH-T on most of the panelboard breakers column, which means 'MH-T 15-40 amp only' per the left area, and I interpret that to be any of the types from 15-15(if the make it) up to 40-40, which they probably don't make.

Your panelboard main breaker is an MP-T.

Note that Siemens bought or otherwise absorbed Murray a while back, so there's a Siemens equivalent to all(or almost all) the listed breakers.

 

[boulder.dude]

We did a remodel and they added a new main panel “in front of” our old (1970s) main panel, essentially turning it into a sub panel on a 100A breaker.

Then they put in a 60A breaker in the new main panel for the EV on a dedicated circuit to the garage.

Maybe this would work?

 

[Stanlana]

I wouldn't be super surprised if you can't even get another 32 amps out of that panel (putting a 40 amp breaker on a 14-50 is allowed). You NEED to get a load calculation done.

Here's an example of how you'd shoehorn another breaker in there...

Square D Homeline 2-30 Amp 2-Pole Quad Tandem Circuit Breaker HOMT230230CP - The Home Depot

The Square D by Schneider Electric Homeline Quad-Pole Tandem Circuit Breaker consists of (2) double-pole 30 Amp breakers. These innovative circuit breakers help free valuable load center spaces by combining

www.homedepot.com

https://images.thdstatic.com/catalog/pdfImages/04/044287a5-eca0-46c4-8239-809c47c3d388.pdf

Note that that breaker is only an example, and may not fit your panel at all. We don't know your panel model/maker, so I can't get more specific. Assuming that style fits, I see there are 30/40 and 30/50 pairs available.

Also note that the panel itself MIGHT not allow any more circuits. We won't know until there's a picture of the model/installation info(usually inside the door).

We did a remodel and they added a new main panel “in front of” our old (1970s) main panel, essentially turning it into a sub panel on a 100A breaker.

Then they put in a 60A breaker in the new main panel for the EV on a dedicated circuit to the garage.

Maybe this would work?

Thank you everyone, I will talk to electrician or two and see what they can do.

 

[Sophias_dad]

Thank you everyone, I will talk to electrician or two and see what they can do.

Note that that panel is actually rated for 125 amp service. Have the electrician see if the feeder wire and electric company will support 125, and you could have 25A more capacity with just a main breaker change.

 

[Vaildriver]

I'm probably using the wrong terms, but we had an electrician out to take a look at our setup for a home charger. They are recommending going from the outside box (meter main line) and then to a new breaker before being hard-wired into our charger. This would bypass our standard breaker box that is also located in the garage but a bit of a further run then the direct route noted above. Anyone had an electrician recommend jumping from the main line to something like this?
We have 2 other companies coming out to give us recommendations as well...

 

[bo3bdar]

Thank you everyone, I will talk to electrician or two and see what they can do.

Definitely talk to an electrician to get a good value for the load calculation for your personal situation. Based on the discussion here, it looks like you are already on the edge of being overloaded. If you have to add more service it will get pricey pretty quick.


Given that- consider if you actually need to install an L2 charger at all? The car comes with the 120V mobile charger, but you can use it just as well for daily charging, which is what I do.

As I mentioned earlier, the real question to answer is "how fast does it need to charge?" You can charge overnight at 120V without having to do any electrical changes, and just use a normal 120V outlet. You can get roughly 50 miles of charge overnight from 120V. If your daily drive is less than that, then you don't need to do anything special, and can just charge off 120V.


I'm in a similar boat, if I were to add an L2 charger of any form, I'd need to replace my electrical panel and upgrade to 200A service. This is on the order of $10,000 here in CA. Rather than do all that, I just charge over multiple days during cheap times, because I don't use the car every day.

Another consideration is how far away is your nearest SuperCharger? Mine is 3 miles away, so even if I hit a really odd scenario I can always hit the SuperCharger for a 10 minute charge.

The assumption is always that you must have an L2 charger, and that is simply not accurate for everyone. Think about your driving habits and whether you actually need to do this change.

 

[Sophias_dad]

Forgot to mention that it looks like you have a 20 amp circuit going to the garage already, and that means for a 5-20 UMC adapter($35) you can get 7 mi/hr of charge. (You or the electrician might have to change an outlet, because it permitted to put a 15 amp outlet on a 20 amp circuit)

 

[Kevin Tate]

I have a panel that's 50+ years-old, but I already have a 240V line into the garage with 8-gauge wire from the panel, so my electrician only charged for the new 40-amp switch in the panel, a small junction box to house the connection at the outlet and the costs associated with running an additional 40 feet of wire (and conduit) to the other side of my garage so that the Wall Connector would be closer to the charge port. Total price: $840. (And I live in CA.)

 

[bo3bdar]

I have a panel that's 50+ years-old, but I already have a 240V line into the garage with 8-gauge wire from the panel, so my electrician only charged for the new 40-amp switch in the panel, a small junction box to house the connection at the outlet and the costs associated with running an additional 40 feet of wire (and conduit) to the other side of my garage so that the Wall Connector would be closer to the charge port. Total price: $840. (And I live in CA.)

Nice. To be honest, I'm not sure I'd even do that, even if I could more easily do it. I've found the 120V charging to be perfectly OK for me, has never been a problem. Initially I was concerned, but figured I'd try it out first and see. Also slow charging batteries is typically better for them long term. The only real drawback is that 120V charging is not particularly efficient and wastes more energy than I'd like.

My electrical panel is a Pacific Electric- yes, that one. If I touch anything, I'm going to have to replace the entire thing. I can't use 240V circuits because of that, except for my stove which is on only for short durations and actively monitored. (The 240V breakers are the ones that fail and melt.) I've monitored my 12A circuit for charging the 3 and it doesn't even get warm at the breaker. And also the Tesla charger is a smart charger and will back off if it senses anything off. Have not added solar for the same reason, but I might have to just bite the bullet and do the whole thing.


One thing I ran across recently from a friend who has installed solar and has multiple Tesla's charging- he recommends upsizing any wire by one gauge, because the materials cost is not that large, and over time the lower I^2R losses of larger wire will easily pay for itself on a circuit like charging a car. You don't have to just follow the building code here, it's OK to upsize the wiring.

 

[Rocky_H]

Also slow charging batteries is typically better for them long term.

That is not at all relevant to any discussions about home charging, because ALL circuits for at home charging are extremely slow charging from the car/battery's perspective. You are talking about a system that can charge at power levels over 200kW, and this distinction of L1 or L2 at home is something like 1 or 10 kW. It's all very slow charging.