A power connector (100) is adapted for connecting with a power input port of an electrical device and includes an insulative housing (1), first and second terminals (2, 3) received in the housing for power transmission, a third terminal (4) received in the housing for signal transmission and a resistor (50) having certain resistance detectable by the electrical device electrically connecting with the second and third terminals. The first and second terminals respectively served as a positive pole and a negative pole of the power connector.