I’m in the midst of a renovation project, and I have a concern that the electrician has not wired a subpanel box inside the house correctly. The electrician has installed three panel boxes: 1.) the main box on the exterior of the house, 2.) a large sub-panel box (that feeds from the main box), and 3.) and a small sub-panel box (that feeds from the larger sub-panel box). The issue that I see is that I think the neutral and the ground are bonded in the large sub-panel box (picture below). My understanding of installation that conforms to code is for the neutral and the ground to only be bonded at the main panel box. Sub-panel boxes should have separated neutral and grounds.
Is there any situtation where a subpanel should have a neutral and ground bonded together?
I want to be sure I’m informed before I talk to the electrician about this.
Thanks for the advice!