Service Entrance defined as the Trailer distribution panel.

Ref: http://www.biogasassociation.ca/bioExp/images/uploads/documents/NOP-032=Policy_on_Power_Quality.pdf

Normal Operating Voltage Range = 110 to 125 Volts,

Extreme Conditions Voltage Range = 106 to 109 Volts and 126 to 127 Volts