the only time I would expect the EMS to find a frequency out of range is when connected to an open frame 3600rpm generator that is running at the incorrect rpm. (3600 rpm= 60hz).
Frequency of the normal "line" coming in is very tightly controlled, seldom will you see even a 1Hz error and the total error in cycles over 24hrs is in the handful. for the grid to work everyone in the grid (3 in the country, east, west, and texas) must be exactly at the same frequency and exactly in phase.
so, If you were connected to campground power and the grid, I suspect the EMS has a fault. BTW on my PD EMS unit that is installed in the trailer I can bypass it with the switch on the "dongle" unit. Nice when using a generator with an unbonded neutral.
