The utility model relates to an isolated plant for being directed at electric energy meter that possesses CT secondary circuit state monitor function carries out global function and detects, include: current transformer group, secondary circuit state analog control module, constant current source module, constant voltage source module, liter flow module, loop current voltage testing and a plurality of epitope functional module. Wherein current transformer organizes and the loop state of secondary circuit state analog control module collaborative work in order to simulate different secondary circuit, constant current source module, constant voltage source module and liter class module organize for current transformer and secondary circuit state analog control module provides accurate adjustable electrical parameter, the real -time current value and the real - time voltage value of each measuring point among the loop current voltage testing detection simulation secondary circuit, the epitope functional module will be surveyed the table and connected on the secondary circuit of current transformer group and the simulation of secondary circuit state analog control module to calculate measuring voltage value and the measuring current value and the error of real - time voltage value with real -time current value of being surveyed each measuring point of table measuring.