The disclosed inventions relate generally to electrical boxes that may be installed to a ceiling, and more particularly to electrical box ancillary devices, such as brackets, plates and struts, that permit the carrying of heavy ceiling appliances such as ceiling fans and lighting fixtures. Disclosed herein are structural plates and other devices for attachment of ceiling fans and heavy lighting fixtures to structural members, such as trusses and joists, against the load of these fixtures. Also disclosed herein, explicitly or implicitly are methods of using and installing these plates and or brackets, devices and boxes. Detailed information on various example embodiments of the inventions is provided in the Detailed Description below.