A protection relay device, comprising: a plurality of merging units (2, 3) configured to collect information indicating a system electricity amount from an electric power system; and an intelligent electric device configured to protect said electric power system based on the information from said plurality of merging units (2, 3), characterised in that said plurality of merging units (2, 3) include: a first merging unit configured to receive first analog data indicating the system electricity amount from a first transformer, and to convert said first analog data into first digital data and output said first digital data to said intelligent electric device in synchronization with a synchronization signal supplied from outside; and a second merging unit configured to receive second digital data generated from second analog data indicating the system electricity amount from a second transformer, and to output said second digital data to said intelligent electric device, said second merging unit is configured to receive said synchronization signal, generate a request signal for requesting analog/digital conversion, and output said request signal to said second transformer, said second transformer is configured to convert the second analog data into the second digital data and output the second digital data to said second merging unit in synchronization with said request signal from said second merging unit, the protection relay device further comprising a correcting unit for configured to compensate for a phase difference in timing of analog/digital conversion between said first merging unit and said second transformer to thereby match the phase of the first digital data with the phase of the second digital data. a plurality of merging units (2, 3) configured to collect information indicating a system electricity amount from an electric power system; and an intelligent electric device configured to protect said electric power system based on the information from said plurality of merging units (2, 3), characterised in that said plurality of merging units (2, 3) include: a first merging unit configured to receive first analog data indicating the system electricity amount from a first transformer, and to convert said first analog data into first digital data and output said first digital data to said intelligent electric device in synchronization with a synchronization signal supplied from outside; and a second merging unit configured to receive second digital data generated from second analog data indicating the system electricity amount from a second transformer, and to output said second digital data to said intelligent electric device, said second merging unit is configured to receive said synchronization signal, generate a request signal for requesting analog/digital conversion, and output said request signal to said second transformer, said second transformer is configured to convert the second analog data into the second digital data and output the second digital data to said second merging unit in synchronization with said request signal from said second merging unit, the protection relay device further comprising a correcting unit for configured to compensate for a phase difference in timing of analog/digital conversion between said first merging unit and said second transformer to thereby match the phase of the first digital data with the phase of the second digital data. a first merging unit configured to receive first analog data indicating the system electricity amount from a first transformer, and to convert said first analog data into first digital data and output said first digital data to said intelligent electric device in synchronization with a synchronization signal supplied from outside; and a second merging unit configured to receive second digital data generated from second analog data indicating the system electricity amount from a second transformer, and to output said second digital data to said intelligent electric device, said second merging unit is configured to receive said synchronization signal, generate a request signal for requesting analog/digital conversion, and output said request signal to said second transformer, said second transformer is configured to convert the second analog data into the second digital data and output the second digital data to said second merging unit in synchronization with said request signal from said second merging unit, the protection relay device further comprising a correcting unit for configured to compensate for a phase difference in timing of analog/digital conversion between said first merging unit and said second transformer to thereby match the phase of the first digital data with the phase of the second digital data.