2 x 100A Panels, 1 Solar Inverter, 1 Sense Possible?

How can I make this work? Are there are Y’s for clamps that can take 2 sets of clamps and put it into 1 input on the sense to aggregate the signals? or do I need 2 senses (and therefore 2 accounts and a pain in the butt).

  • Solar
  • Tesla Powerwall 2/Gateway
  • 1 x 100A Panel for heating systems
  • 1 x 100A Panel for rest of house

Any creative solutions that can still give me the specific device data ? PW tells me total load of both panels but not device specific.

Are the two panels fed from two meters outside your house? If so, then you might be stuck with two Senses. If there’s a single meter, then there should be a single line coming into your house at some point before it is split into the two panels, and the Sense CTs should go there.

Similarly, does the solar feed into the Powerwall which then feeds into one of the panels? If so, the solar CTs go where the Powerwall feeds into the panel, and you see solar production as solar + Powerwall production (although Powerwall charging from the grid may not be accurately accounted for over time; I don’t know how well Sense tracks negative solar production). If solar and the Powerwall come into two separate breakers on your panel (or worse, one in each panel), you might be stuck if you can’t get the wires from both close enough together to put one clamp around both.

Can you describe or draw a rough outline of how the system is wired together?

I have a 2x200A install and I simple put my CTs on the single pair of mains that enter my utility meter.

@kevin1 I can’t clamp on the Grid mains because all that will tell me is how much power I am sourcing from mains, not what my total load is. My house can get sourced from Solar, PW, and Grid potentially all concurrently and as such, leads have to go on the house load side, not on any of the sources (except the solar ones go on the solar source to measure its production).

Up until this week, I only had 1 panel so it was fine. Further (to your point, @qrnef) I was not accounting for power being used to top up Powerwall because my leads weren’t in the gateway, only on the panel but I was ok with that as I was running Powerwall in backup mode really so it was just occasional top-up.

Now I have two panels and what I really need is 3 sets of CTs for one Sense (at least that makes sense - no pun). However, since there is no such beast, it appears as if I need 2 sense units unless there is some kind of Y connect to allow 2 sets of clamps into one input on the source but I suspect that is not possible and it is more complicated.

You have a PowerWall so that’s going to throw everything off, since Sense can only watch two pairs of CTs. For me, it works because Sense solar mode figures out my configuration during setup and adds my solar production to the net usage seen at the mains, to get total house usage. One question and one thought:

  • I thought PowerWall systems came with a complex set of CTs that allowed you to see real-time energy flow in the AP. If so, your other option might be to just focus on house load and ignore Solar since that is already metered in the Tesla App.

  • If you are willing to do that, you could just use the CTs on both 100A branches into the house, using the split service mode.
    Install Guide : Sense with 400A Split Service - Sense.com

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Now I understand your setup. Makes perfect sense. (ha! again!)

Your idea is an interesting thought for sure. I had quickly browsed the site about the split service mode/flex or whatever it is called. I do get all the solar production through the powerwall app as well and can download that data so from a total house setup perspective, I can see the net values. It doesn’t do some of the great things that the sense does like apply rates and give you the dollar values. I would hate to lose out on seeing the solar production not on my sense along with load.

However, the sense gives me the device intelligence that I really did want so if that solar port can be configured as a separate service that will also recognize the heating devices on panel 1, well that may in fact be a good compromise. Ultimately, I am in for some sort of challenge because even having 2 devices doesn’t solve the issue since you cannot have them under one account aggregating the data into one cohesive stream so I will be forced to consider some compromise.

Appreciate all the advice/assistance from you (and others).

Cheers

I have a similar setup and opted to install the CTs on the mains and where the PV comes in to the panel. I think this would work in your case as well, as the powerwall would just be seen like any other load. When you have excess PV and the powerwall is charging, your home’s power usage would reflect that. At night when the powerwall is discharging, the amount you draw through the mains will be lower than it would be otherwise.

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