VTU (Voltage Tracking Unit) is a generation digital input module that provides voltage tracking in single phase or three phase systems. Digital input module has network analyzer specification that provides 4 channel voltage and 3 channel current input on device. In addition to network analyzer and voltage tracking, VTU provides to monitoring of energy parameters of single phase or three phase information that connects.Logical 1 and 0 informations can be set with VTU Configuration Software which voltage range will work. At the same time, power parameter may also be observed which is calculated as real time.