Power Quality - Notable Power Quality Issues

Hi all -
My name is Chris and I’m new to the forum. I see a lot of activity here which is great and wanted to pose a question to those in-the-know.

Back in May of last year I had a solar system and battery installed at my house. Since installation, my solar inverter has started shutting down randomly with ever-increasing frequency. Installer says I’m having overvoltage issues and said I need to call the power company. Power company hasn’t been very active about looking into it and I’m trying to get a little more information before I follow up with either of them or an independent electrician. This is where Sense comes in. It’s been able to give me a lot of data on my voltages and looking at the patterns, it sort of looks like a floating neutral to me. However, I am not getting a floating neutral warning in the app. So, two questions:

  1. I’d like to be able to identify if this issue existed prior to the solar installation (which also involved moving my meter and service) or whether it is a new issue. Does Sense keep any voltage data from more than 30 days prior (particularly back prior to May of 2021).
  2. I’ve uploaded my voltage graph screenshot to see if anyone has any ideas
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Welcome to the community.

Could you tell us more about your solar setup? Hybrid, or battery backup?

Within the labs section found in the app at the bottom of trends… labs - power quality. Are you get any alerts there? Does your inverter have a fault detection or a self diagnoses section.
I am not aware of a way to export the more data from the power quality tab (web browser) other than what is included there which is normally ~30 days.

The reason you can’t post a screen shot/ photo is due to where you are brand new to the forum.

Could you tell us what your power quality from labs data is showing?

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I’ve upgraded your permissions so you should be able to post images now.

I updated the original post with my voltage graphs. My solar setup is a Tesla Solar roof with two PowerWall batteries. I have a Tesla gateway that manages the flow of current between the house, grid, batteries and solar array. I have a Delta M inverter for DC-AC conversion.

I have alerts in my Sense app for Power Quality and AC Energy Comparison. No alerts for motors or floating neutrals.

I’ve also attached some exports from Sense and custom graphs here.
sense_data.xlsx (217.0 KB)

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The (NEC) National Electric Code for 2020 now requires two grounds rods for residential units spaced greater than 6-feet apart. Most homes do not have this since the code was only recently adapted. You might try installing a second ground rod. Homes located where the soil is very dry, may not be getting a good ground. (I recently installed a second ground rod at my home. We live where the soil is always wet/moist.) The cost is minimal for the materials. Lowes or Home Depot will have the supplies you need. Just be careful where you pound the second ground rod. You don’t want to destroy underground electrical or plumbing.

Here is an article I submitted several years ago. Try cleaning your current outside grounding connection. Corrosion may be creating an issue.

If neither of those ideas help, then you will need an electrician to inspect your breaker panel ground connections or the power company will need to check their grounding at their transformer.

Or the issue may be at the Solar/battery installation. Can you submit some pictures of your panel, setup, wiring connections, etc. to the forum?

Or possibly an animal has tunneled under your transformer and piled up dirt that is creating issues on your power leads like this transformer in our neighborhood. The exposed aluminum metal connecting bars on the right side should not be contacting any ground/dirt.

Good Luck.

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Power company finally came out and it looks like they had an issue on their end (I assume at the transformer). My voltages are still on the high side (~124-126) but they are now balanced across the legs at least so my inverter isn’t tripping.

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