Can the CTs face opposite directions?

Reading thru the install manual I see it doesn’t matter which direction the CTs are mounted. I remember reading somewhere here that if the readings are backward one can contact Tech Support and they will fix it in the software. I am in a situation where I am trying to mount them around a bus bar making them 100% vertical.

This makes them difficult to put the front cover back on as one of them opens up. I wonder if I could mount that one upside down so this isn’t an issue. What will happen?

It’s my understanding that Sense has updated the way it runs the calibration and they have created an auto-correct for negative input current (i.e. a flipped CT clamp).

A quick look through help.sense.com and blog.sense.com and past Community topics reveals some holes in the official recommendations in your situation. @RyanAtSense, can you clarify and update?

This is my interpretation:

  1. Ideally the clamps should be installed in the same direction to the current.

  2. If #1 is not the case, in the 48hr-ish calibration process Sense will confirm through current readings that a CT is flipped and calibrate accordingly (i.e. take that as a positive vs. negative reading)

  3. If during #2 a user manually flips a CT the calibration process could get confused and “locked in” to possible erroneous settings. In this case a restart may fix things.

  4. Restarting the Sense monitor will confirm current direction on startup … meaning if the clamps are alternated in direction a re-calibration will occur.

So in your situation my guess is you can flip the CT and restart and everything should re-calibrate auto magically. If not, wait a while and then contact Support.

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That was what I was hoping would be the case. Since I cannot hook it up until after my final inspection for the solar, and I am curious, what happens when one is flipped? It will go negative and the other stay positive, so they will fight and you will see next to no current? I suppose it will be really easy to see on the Sense Monitor display in settings.

Yes, the best place to look is in the Settings > Signals because it breaks out the two input legs and you can see the wattage for each leg.

It’s not that you see no current if one is flipped but you may see zero or negative total watts. The orientations are calibrated relatively. You could have BOTH with negative current for example.

The current readings are taken individually on each CT and the wattage is the sum of each leg (i.e. current X voltage per leg).

Correct!

Correct! (as long as the CTs are fully closed)

(mostly) Correct! The best thing to do is to let the signal check process do its thing and not intervene. But if you decide to intervene (again, please don’t), a data reset should be performed immediately after.

(mostly) correct! It won’t trigger an automatic re-calibration process, i.e., what we call Signal Check, but it will send an automatic alert to the Support team to look into.

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Thanks for the input, I did the Data Reset and it did put the Sense into a Signal Check again, so it is going to hopefully detect everything correctly now that I have it permanently mounted in it’s new home in the solar combiner box. I was having issues putting the cover back on the main panel with everything stuffed in there. Perfect fit in the combiner box, and I ran an extension to the main box for the main CTs.

I did the trick with flipping one of the CTs so that they both fit around the buss bars the same (mirror image) way, with the clamp lever on the back. Before it was getting pressed by the cover when I put it on and opening enough to give grief on readings.

I am taking the long Labor Day weekend away so the Signal Check will not be interrupted by my curiosity. The new solar system seems to be mostly working, though a few panels are not responding. I’ll troubleshoot once I have some baseline data from the Sense Monitor and the Enphase Envoy over the next 4 days or so.

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So OF COURSE when we got to the cabin the Sense went down. I even checked to see if the solar circuit (that the Sense taps for power) was down and it appeared to be as well.

Showed the wife and she said she knew I was going to OBSESS about this if we didn’t go home, so after brunch we buttoned up the cabin and turned around. When we were driving home I checked to see that it was still down. The solar looked like it had gathered more power, but was not showing anything recent, so still looked down, but perhaps intermittent. Sense had no updates since noonish. I even had an email letting me know that the Sense was down.

We got home hours later and after unpacking the car I went looking at which breaker was tripped, but none were. So I looked at the Sense app again and it had just come up 9 minutes earlier. WHAT?

So I opened the viewer on my laptop to be sure it wasn’t the iPhone, and it showed the same thing. No data earlier than a 1/4 hour before. It was like it was trying to update and couldn’t get a connection. When we got back from the dog park however, the Sense app NOW showed data from 12:45pm or so all the way up to current. WHAT???

Where was that data hiding? Why did it pretend to NOT be recording the data? I think I just don’t know the solar well enough to judge when it’s not reporting, but I have had the Sense since May.

Overnight I saw the reconnecting dot pattern again every time I looked. This morning it was showing that so I went to the side of the house and turned the antenna 90° hoping that would make a change. When it connected it claimed there was no power being used but lots of solar was starting to come in. The web app showed the power was negative and the Signals section of Settings showed the power coming in was negative too. A message on the timeline said something like “Oops! Something is wrong, attempting to recover. Don’t make a change to the Sense setup whatever you do”

It then individually toggled the power for each leg from negative to positive and seems to have settled on it being positive, but it’s VERY high. Like it is adding the solar power to what it sees on the mains. As the solar has increased this AM so has the indicated power being used. Like instead of 1000 watts it’s showing 6000. It went back to saying “Sense is checking your Installation” so hopefully it will go back to normal soon.

Currently showing:

IMG_8864 fullsizeoutput_5319fullsizeoutput_5325

I kinda lost track of all the ins-and-outs here but what I know is that if Sense loses signal (wifi) but not power then it will record “offline” for up to 6 hours.

It certainly sounds like you are having connectivity issues. If Sense backfills data that it didn’t previously show, that sort of confirms that as it is able to record data even if it doesn’t have a network connection. The fact that you sometimes get the dots and other times not, then that sort of confirms it to me. If you haven’t gotten a “Sense is Offline” e-mail from Sense, that also shows that the Sense is connecting just enough to the Mother Ship to say “here I am” to prevent that message going out. I’m also thinking that maybe due to the intermittent network connectivity, the signals check process may keep getting interrupted which is why it seems weird.
If you touch base with Support on tuesday, they may be able to tell you if the Sense is having issues connecting to wifi / the internet.

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Looks like it’s done until Tuesday. The message
“Uh, Oh. Sense has detected an installation problem that we are unable to fix automatically. Sense Support has been contacted and is taking a look for you.”
came up and when I tried to reset data again it wouldn’t let me.

If the issue with it dropping the connection was WiFi related it is new since I moved it two feet from the Main Breaker Panel to the new Solar Combiner box. Still has the antenna coming out of the bottom of the new box. But it was the only device I had that was showing status as anything but Excellent, it said Good. I moved an Airport Express within 15’ of it and the Sense moved its connection and now shows as Excellent on that Airport, so WiFi is no longer a potential issue.

EDIT: Finally let me reset the monitor, not sure why it didn’t earlier, so ignore previous comment

That dot pattern or “connect the dot” as I call it, happens if you ha e too many instances of Sense open.
If I have iPhone, iPad and android all open simultaneously, this pattern emerges.

Yay! I woke up this morning and it finally is working with the CTs facing opposite directions. Seems to be showing my solar and my grid perfectly.

I thought the lack of connection was my issue with how long the Signal Check took, but with the better WiFi connection it took from Sunday to today (Wednesday). I usually don’t see the dot pattern, perhaps it was the new location, perhaps I was having internet issues that day.

Looking forward to all those device being re-discovered

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