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M3 and a Bolt, TWC x 2, one 30-amp circuit: Will it work?

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I have a Tesla Model 3. Been using a NEMA 14-30 and the Mobile Connector for three years. Good experience. (Did only 30 amp since we were re-using conduit already in the ground to a detached garage and that was the max wire size we could fit in there.)

Wife is adding a Bolt EUV to the mix. Detached garage, full panel, only 100 amps to the house, tearing up new patio or driveway, etc. etc.: Getting another 220V to the garage is hard.

Question1: Could I replace the NEMA 14-30/Mobile Connector and permanently install two Tesla Wall Connectors on the same 30-amp circuit and have them automatically not go above 24amps?
Question2: Could the second Tesla Wall Connector charge a Chevy bolt? (thinking via some $150 Tesla-->J-1772 adapter)

I've never had a Wall Connector, so I don't know much about them (do they have an app to control them, etc.)
 
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Get a NeoCharge Smart Splitter

 
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That is super cool, thanks!... but the problem I have is that I'm only on a NEMA 14-30 outlet. NeoCharge has that model... but the Chevy Bolt mobile charging thing doesn't seem to have a dongle for 14-30 and only comes with a 14-50...
Also be aware that the Neocharge costs more than a wall connector, and provides no real 'sharing' at all. It provides an automatic switch, a hard cutoff to one while the other is running. That might be fine for you, or not.

That said the adapter from a wall connector to a j1772a connector is not cheap... around $159. I believe I have read on these forums somewhere that sharing works fine with two HPWCs even when one has been converted to j1772a by an adapter like this.
 
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provides no real 'sharing' at all. It provides an automatic switch, a hard cutoff to one while the other is running.
Nope


How are you able to charge two cars simultaneously using one 240V outlet?​


In order to charge two EVs simultaneously, you'll need any EV charger OR any EV that support setting a current limit. For example, on a 50 Amp circuit you safely pull up to 40 Amps of continuous power. This means you can set the current limit on your car/charger(s) to charge both cars at 20 Amps (or any combination summing to 40A i.e. 30A + 10A), and your Smart Splitter will intelligently balance power between the two devices. As an added safety feature, if the total power ever exceeds 40 Amps, your Smart Splitter will sense this and shut off your secondary charger or device.
 
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He doesn't need a wall connector.

He already has a mobile charger for the Tesla Model 3

Chevy Bolt also comes with a mobile charger.
Problem: The Chevy Bolt mobile charger only has a 14-50 adapter. That's my main crux. With my Tesla, I was able to choose from a variety of connectors and charging amperages. I could only fit a 30-amp wire in the conduit to the detached garage, so I went with that.

Chevy doesn't seem to have dongles for 14-30 (and maybe it doesn't switch to anything but 50-amp, even if I could make one) for their mobile charger. That's my main problem.

I thought the two x TWC would be an elegant/clean sharing of a single 30-amp circuit. The NeoCharge is a good second option, but only if I could use a 30-amp power source for the Bolt. As cool as the NeoCharge is, I would like to see if I could get the auto-sharing (admittedly, dual charging would be down to only 12A per car. But hey, better than 110V over 5A (I bet that wouldn't even maintain in Cleveland weather.)
 
Problem: The Chevy Bolt mobile charger only has a 14-50 adapter. That's my main crux. With my Tesla, I was able to choose from a variety of connectors and charging amperages. I could only fit a 30-amp wire in the conduit to the detached garage, so I went with that.

Chevy doesn't seem to have dongles for 14-30 (and maybe it doesn't switch to anything but 50-amp, even if I could make one) for their mobile charger. That's my main problem.

I thought the two x TWC would be an elegant/clean sharing of a single 30-amp circuit. The NeoCharge is a good second option, but only if I could use a 30-amp power source for the Bolt. As cool as the NeoCharge is, I would like to see if I could get the auto-sharing (admittedly, dual charging would be down to only 12A per car. But hey, better than 110V over 5A (I bet that wouldn't even maintain in Cleveland weather.)
As I pointed out earlier, NeoCharge has the NEMA adapter for that

 
I think I'd keep it simple and either:

1) Try a TeslaTap so you can use your existing TMC with the Bolt (it's a Tesla_to_J1772), I hear they're very compatible vs. no-name brand.

2) Get a 3rd party charger, 40a, a 14-50_to_14-30 adapter and set the charger for 24a, then use your supplied J1772_to_Tesla adapter

The reason I suggested a 40a charger is that will future proof that purchase a bit more and costs very little more than a lower amp option. And, if you do wind up with a 50a circuit, the 40a charger can be shared between the two vehicles seamlessly (i.e., it will supply only the max requested by the vehicle up to 40a - we do this with a TM3 that supports 40a, and a Wrangler 4xe that supports 32a - just pop on the Tesla adapter, works perfect).
 
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Problem: The Chevy Bolt mobile charger only has a 14-50 adapter. That's my main crux. With my Tesla, I was able to choose from a variety of connectors and charging amperages. I could only fit a 30-amp wire in the conduit to the detached garage, so I went with that.

Chevy doesn't seem to have dongles for 14-30 (and maybe it doesn't switch to anything but 50-amp, even if I could make one) for their mobile charger. That's my main problem.

I thought the two x TWC would be an elegant/clean sharing of a single 30-amp circuit. The NeoCharge is a good second option, but only if I could use a 30-amp power source for the Bolt. As cool as the NeoCharge is, I would like to see if I could get the auto-sharing (admittedly, dual charging would be down to only 12A per car. But hey, better than 110V over 5A (I bet that wouldn't even maintain in Cleveland weather.)

Buy a separate 14-30 EVSE. Yes, it's an extra cost, but then you can keep the Bolt's EVSE in the car.

There's also long been a product called a DryerBuddy that people have used primarily to share with a dryer, but it has an added option to allow use with 2 EVSEs (and some dryers). More "industrial" and no app but it has a number of different options available, including splitting from the dryer socket to a remote outlet.
 
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As I pointed out earlier, NeoCharge has the NEMA adapter for that


The problem is that, as far as I can tell, the Bolt doesn't have configurable amperage. Using their mobile connector 14-50 will cause the Bolt to charge at 32A.

The simple (though additional cost) solution is to buy an EVSE with a 14-30 plug. I have a dumb Clipper Creek because I already had a 30A circuit available and I didn't expect smart charging. Actually there's a smart-charging trial but it required purchase of particular EVSEs with 14-50 plugs.
 
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As I pointed out earlier, NeoCharge has the NEMA adapter for that

But if I connect the Bolt 14-50 to the NeoCharge when the NeoCharge is plugged into a 30amp, will the Bolt charge attempt to draw 50amp?

If the NeoCharge is smart enough to allow only 30 (24) amps through the 14-50, does the Bolt Mobile charger accept the lower amperage? I’m dubious as Chevy doesn’t seem to make any other dongles other than 14-50.
 
But if I connect the Bolt 14-50 to the NeoCharge when the NeoCharge is plugged into a 30amp, will the Bolt charge attempt to draw 50amp?

If the NeoCharge is smart enough to allow only 30 (24) amps through the 14-50, does the Bolt Mobile charger accept the lower amperage? I’m dubious as Chevy doesn’t seem to make any other dongles other than 14-50.

According to Chevrolet, it'll try to draw 40 amps, the maximum(continuous) on a 50 amp circuit. The car has no way of seeing what your supply/adapter situation looks like. Unless you can tell the CAR to reduce the charge rate, the charger(really connector) included with the Bolt will blow your breaker or burn down your house.

Think of the neocharge as a simple light switch. It can send power to outlet A or outlet B. If A is drawing more than a tiny amount of current, B will be shutoff completely.

I believe this is another example of non-Tesla automakers playing catch-up. Sorry.

You might want to look into a dual-headed j1772a station. I know Grizzle-E makes one for around $900
 
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For your question 1, yes, you can by setting up both Tesla Wall Connectors to have load sharing enabled in the software.

Install each Wall connector on it’s own wiring and circuit breaker from a small sub panel. Make sure the wiring will support the full 30 Amp capacity. Each Wall Connector will be able to charge each car individually at 24 Amp continuous. Use a Teslatap to convert the Tesla plug to a J1772 for your Bolt. Just be aware that you will only get 12 Amp (2.8 kW) to each car when charging both at the same time. That will take a long time to get to full, but if you charge both every night, you won’t need to charge as much SOC to get back to 80%.
 
But if I connect the Bolt 14-50 to the NeoCharge when the NeoCharge is plugged into a 30amp, will the Bolt charge attempt to draw 50amp?

If the NeoCharge is smart enough to allow only 30 (24) amps through the 14-50, does the Bolt Mobile charger accept the lower amperage? I’m dubious as Chevy doesn’t seem to make any other dongles other than 14-50.
That, I do not know the answer to because it is vehicle specific.

Can you search the function the vehicle to see if there is a setting?
 
Question to consider: Do you really need 2 EVSEs? Maybe you do, but speaking as a two EV household, now that my wife and I both have long range EVs, we find that we don't really need two (or in our case a dual-headed) EVSE. We did when we had a slow charging (3.3kW) EV and a slow charging PHEV that both needed to be charged every night, but now that we both have long range EVs that do not need to be charged daily, it is easy enough for us to coordinate which nights we charge such that there is not contention (even though we technically can both plug in at the same time). And even though our current EVSE is 30A (versus the 24A that would be your limiting factor), our usage is not such that we even need the entire night to charge either vehicle even when it gets down to our low point that we plug in (which in the case of my Tesla is still 100 miles, which incidentally is more range than my original LEAF had when new and full!)

So I would give some consideration as to whether you can get by with a single 24A J1772 EVSE. Your needs may require more than that, but before you outlay money on multiple EVSEs and/or adapters, it's at least worth considering.
 
So I would give some consideration as to whether you can get by with a single 24A J1772 EVSE. Your needs may require more than that, but before you outlay money on multiple EVSEs and/or adapters, it's at least worth considering
Could probably also get by with a single tesla to j1772a adapter, since the UMC can already throttle either car to 24A.
 
According to Chevrolet, it'll try to draw 40 amps, the maximum(continuous) on a 50 amp circuit. The car has no way of seeing what your supply/adapter situation looks like. Unless you can tell the CAR to reduce the charge rate, the charger(really connector) included with the Bolt will blow your breaker or burn down your house.

Think of the neocharge as a simple light switch. It can send power to outlet A or outlet B. If A is drawing more than a tiny amount of current, B will be shutoff completely.

I believe this is another example of non-Tesla automakers playing catch-up. Sorry.

You might want to look into a dual-headed j1772a station. I know Grizzle-E makes one for around $900
I would not recommend Grizzl-E. I have their single plug charger and it runs way too warm for the amps it’s drawing. If I set the Tesla to charge at anything above 24a the temp on the Grizzl-E plug will get to 160 degrees or more. I have put a ticket in to their support and have yet to hear back over a week now. I’m about to the point of replacing the charger with a TWC.
 
I would not recommend Grizzl-E. I have their single plug charger and it runs way too warm for the amps it’s drawing. If I set the Tesla to charge at anything above 24a the temp on the Grizzl-E plug will get to 160 degrees or more. I have put a ticket in to their support and have yet to hear back over a week now. I’m about to the point of replacing the charger with a TWC.

Ours had been fine (~14 months old, Smart/40a/N6-50), and definitely does not get that warm (I checked with a pyrometer to compare the old outlet - see below), even with a long charger of adding like +60-70%, so that does sound like either a squirrely unit.

I think I've seen you post in some charging setup threads, so I think I recall you were down with the better brand receptacles - but FWIW, when I replaced our "discount brand" with a better one, the temps went down quite a bit too.

Bummer about your CS experience, I've heard such good things about that specifically, a couple of folks on another site, one got a quick replacement, the other was able to swap his smart for a standard, and get refunded the difference without a lot of hassle.
 
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