A connection union for a fluid line (11) containing a fluid duct (14) has at least one signal conductor (16a and 16b) in the wall (15) of the fluid line (11) for the transmission of electrical and/or optical signal. The connection union a fluid line socket (23) and a holding device (25) for the fluid line (11) and at least one signal contact (31a; 31b) for the production of a connection with the at least one signal conductor (16a and 16b). The at least one signal contact (31a; 31b) is able to be slid in the insertion direction (28) of the fluid line (11; 68 through 71) and is provided with spring means (37) so that during a longitudinal movement of the fluid line (11) mounted on the connection union (10) the at least one signal contact (31a; 31b) remains connected with the at least one signal conductor (16a and 16b). Moreover the invention contemplates a suitable fluid line (11) and a fluid power means belonging to it.