Abstract: A safety system connecting a pressure medium source, user, and a pressure reservoir (accumulator) has a pressure port, a supply container port, a reservoir port, a three-way valve and a pressure relief valve. The pressure relief valve is attached to the pressure port and to the three-way valve. The valve member of the three-way valve in a first position connects the pressure port with the reservoir port. In a second position, the valve member connects the reservoir port with the supply container port. To avoid the disadvantages of a three-way valve with negative overlap, an arrester check or anti-return valve is inserted between the pressure port and the reservoir port closing toward the reservoir port. The three-way valve has a positive overlap.