Lynn,
The FDOT "inspectors" typically inspect soil conditions, layering of material, etc., they are not inspectors as we know them under 468, like you say. My catch was that the entity installing the traffic light services was a subcontractor. They need the power company to "energize" and they were told that only the county had the power to release power. So it trickled down from there.
A good place to begin is with FDOT specifications for traffic control devices. Their page for this can be found here:
Traffic Systems — Product Specification...Signal Devices)The specifications for the electrical service, complete with references back to NEC, can be found here:
SECTION A639
ELECTRICAL POWER SERVICE ASSEMBLYThe design standards page can be found here:
Design StandardsAnd the diagram for the electrical service can be found here:
Electrical Service DiagramThe FDOT website is LOADED with information and it could literally take days to go through it all. I reference it frequently when I am involved with ADA related work. It is very helpful, and their goal seems to be to have all the information online.
To answer your question though, there would be an exception if they were exempt. I can find no such exemption in F.S. 553, or any other statute, the FBC, nor the NEC. Seems like if there was an exemption, we would be able to locate it. If someone knows of an exemption from permitting requirements or NEC please post back and let us know.