I have two Square D QO main panels split from a 320A service. They make a plug-in whole house surge protector for these panels.
Question: Would a QO plug-in surge protector placed in either panel protect the whole house, including circuits in the other panel?
The panels are right next to each other, and the service is split in a gutter right next to them. The phases and neutral are joined together at the split, less than two feet of cable away. The neutrals and ground are all bonded in the panels and via metal pipes and ground straps between the three boxes.
Secondary question: Right now the loads are spread randomly between the panels. I may one day rearrange all the loads in the two panels so that one of them can be a critical-loads panel. If I do that, the surge protector should be in that panel, I believe. And then, during an outage, the other panel will remain connected to the (dead) utility and have no surge protection. Is that the way to go? Is there any sense in putting a surge protector in each panel?