DIY Tesla Wall Connector with Load Management

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This weekend I installed a Tesla Wall Connector and a Neurio W2 Power Meter and configured them for dynamic load management. Dynamic load management means that the EV charger will dial down the charge rate from 48A whenever the Power Meter detects that total load is close to the maximum load of the electrical service to the house. For houses like ours with 100A (or less) electrical connections that’s very convenient because we can charge our EV quickly without tripping the main breaker in the few brief instances where we’re both charging our car and running all the other electrical loads in the house.

You obviously should never do what I did and should always hire a licensed electrician and Tesla installer.

Parts

  • Tesla Wall Connector. I bought this retail from the online Tesla store.
  • “Tesla” Neurio W2 Power Meter. These can be had from eBay.
  • Cable to connect Wall Connector and power meter. The part number is 1133339-00-A and I also bought one from eBay. It’s just a low-voltage, two-conductor cable with a 6-wire connector on one end. I’m sure it would be very easy to improvise but I couldn’t be bothered to figure exactly what connector it uses. The cable does have a fancy QR-code tag on it, but scanning it is not part of the setup.
  • Breaker, electrical wire (eg. 6/2 or similar THHN if you’re using conduit) and other stuff for wiring the wall connector.

Installation

  1. Install the Neurio Power Meter. There’s a good how-to video on YouTube. It’s unclear to me if the WiFi connection is required when paired with a Tesla Wall Connector but I added the antenna for good measure. The main challenge for me at this stage was finding a spot in our already busy electrical panel and fiddling with cables for CT clamps and so on.
  2. Install the Wall Connector. Ours is installed right below our electrical panel with the power wire coming from behind.
  3. Connect power meter and wall connector. I chose to drill a separate hole in the wall connector back-plate for the power meter cable comms cable instead of trying to run it with the power wires, mostly because the comms cable isn’t very long and that way I didn’t have to mess with trying to extend it. The Wall Connector has an elegant design where the power wires all attach to the back plate and then the face plate just slots on. Unfortunately the comms-port is not part of that scheme and is on the face-plate assembly. So you have to connect the power meter comms wires while balancing the face-plate and then secure the whole thing to the back-plate.
  4. Initialize the Wall Connector. You can do this using the Tesla One app. The app is supposedly only for Tesla employees and 3rd party contractors but you can log in using a normal retail Tesla user account just fine. When you scan the QR code that’s on the Neurio power meter it starts showing up as part of the install and you can configure the CT clamps. Check if you need to “flip” them to ensure the meter registers power flowing in the right direction (“import” vs. “export”). At this stage you can also configure the max load where you want EV charging to start dialing down. Note that I didn’t configure the Neurio separately, it was all through the Tesla app.
Tesla Wall Connector back-plate with power and comms cables
Tesla One app screenshot, configuring when charging should be limited
Tesla One app screenshot, configuring the CT clamps on the Neurio W2. Note that the clamps are not yet “flipped”.

Summary

We haven’t taken delivery of our Tesla car yet so I haven’t actually tested the dynamic load management. But I wanted to document this process since it does seem to work and the power meter registers with the Tesla app and site install and appears to be recognized. I’ll update this post when I’ve confirmed the setup works and throttles charging when we’re using all of our other appliances.

Comments

Harsh Singh on

Hi – thank you for putting this up. Was very useful as I was able to show to an electrician who configured the meter with the wall connector. Question for use the Neurio meter is flashing red and green. Is that how yours as is after the install. Thanks.

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Olyts on

Mine is flashing (alternate) Red and Blue, seems to work fine (once I flipped the CT’s). I tested the setup and yes the TWC is adjusting dynamically according to the max limit you have set.

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Fabrizio on

Hello, thank you for the guide.
I would like to ask you if there is the possibility of connecting via wifi only instead cable as already happens for the Backup Gateway.

Kind Regards

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Olyts on

Thanks for this write up! Quick question, on the WC rs485 connector, do connect the comm cable red with red and black to white?

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friism on

I think they changed the design for this, mine had a green double-connector that said +/-. I connected the red wire to positive, if I recall.

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Arash Ardeshirpoor on

Hello ,
Would
You please explain more about the part which you said we need to connect the power meter to the wall connector with a low voltage line. Where exactly we have to connect ?

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friism on

It depends on the model/generation of wall connector, but it should have a green or red/white terminal block for rs485. You can see someone hooking it up in this video.

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John on

I notice on eBay there are 3 different part numbers in listings for the Neurio W2 (1112484-04-A; 1112484-99-A; 1112484-06-A). What did you use, and are there any part numbers specifically not compatible with the Gen 3 wall connector? I’d rather pay $100 on eBay than $250 on Amazon. Thanks!

Reply

Olyts on

Just finished installing my first Neurio. Went smoothly. I can confirm the red wire goes to the red terminal (for those who, like me, have a rs485 Red/White connector). After some unsucessful testing of the unit (I turned on many power hungry devices in my home to get the amp up!), the meter was displaying the right amount of amps, but the Wall connector was not adjusting, staying at 48 amps. I took a second look at the configuration, and once I selected « flip » on both ct in the wall connector config, all was good and the amp level was adjusting to keep everything at the max I provided. (80% of your max pannel load)

I don’t really understand the export/import thing (I guess this has more to do with powerwall), but the « flip » option did the trick for me. And before you asked, yes the clamps are on the right orientation in the Pannel.

Always test afterward, is the key here.

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