Electronic pipettor origin calibrating method and special device

The invention discloses an electronic pipettor origin calibrating method and a special device. In the method, a control unit controls a reciprocating unit to reciprocate in an internal cavity of a shell by a step drive unit, when the movement of the reciprocating unit is blocked, the step drive unit stalls out, the stallout of the step drive unit causes the current which is supplied to the step drive unit by the control unit to change, the detection and control unit traces the change of the current, thereby judging whether the reciprocating unit reaches the end of the internal cavity of the shell or the set termination, then restoration is carried out according to the preset origin position of the electronic pipettor, thus facilitating the reciprocating unit to move to the origin position.The invention has simple structure and process, convenient usage and beneficial effects of high precision and reduced product cost.