A fuel cell stack is disclosed, so as to prevent the corrosion of the power output terminal plate due to coolant and the occurrence of electric short circuits through the coolant, and to improve the flexibility of selection of the coolant. A reference position on a floor surface on which the moving pedestal moves and a reference angle of the moving pedestal are both set. Methods and systems according to the present invention achieve key routing requirements while presenting solutions that can be readily scaled to large network environments. When the actuating piece is pressed to the extent that the securing piece is escaped from the recesses, the backrest can be adjusted and its inclination can be changed.