Solar Cancelling out Consumption

This seems to be a regular issue with solar as there are other topics about this in different forms. I want to bring attention to it because honestly, it is a waste of everyone’s time to have to keep bringing this up.

After turning on my solar system I noticed quite often that my solar production is reliable, but my energy conumption gets cancelled out (shows 0w) when solar is > consumption. This is a pretty silly error. Is this something the customers can fix in the the device settings?

I believe, like in the post you linked to, you are experiencing a fairy common setup issue. I have set up my solar on several Sense devices and 1 time out of 4, had a similar experience - the rest worked as expected. can fix the setup remotely.

I mean, neither sense or any of it’s customers should have to waste time on this if it’s clearly a repeat issue.

The point is that neither Sense or any of its customers should have to contact them for this issue that is an obvious thing. If this is a repeated issue, and there is another way to go about setting up solar without running into this, they should do some preventative maintenance.

I suspect it is harder to get right than you think. Sense has every incentive to make setup work perfectly for every install. The challenge, as I understand it, is that there are maybe 20 different variants of solar installs, polarity combinations (when folks don’t quite get them all oriented correctly), how the solar is backfed into the grid, microinverters vs large inverters, etc. Sense has to try to ascertain from measurements alone, but sometimes gets it wrong.

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Isn’t just a matter of reversing the direction of the solar CT’s ?
I am under the impression that Sense only reverses the “polarity” of the solar sensors in their setup.

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Maybe if it was installed correctly then you wouldn’t have to waste time on it. It’s an incorrect install issue that they might be able to remedy through software.

If you wire your dryer incorrectly yourself and you burn down the house are you going to say “My electrical utility should have figured I would do this. As a customer I shouldn’t have to waste time on insurance claims and rehab”.

The install is exactly as it’s instructed, and was verified by two electricians. How many people have you done this too? I can post at least 5 YT videos that claimed “incorrect installation” when the installation was in fact very correct. Don’t get all aggro about it when you can search your own forums and see that this is not an uncommon issue.

Edit: That is very much an apples and oranges comparison by the way.

Nah. Its a software issue. As long as the solar production is less than the consumption, it shows up perfectly correct.

I am in no way associated with Sense. These aren’t “my forums”.

I might have a slight bit of agro due to slightly toxic language you use in all your posts, but that’s beside the point.

I experienced the same issue with a generator, which is identical in that both provide electricity to the panel. I installed the CTs and monitor myself so therefore I have first hand experience with the same issue. I will admit, the installation instructions for MY configuration was wrong and following the instructions led to the issue you’re experiencing. To rectify the issue I installed the main CTs between the ATS and the load and the flex CTs between the ATS and the gen. Once I did that then all was good.

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Have you tried to switch solar CT clamp 1&2 , so change active phase?
It must be something simple

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There’s a 1 and 2? I don’t remember seeing anything labeled. I can give it a try but it shouldn’t make a difference really. P=IE

That’s for an actually intelligible response. This makes some sense. All that being said, my panel and exact configuration are identical to “Serviceside Tap > Acceptable configuration: A”.

Ok, so in my case I attempted to do exactly what is shown in the diagram for solar config A and I experienced the same issue. In order to resolve it I had to move the main CTs down below the juncture point. In my case it’s an ATS, in your case it’s a solar tap.

The logic behind this is that when you are connected to the utility side before the tap with the CTs then you are only monitoring draw from the utility. Thus, if your solar is higher than your demand you will register nothing. If it’s below the tap you will always see the draw regardless of utility or solar. Furthermore I would argue that you’re not going to get good device discovery if you’re only monitoring the load from the utility. I “believe” that the solar CTs aren’t in charge of monitoring load, they just monitor the power going into the panel. In other words, your load is your load, no matter where you get the power from.

Here’s what I had to do in order to fix the issue you’re experiencing. Please note, I am not a Sense employee. I have no idea if this will work on your system like it did on mine. I make no warranties that this will work and I recommend that you contact an electrician and don’t do the work on your own. This drawing is my rendition of what worked for me. It’s not an official Sense diagram.

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To be frank, when installing this I thought it was peculiar that it was okay for the CTs to be above the IPC lugs\taps rather than below, so I just assumed they would do the math to show consumption. Obviously the sum of the CT’s minus production = consumption, right? /shrug. I’ll move my CT’s and see what happens.

Hey folks. New install here and I’m having very similar issues ! My setup has solar backfed through breakers. I had the two solar CTs connected there (with the sun sign on both pointing towards breaker), and then I had my main CTs connected to the two main live phases (checked that V diff between them is 240 so I don’t accidentally monitor neutral), and made sure the “home” sign is pointing away from panel (the direction of utility company), as some old version of the manual appears to say. Since my production > consumption in day time, as I expected, the solar was positive and the two mains were negative, and the main display would show it as 0 which I thought was a software correction. I checked that turning on a device makes the main CT less negative which made sense to me.

8 hours later, I get the (hmmm…) message showing 50% completion. At this instant, the software decides randomly to flip the phase of one main CT (so now one reads positive and one negative), and this seems to last indefinitely. I waited 2 days then did a data reset and started over again and got same issue. I now turned one AC on and saw a spike of power up so I thought ok this is a good sign. Then I started the other identical AC units and nothing seemed to change on the graphs. The numbers don’t make sense at all to me now.

I want a ground truth: when everything is installed correctly and everything is working fine, what am I expected to see in the main display ? When solar is being produced I should see solar wattage as a positive value on both phases right ? And What about the main side ? Should it show positive when consuming ? Or when being back fed ? What is the sign convention here ? My guess is that it should show positive when consumption > generation, and negative (and equal to generation) when generation > consumption. What is the correct state ?

I think logically you should expect to see actual production and actual consumption without any intervening maths (outside of P=IE).

@addohm @kevin1’s point is the most accurate depiction of what’s happening here. Additionally, the presence of (usually backfed) solar can make it more difficult for the signal check process to correctly determine the monitor’s configuration. That would of course get corrected through support channels, typically without involving user contact. For a large majority of solar install issues after set-up, Support can issue a fix pretty quickly.

Obviously, it is preferred if solar installations can be completed without contacting Support. The benefits of this don’t need to be spelled out. We have some things we’re actively pursuing for solar enhancements, but would not expect to see a short-term solution here.

Why not remove installation configuration A? That seems like a good start. That, or note on it that A is best without a solar install. Anything is better than what exists right now I think.

@addohm after you moved the CTs did it work as expected?