Confused about net metering setup

[galvan]

Hi all,

Apologies in advance for a newbie question that has probably been asked before. I am an IT geek and not an electrician, so any wiring/terms past the GEM or Dashbox is a mystery to me. I recently had solar installed, and the electrician wired the GEM and Dashbox for me.

GEM: COM version 5.23, ENG version 1.49
Dash: 4.2.4b17a
GEM is connected via serial to the Dashbox

Channel 32 is connected to the mains via SPT-200
All other channels are Micro-40
Solar is connected to channels 25, 27.
On the electrical panel, the solar is tied to breakers 25, 27. Picture attached.

Given a snapshot of current readings in Live Data on the GEM:
25: "1229 w"
27: "-1229 w"
32: "1028 w"

1. Do I set 32, 25, and 27 in GEM setup to Net metering?
2. Do I have to change the Disable polarity toggle for any of these channels?
3. Likewise, in the Dashbox settings, I assume I also set Net metering for the desired channels (if it's indeed 32, 25, 27). Should the direction be set to "Reversed" for any?

Thanks kindly for helping out!

[galvan]

Edit - I believe I have figured this out. I removed the Net Metering toggle from the Main channel, and changed the polarity of one of the solar channels. Both the Channel 25 and Channel 27 Get now show a negative value, but are "in the green" on the gauges. Adding those up matches what my solar company's monitoring system is showing.

One oddity is that my furnace is not reading any values. Other 240v devices (dryer, stove, and an electric baseboard heater) are all reading OK, and also have Micro 40 CTs on both of their joined breakers. Looking at the GEM they are also wired the same as the others.

Any ideas on that? Other than this remaining issue I am loving this so far, it's going to turn me into a power miser!

Thank you!

[ben]

Edit - I believe I have figured this out. I removed the Net Metering toggle from the Main channel, and changed the polarity of one of the solar channels. Both the Channel 25 and Channel 27 Get now show a negative value, but are "in the green" on the gauges. Adding those up matches what my solar company's monitoring system is showing.

One oddity is that my furnace is not reading any values. Other 240v devices (dryer, stove, and an electric baseboard heater) are all reading OK, and also have Micro 40 CTs on both of their joined breakers. Looking at the GEM they are also wired the same as the others.

Any ideas on that? Other than this remaining issue I am loving this so far, it's going to turn me into a power miser!

Thank you!

Sorry, didn't notice this post until now.

Net should be set on the Main Panel if you're sending power back to the power company via your main breaker. If your solar has a separate meter then you don't need it.

If you remove one set of CT leads from the channel with the furnace does the value go up? If so reverse one set of leads as they're cancelling from eachother due to being out of phase.

[galvan]

Thanks Ben, I probably should have put this in one of the support forums.

I just tried removing the leads from one channel (20) of the furnace. Activated furnace, no reading. Replaced those leads and removed the others (channel 22) and still coming in at 0 watts.

[ben]

Thanks Ben, I probably should have put this in one of the support forums.

I just tried removing the leads from one channel (20) of the furnace. Activated furnace, no reading. Replaced those leads and removed the others (channel 22) and still coming in at 0 watts.

Are the CT settings set correctly under the GEM Setup Webpage Chan CT page?

Are these Micro-40s?

Really strange to get 0. Do you happen to own a multimeter?

[galvan]

Yes they are Micro-40s. In the GEM they are configured as Type=211, Range=4, Model=M-40. (all except the ones for the Main are set this way)

I do have a multimeter...

[Teken]

Yes they are Micro-40s. In the GEM they are configured as Type=211, Range=4, Model=M-40. (all except the ones for the Main are set this way)

I do have a multimeter...

I would suggest you take the same CT once it’s confirmed wired correctly. Place it on another working (monitored) circuit and see if any values are captured and displayed. If there is you’ll need to identify the error and fault.

If there is no reading it could be a bad CT which is extremely rare and unlikely. If you have a spare CT place it on the same GEM furnace channel and see if power is being captured as doing so confirms the port, settings, are fine.

[ben]

Yes they are Micro-40s. In the GEM they are configured as Type=211, Range=4, Model=M-40. (all except the ones for the Main are set this way)

I do have a multimeter...

I would suggest you take the same CT once it’s confirmed wired correctly. Place it on another working (monitored) circuit and see if any values are captured and displayed. If there is you’ll need to identify the error and fault.

If there is no reading it could be a bad CT which is extremely rare and unlikely. If you have a spare CT place it on the same GEM furnace channel and see if power is being captured as doing so confirms the port, settings, are fine.

This may be easier, also try a known working CT on the GEM channel to make sure it isn't GEM-side.

[galvan]

Ok, I figured out the problem. LOSER ERROR on my part. Can I blame the lack of labeling on the original panel? This was on a completely different (normal 15A single breaker, labeled "basement plug") as my furnace is oil fired and I now see it peaks at around 300 watts, I'm guessing that's all the circulator pumps and igniter use.

The other one I was troubleshooting the lack of readings is wired to a separate electric baseboard that I never use. Sorry!

At least the GEM/Dashbox is finally helping me map out the wiring in my old house. I may have some follow up questions on my original topic of net metering once I dive in a bit more. Thanks all!

[galvan]

Now that I'm done wasting people's time with hunting down breakers, I am back to deciphering my net metering as there is something I'm not understanding. I'll attach several images with setup and data. As my solar generation increases, so does the reading on the channel that I've set to Main (which if I recall is my total consumption).

This data is being generated from MQTT. Legend:
Channel 32 = Main panel
Home Usage = sum of all channels except 32 and 25/27 (solar breakers per my first post)
Solar Gen = sum of 25 and 27
Channel 64 = Channel 32 Gen
Net Usage = (Home Usage - Solar Gen)

The Home Usage and 32 (Main) are equal until my solar production starts. I would have thought that Total Consumption would represent power from the grid and go down as my solar production increases? But instead both 32 (Main) and Total Consumption are increasing as my solar production increases.

Attached is a last 12 hour graph, a last 3 hour graph, and various setup screens.

thanks again.