The units of primary supply to interpret
cefcTotalAvailableCurrent and cefcTotalDrawnCurrent
as power.
For example, one 1000-watt power supply could
deliver 100 amperes at 10 volts DC. So the value
of cefcPowerUnits would be 'at 10 volts DC'.
cefcPowerUnits is for display purposes only.