400amp service and Neurio

[daveh85]

The install of my system isn’t ever showing power getting fed back into the grid, instead the Solar and Grid are added together to make the Home calculation.

I have a 400 amp service that is split into 2x200 amp panels. Only one of these is backed up with the Gateway 2. A Neurio is used to calculate the total load across both. This is where I think the problem exists.

One pair of CTs are used on the main feeder for the non-backed up panel, and another is on the backed up legs of the load center. These CTs are paired for the same phase. I suspect this is where the issue is... shouldn’t the CTs be on both feeders (one pair for the non-backed up panel, and the other on the feeder in the gateway)?

if anyone has a similar setup would they mind sharing the install

 

[miimura]

The install of my system isn’t ever showing power getting fed back into the grid, instead the Solar and Grid are added together to make the Home calculation.

I have a 400 amp service that is split into 2x200 amp panels. Only one of these is backed up with the Gateway 2. A Neurio is used to calculate the total load across both. This is where I think the problem exists.

One pair of CTs are used on the main feeder for the non-backed up panel, and another is on the backed up legs of the load center. These CTs are paired for the same phase. I suspect this is where the issue is... shouldn’t the CTs be on both feeders (one pair for the non-backed up panel, and the other on the feeder in the gateway)?

if anyone has a similar setup would they mind sharing the install

There is no way to correctly measure the energy if there is one pair of CTs with each CT measuring the same phase of different legs of the supply. Any imbalance or consumption on the other phase will not be counted correctly. I believe the correct way to do the installation is to place a remote Neurio in the main panel with a pair of CTs, one CT around each phase of the non-backup panel feed line. It would then have to be configured to add this grid consumption to the grid CTs in the Gateway 2. Alternatively, they could place the Neurio CTs so that they measure ALL grid flow before the split to the two panels and configure the system to ignore the grid CTs inside the Gateway 2.

 

[daveh85]

Interesting. Just so I wrap my head around this, use a splitter for each phase with one CT going to phase A of the non-backed up and the other CT going to phase A of the Gateway. Same for phase B?

I thought you couldn’t use the Grid CTs in the Gateway if you were measuring Grid with Neurio. I need to log back in and confirm.

 

[miimura]

Interesting. Just so I wrap my head around this, use a splitter for each phase with one CT going to phase A of the non-backed up and the other CT going to phase A of the Gateway. Same for phase B?

I thought you couldn’t use the Grid CTs in the Gateway if you were measuring Grid with Neurio. I need to log back in and confirm.

I don't think you have to use splitters. A Neurio has 4 inputs. You can use each channel as part of a pair measuring opposite phases or you can use them singly to measure 120V loads or double the value for pure 240V loads. So, purely with the Neurio, you could have one pair measuring the Backup panel and one pair measuring the non-Backup panel. The Gateway would still have to add everything together to represent the whole grid consumption.

Whether or not you can use the Neurio and the Grid CTs in the Gateway depends on how the software in the Gateway works. I'm not sure about that.

 

[shred86]

@daveh85 did you ever get this resolved? My Neurio was installed using a splitter to measure two electrical panels (200A & 100A), so four CT clamps total. I'm getting some weird readings at times in the Tesla app and when I log into the inverter directly.