A controller for a generator set is disclosed. The controller may have a memory module having stored therein calibration factors associated with an offset error, a scale error, and a time delay error, and a processor module in communication with the memory module. The processor module may be configured to monitor at least one parameter of electric power directed from the generator set to a load, detect connection of the generator set to the load, and determine adjustments to the calibration factors after connection of the generator set to the load based on a comparison of the at least one parameter monitored by the processor module and measured at the load.