are transferred into the register 13 and the contents in the counter 11 is transferred into the register 12 in response to the pulse which appears at the point c during the time interval t 5 for reading the digit at the 10 3 position the contents in the register 14 are transferred into the register 15 the contents in the register 13 into the register 14 the contents in the register 12 into the register 13 and the contents in the counter 11 into the register 12 thus the reading or indication of the meter m is stored in the registers 12 15 in the centralized data terminal ii in summary according to the first embodiment of the present invention a line for transmitting the power to each remote terminal equipment i may be eliminated that is the data may be transferred from each remote terminal equipment through only two transmission lines l 1 and l 2 to the centralized data terminal ii so that the installation costs may be considerably reduced and the data collection system may be simplified referring to fig3 5 as with the first embodiment described above the centralized data terminal ii is connected through the two transmission lines l 1 and l 2 to the remote terminal equipment i the remote terminal equipment i includes a control circuit generally indicated by the reference numeral 30 in response to the clock pulses transmitted from the centralized data terminal ii the control circuit 30 reads the data or indication of the meter m and controls the switching transistor tr 0 so as to transfer the read data to the centralized data terminal ii in the centralized data terminal ii a clock pulse generator not.