At an outdoor event consisting large tents (plywood floors, metal tubular frame, poly tenting), air-conditioning, lighting and public address system is powered by a trailer-mounted 3-phase (208 v) generator. The generator rental place drove a ground rod and connected its ground connector there.
Event organizers ran audio & video system of the generator. TV cables, and telecom cables were run from a business building and used with the audio & video system. (All except air-conditioning are single-phase 120v.)
Ground loop issues became apparent with difference between the 2 grounds (the utility and the generator). Switched audio & video power to the utility power to help solve the issue.
But now the issue of grounding comes up as we add wiring and switch boxes for the lighting (powered by the generator) that will be near the audio & video control station (powered by the utility via the building).
To be safe, should these 2 grounds be tied together? Where?
If this turns out to be beyond our abilities to solve we will call in a electrician, but if it is as simple as tying the grounds together there isn't a need, is there.
All constructive suggestions are appreciated.
Thanks much,