Just ordered a custom US bundle

Hello IoTaWatt community. My order is on its way so I just wanted to run a few things through the people here. I have a 200A split phase grid supply with a 100A split phase solar and 2 Tesla powerwalls. Here is what I have ordered:

200A CT (2) - Mains 240V
100A CT (2) - Solar 240V
50A CT (1) - Well pump 240V
50A CT (1) - Cooking range 240V
50A CT (1) - AC 240 V
50A CT (1) - AC 240 V
50A CT (1) - Furnace
50A CT (1) - Refrigerator + Dishwasher
50A CT (1) - Kitchen area
50A CT (1) - Master Bedroom
50A CT (1) - Family room
50A CT (1) - Garage

Not all circuits are going to be measured. I will post pictures and further information as I make progress in the installation. Comments welcome. Thanks to @overeasy for making this tool available and also for creating this community. I know its not as easy as it looks.

I’m seeing more and more Powerwall (and other battery systems) integrated into home energy systems. None that I have seen are posting any scheme to measure battery charge/discharge. It seems to me that if I had such a hybrid system I would be more interested in getting a firm understanding of that dynamic. This system, with possibly 20kW or more of solar and 26kW of battery represents a lot of energy flow. At a minimum, knowing the energy used by the loads, the energy flow in and out of the battery system, the solar generation and the energy flow in and out of the grid, it should be possible to develop an accurate measure of the battery system efficiency over time (the longer the time the less significant state-of-charge).

As I understand it there are several different ways to connect and use Powerwall, so there are probably different approaches to measurement. At the end of the day I would think measuring (and integrating) the battery charge/discharge would be very useful data.

My system is 12.3KW with 26KWh of energy storage capacity. I am already capturing the metrics you mentioned using Influxdb/Telegraph/Grafana. This includes solar generation, battery ingress/egress, grid ingress/egress and home usage.

I am more than willing to help out if you think there is room for further integration using IoTaWatt.

I see all of the ingredients for those metrics are being captured by IoTaWatt except for battery ingress/egress. So you are getting solar output, grid import/export and home usage from Powerwall? I was not aware that they provided all of those metrics. I’ll be curious to see how metrics like home usage compare to IoTaWatt’s measurements.

The Powerwall gateway API is documented here: https://github.com/vloschiavo/powerwall2.

I am using this to capture the metrics: https://github.com/mihailescu2m/powerwall_monitor

I can provide a comparison of grid and home usage once I have my IoTaWatt installed and functioning.

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Did a quick power on and completed basic setup. Unit connected to wifi successfully and I am able to view the dashboard.

The voltage shown by the unit is 124.6 and my multi meter shows 125.2. Granted its not a Fluke unit but is this an acceptable deviation? The VT unit is JW-95001-NA.

That’s 0.5%. That’s probably an acceptable deviation for your multimeter.

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Finished installation today. Here are some pictures. The enclosure is made by Husky from the orange home center. I used split flex tubing as conduit since I needed something flexible due to short run from panel to the enclosure. It was very difficult to fit the mains & solar CTs. I somehow managed it bit the panel cover does not sit flush now since one of the 200A CTs are sticking out a bit.

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What is the part number for the enclosure. It looks interesting, but I didn’t see anything like that online.

Looks like it might be this one:

Not really an electrical enclosure.

Yes, that is the correct one. It is not an electric enclosure but not sure if one is needed for low voltage circuits.

@overeasy I am planning to combine the 2 “Solar” CTs into one input using a headphone splitter. The Solar CTs are 2x AcuCT-H063-100. I have 2 Powerwall+ batteries and each one is rated for max 40A current and connected to a double pole 50A breaker. I believe these CTs would satisfy the requirement to combine them as per the docs. Correct?

Two individual CTs can also be combined with a common headphone splitter and fed into a single IotaWatt input. When combining this way, both CTs must be the same model with an individual capacity sufficient to measure the combined capacity of the two circuit breakers.

Here is a picture of the Powerwall breakers:

That should work. Can I see a picture of that box with the cover removed?

Here it is. The cables on the top go to the main load center and can be seen entering from the left in the picture I posted earlier.

Should be fine. You also have enough slack to run each pair through one CT in opposite directions.

Thanks. I am already measuring them in the main panel using 2 100A CTs (one on red and one on black feeders) as I mentioned before. What I will now do is feed these into just 1 input on IotaWatt using a headphone splitter.