A transformer having coupler

A coupler mounted transformer is provided to improve integration of hardware by including a coupler for processing a low voltage power line communication signal and a high voltage power line communication signal. A sensor part(100) includes a power sensor and a sensor for monitoring a transformer integrity. The power sensor obtains power state information required in a power quality and a load management. The sensor for monitoring a transformer integrity obtains transformer state information. An analog/digital converter(300) is connected to the sensor part through an interface(200), and converts an analog signal obtained from the sensor part into a digital signal. A digital signal processing device(400) processes and analyzes a digital signal. A memory(500) stores the processed information. A micro controller(600) manages the information processed by the digital signal processing device. A low voltage and a high voltage power line communication modules(700, 701) transmit the power state information and the transformer state information through a low voltage power line or a high voltage power line. A low voltage and a high voltage power line communication couplers(800, 801) send a communication signal to a distribution line.