Bonding Question: 2 load centers under 1 power source and Impact of MTS

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Palestine, Texas
First post but I've not been able to definitively sort this one out... so I'd really appreciate feedback from any electricians who've encountered this before.

Utility power feeds my house via a 200A breaker panel that is bonded. I have a circuit from the main panel that feeds a 200A panel in my shop that is set up as a sub-panel.

I am installing a solar system that will supply my shop 100% of the time and it will be the only source of power for the shop. The circuit in my main panel feeding the shop will be removed. I will reverse the shop panel since it is no longer a sub-panel and it will need to be bonded.

Separately, I will also install a manual transfer switch (Non-Fused; 2 Pole; Double Throw) (GE TC10324R) after the utility meter that will allow me to direct either (a) Utility Power; or (b) Solar Power from my inverter to the main house panel.

The attached diagram shows what the system will look like after the solar install is complete. The shop will always get power from the solar inverter. Most of the time the house will get power from the utility but during power outages, the house will get power from the inverter.

So please confirm…

  1. Both of these panels are now the first means of disconnect to their respective buildings and therefore need to be bonded, correct?
  2. Does the MTS qualify as the first means of disconnect (and need to be bonded) and therefore my house main panel now is a sub-panel and should not be bonded? (Praying this isn't the case - ha!) I suspect not since it is non-fused...


MTS Diagram.png
Hey, wait a minute.

This is awkward, but...

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