The first picture with the arrows pointing up shows where the main current sensors are. They are connected to the 200 amp bus bars ( Behind the protective cover ) They are fed from the power pole
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The second picture shows the positioning of the solar sensor CT clamps. I have 2 inverters. The larger inverter ( 40 Amps ) has a black and red wire. One wire goes through one of the clamps, the other wire goes through the other clamp Those are shown by the arrows pointing DOWN. The second inverter has 2 black wires. One wire is also fed one through one clamp the other through the other clamp… Those are shown by the arrows pointing UP.
Steve, So I have this set up as you’ve described, in my sense is subtracting the difference between both inverters and stead of adding them together. Any suggestions on how to fix this? Also are you using net metering with your utility company, or are you completely off grid? I’m also showing negative numbers and usage as well.
Sounds like PG&E didn’t charge for the visit. Who did you call for the service request ? I have a couple friends who are interested in Sense, but their homes have the same breaker box setup as mine, where the CTs have to go onto the pre-meter incoming mains inside the meter box.
KEN
I have net metering. Currently in the sense monitor display under settings mine shows mains 1244,661w solar 4360 and 4124 and my solar production in the power meter is the sum of the 2 solar number and consumption the sum of the 2 mains numbers. My meter shows me feeding power back to the grid around 6-7KW.
Have you looked at the figures in the settings?
I am really not an expert on this , but since it worked before as I think you said, I would guess it is something basic. Have you retried the solar install part? I think you may be able to disable solar then reenable it and go through the setup part. That would be the first thing I would try as it doesn’t involve anything major. Are you sure the legs of both inverters are going through the CT’s in the same direction and the arrows are aligned right?
I didn’t have to get PGE involved as the bus bars are accessible behind the cover up top in picture 1. The meter sits to the left in another panel. This entrance panel was designed specifically for solar service tying in along with sub panel feeds.
The guy who ran my inverter wires into my box from the out side disconnect set this up. One inverter feed enters my box from the bottom, and one from the top. The yellow arrows are my two breakers the solar feed into from the inverters. I have one red and one black wire per inverter. The green arrow show my black wires Solar CT. The blue Arrow showes my red wires Solar CT. I wonder if the position of the CT (blue arrow) is causing this discrepancy. Or how one red leaves the CT and runs up the right side of the box, while the other runs across the left left side and up.
My 2c - if you are seeing a pure subtraction (i.e. your solar reading is the difference between production from the two), you likely either have:
Both CTs reversed for one solar array with respect to the other one (looks like you actually have correct in the photo)
The black and the red connections to the breaker legs / phases are reversed between the two solar arrays. That’s possible given your picture. Inverters sync with the the waveform coming into the box from the grid, so this wouldn’t cause any issues for power production, but would mean the current flow between the two inverter would be 180 degrees out of phase, causing current subtraction in correctly aligned CTs.
Sense has a way for correcting reversed CTs vs. phase polarity, for a single solar feed, but your issue can’t be corrected since your physical topology is blending the two current flows.
To: @ken4 From looking at your setup, it appears from your photo that you have a Square D “QO” 42-space breaker panel installed. Look at this website (go to the sub-section that shows the 11 separate pictures, select the one without the cover and breakers installed) and you will see that the backplane (without the breakers installed) has the ‘stab plate’ with a connection point on every other position. I think you have your phases mixed up. You need to probably move your wiring so both connections are linked to the same phase. There is a ‘right’ side phase and a ‘left’ side phase (or what is called split phase). This might be something that SENSE support can correct with their software, but I think the real problem lies with the physical location of the wiring on the breakers.
Also I would recommend that the black wire connected to the upper right-side breaker be terminated with less copper showing. Too much insulation was stripped from the wire before it was connected (terminated). It will work as it is, but it does pose a minor safety hazard for anyone working on the panel.
One last recommendation: Try to position the CT clamps so they are 90-degree perpendicular to the service wires and centered on the wiring. Use some foam inserts to align them. Tape the CT clamps closed. You will get a slightly better reading from SENSE that matches the Power company’s monthly reading.
Thank you for the advice, I looked at the pictures and saw what you were talking about, and it makes a lot of sense. I also noticed the amount of insulation that was stripped back off of that one wire, and that was on my list of things to do when I climbed back in the box. The install job is not as clean as I would like it and planned on tweaking som things. I was considering re-running my red wires to try and position a second CT for the solar (Blue arrow) to be symmetrical with my other CT running the black wires (green arrow)
If you are safety minded, then you might consider purchasing a set of these rubber barriers that slip around the service connections at your Square D main breaker. They are easy to install.
UL67 service entrance barriers (yellow plastic safety barriers) from Schneider-Electric.
Unfortunately I didn’t record the phone number that eventually worked. I do recall having to try a few different support numbers. I think it was the service connect/disconnect crew because there was potential need to interrupt service to my meter. With insulating equipment and careful work by the PG&E guy, he didn’t need to interrupt my service.
The only thing missing here are custom observation windows into the panel so we can see the CT clamps. But I won’t fault you for their absence … probably can’t even do it anyway and stick the NEC.
wow I’m jealous of your utility company. I’ve got the same exact panel, and they refuse to let me put on anything around the main lines coming in because it’s “behind the meter”. I escalated it with the supervisor and was told to modify my CT sensors to fit below or get a new panel. so ridiculous
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