From the remote manual:
http://www.magnum-dimensions.com/sites/default/files/manuals/owners/64-0030-Rev-C-ME-ARC_CD_Web.pdf5.2.2 Charger Mode
Turning the charger on: The charge mode is automatically activated and
begins when acceptable
AC power (utility/generator) is connected to the input of the inverter. When in charge mode,
the display may show: Charging, Bulk Charging, Absorb Charging, Float Charging, Full Charge,
Silent, Charger Standby, Force Float, Equalizing, Load Support VDC, and Load Support AAC
Acceptable power seems to be 60 Hz.