Panel physics

[MartinW]

Just had or 20.1 kW Tesla/Solaredge system activated. Quick question about panel physics. I have noticed that in the morning the system registers little "bumps" of energy generation - but with concurrent "bumps" in my USE graph (using the solarxity website NOW function). Is low energy generation an active process that requires a bump in energy used?

Appreciate your insights!

M.

 

[rfmurphy81]

I just had my system activated, too. PTO was yesterday. Today was the first full day of generation and, even though no one was home, I noticed consumption power was jumping around in the Tesla app for the few times I checked, somewhat in relation to the generation power even though no one was home and the house would have been at it's baseline.

I put a call into their Tech Support line to see if there was an issue with the Power Blaster they installed (CTs were reversed or something) or maybe a configuration in their gateway to adjust but, since their systems still show me in "Utility Inspection", I need to wait for the activation to properly go through on their side which apparently will take a few days.

I also have a Neurio in my main panel and have been seeing the consumption and generation data even more closely aligned but am working with their support team to hopefully figure it out. My Neurio data seems a bit more extreme than the Tesla app had been showing with the real time power data.

Once I can get into the PowerGuide on MySolarCity.com, I can confirm where a problem may exist. SCE seems to take a few days to show their usage data so, by then hopefully Tesla will finally show my system as active and I'll be able to compare what I captured today against Tesla and Neurio soon enough.

 

[strangely]

Just had or 20.1 kW Tesla/Solaredge system activated. Quick question about panel physics. I have noticed that in the morning the system registers little "bumps" of energy generation - but with concurrent "bumps" in my USE graph (using the solarxity website NOW function). Is low energy generation an active process that requires a bump in energy used?

Appreciate your insights!

M.

Can you post a screen grab? Sounds like maybe they don't have the CTs configured correctly. When mine was first installed there was some weird issues like this and they had to do a bit of rewiring and reconfiguration.

Does the consumption match the same values as the energy produced?

 

[MartinW]

Thanks for your thoughts. Sorry about the image quality, but hopefully, you'll be able to zoom in.

M.

 

[rfmurphy81]

To follow up on my earlier post, I ended up having someone from Tesla come out and fix the CTs. The installers had put it on only one half of the mains after it was broken out into two phases by the mater (meaning it was only measuring Phase A rather than also Phase B). They moved the CTs to connect prior to the meter so it can measure 100% rather than the "half". I'm also noticing that the consumption data now seems to more closely align with my Neurio and what the utility meter shows as the net usage. I also saw that the PowerGuide reflects appropriate data based on the consumption and generation matching the net via the utility meter.

Here's my PowerGuide just now:

This shows me turning on my heater at 1:12 then, 90 seconds later, the blower going.

It seems like the many ups and downs are expected because their Power Blaster device is constantly reading the measurements.

 

[Shygar]

Is Tesla not using Neurio's anymore? That's what is in my backup gateway

 

[rfmurphy81]

Is Tesla not using Neurio's anymore? That's what is in my backup gateway

Nope. They are using a device called PowerBlaster which has CTs around the mains which communicates with the SolarCity gateway. I'm unsure whether the inverter communicates with the PowerBlaster or the gateway directly. My install was 1/29/19.

 

[cwied]

I think the difference is whether it's a Powerall install or a solar-only install. I think the PowerBlaster is what SolarCity used to use when they were independent.

 

[strangely]

Thanks for your thoughts. Sorry about the image quality, but hopefully, you'll be able to zoom in.
View attachment 375551
M.

My guess is that they may be summing the solar when it should be subtracted. I don't have Tesla solar, but the way my solar is set up on my personal monitor is that any generation is normally shown as a negative (this is the way I set it up).

If this is the issue, the generation CT/CTs can either be turned around, or if you have access to the wires from the CT, then swap them. Either of things should reverse the polarity and allow it to subtract instead, and you should see a corresponding dip in your consumption, which should be correct and what you would normally expect.

 

[cwied]

The sign of the current measurement can also easily be switched using the setup wizard. This would avoid having to open up any panels if you're not comfortable doing so.

 

[MartinW]

Great points. Basic question: What does CT/CTs mean?
Martin

 

[cwied]

CT is Current Transformer, the sensor used to measure current in the wires in your panel. In a Powerwall installation, they plug in to a Neurio device inside the Gateway box which uses the measured current to calculate the power numbers that are displayed in the app. See: Current transformer - Wikipedia

 

[Shygar]

I think the difference is whether it's a Powerall install or a solar-only install. I think the PowerBlaster is what SolarCity used to use when they were independent.

Oh ok, that makes sense. I didn't realize OP didn't have a powerwall. I have two houses, one with solar and powerwall (with Neurio), and one with just solar, both from Tesla. My solar only house didn't get this PowerBlaster installed (installed Jan 2018). I installed my own Neurio over there because the standard SolarCity box is terrible.