Apparatus for conveying thick matter, having: - at least one drive cylinder (10a, 10b) for receiving hydraulic liquid, at least one drive piston (11a, 11b) which is arranged in the drive cylinder (10a, 10b), at least one conveying cylinder (12a, 12b) for receiving thick matter, at least one conveying piston (13a, 13b) which is arranged in the conveying cylinder (12a, 12b), and at least one piston rod (14a, 14b) which is fastened to the drive piston (11a, 11b) for motion coupling to the conveying piston (13a, 13b); - wherein the drive cylinder (10a, 10b) has a rod-side passage (SDa, SDb) for the pressurization of a rod side (SKa, SKb) of the drive piston (11a, 11b) with hydraulic liquid and has a crown-side passage (BDa, BDb) for the pressurization of a crown side (BKa, BKb), which is averted from the rod side (SKa, SKb), of the drive piston (11a, 11b) with hydraulic liquid; - a drive pump which is designed to generate a drive volume flow, with a drive pressure (pA), of hydraulic liquid for the movement of the drive piston (11a, 11b); - at least one pump connection (30a, 30b) which is designed for the changeable connection of the drive pump to the rod-side passage (SDa, SDb) or to the crown-side passage (BDa, BDb) for the flow of hydraulic liquid; - a sensor device which is designed to independently detect whether the pump connection (30a, 30b) is connected to the rod-side passage (SDa, SDb) or to the crown-side passage (BDa, Bdb); and - a control unit which is designed to control the apparatus in a rod-side operating mode if a rod-side pump connection is detected and to control the apparatus in a crown-side operating mode if a crown-side pump connection is detected; - wherein the sensor device is designed to measure at least one characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2), which is dependent on the pump connection side, of the drive piston (11a, 11b), of the conveying piston, of the piston rod, of the hydraulic liquid and/or of the thick matter in detection operation of the drive pump and to detect the pump connection side based on the measured characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2); - characterized in that the sensor device is designed to, based on the drive volume flow and/or a drive pump pressure (pA), in particular the drive pressure (pA), determine at least one comparison variable, compare the comparison variable with the characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2) and/or with a variable based on the characteristic variable, and detect the pump connection side based on a comparison result. - at least one drive cylinder (10a, 10b) for receiving hydraulic liquid, at least one drive piston (11a, 11b) which is arranged in the drive cylinder (10a, 10b), at least one conveying cylinder (12a, 12b) for receiving thick matter, at least one conveying piston (13a, 13b) which is arranged in the conveying cylinder (12a, 12b), and at least one piston rod (14a, 14b) which is fastened to the drive piston (11a, 11b) for motion coupling to the conveying piston (13a, 13b); - wherein the drive cylinder (10a, 10b) has a rod-side passage (SDa, SDb) for the pressurization of a rod side (SKa, SKb) of the drive piston (11a, 11b) with hydraulic liquid and has a crown-side passage (BDa, BDb) for the pressurization of a crown side (BKa, BKb), which is averted from the rod side (SKa, SKb), of the drive piston (11a, 11b) with hydraulic liquid; - a drive pump which is designed to generate a drive volume flow, with a drive pressure (pA), of hydraulic liquid for the movement of the drive piston (11a, 11b); - at least one pump connection (30a, 30b) which is designed for the changeable connection of the drive pump to the rod-side passage (SDa, SDb) or to the crown-side passage (BDa, BDb) for the flow of hydraulic liquid; - a sensor device which is designed to independently detect whether the pump connection (30a, 30b) is connected to the rod-side passage (SDa, SDb) or to the crown-side passage (BDa, Bdb); and - a control unit which is designed to control the apparatus in a rod-side operating mode if a rod-side pump connection is detected and to control the apparatus in a crown-side operating mode if a crown-side pump connection is detected; - wherein the sensor device is designed to measure at least one characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2), which is dependent on the pump connection side, of the drive piston (11a, 11b), of the conveying piston, of the piston rod, of the hydraulic liquid and/or of the thick matter in detection operation of the drive pump and to detect the pump connection side based on the measured characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2); - characterized in that the sensor device is designed to, based on the drive volume flow and/or a drive pump pressure (pA), in particular the drive pressure (pA), determine at least one comparison variable, compare the comparison variable with the characteristic variable (P1a, P1b, P2a, P2b, Ta, Tb, PV, p1, p2) and/or with a variable based on the characteristic variable, and detect the pump connection side based on a comparison result.