An electrical connection device is provided which comprises: a first wire port comprising a first terminal and a second terminal; a second wire port comprising a third terminal and a fourth terminal; a switch assembly being electrically coupled between the first wire port and the second wire port, wherein the switch assembly comprises a first switch operable to couple the first terminal to the third terminal or the fourth terminal, a second switch operable to couple the second terminal to the third terminal and a third switch operable to couple the second terminal to the fourth terminal; a polarity detecting unit configured to detect a first polarity between the first terminal and the second terminal and a second polarity between the third terminal and the fourth terminal and generate a first polarity signal and a second polarity signal respectively; a main processing unit configured to receive the first polarity signal and the second polarity signal to control the switch assembly.