The invention relates to a large manipulator for concrete pumps with a arranged on a frame, rotatable about a vertical axis of rotation mast block, with a composite of at least two mast arms articulated mast carrying a concrete delivery line, and at least one hydraulic drive unit for pivoting at least one of the mast arms a horizontal axis of rotation comprising a hydraulic cylinder (154) and a piston (156) movably mounted in the hydraulic cylinder (154) and having a piston rod (158) connected thereto. In the hydraulic cylinder (154), a piston-side working volume (160) which can be acted upon with hydraulic fluid and a rod-side working volume (162) which can be acted upon by hydraulic fluid are formed. According to the invention, the large manipulator contains a hydraulic circuit arrangement (164) for driving the at least one hydraulic drive unit, which in a first switching state has a first working connection (168) for the supply or discharge of the hydraulic fluid through a first fluid channel (170) with the rod-side working volume (162 ) and a second working port (172) for the supply or discharge of the hydraulic fluid through a second fluid channel (174) with the piston side working volume (160) and the in a different from the first switching state second switching state, the first working port (168) of the first Fluid channel (170) separates while connecting the first fluid channel (170) with the second fluid channel (174) for supplying hydraulic fluid from the rod-side working volume (162) in piston-side working volume (160).
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