Mass connection system for a test system, comprising: a receiving frame; and at least one carrier frame (30, 30', 30", 30#, 30 ∗); wherein the receiving frame has several recesses, which in each case completely penetrate the receiving frame in the thickness direction and are in each case open towards an insertion edge of the receiving frame, wherein each recess defines two mutually parallel side walls (121, 122), which in each case enclose an angle of between 60° and 120° and preferably 90° with the insertion edge, wherein each carrier frame (30, 30', 30", 30#, 30 ∗) has two mutually parallel side walls (131, 132), which are designed to come into positive mechanical engagement with the parallel side walls (121, 122) of each recess of the receiving frame, and wherein at least one carrier frame (30, 30', 30", 30#, 30 ∗) further has an opening for holding at least one contact carrier (40, 40', 40#), wherein all recesses in the receiving frame have the same inner contour, and wherein all carrier frames (30, 30', 30', 30#, 30 ∗) have the same outer contour, wherein the outer contour of all carrier frames (30, 30', 30", 30 #, 30 ∗) is, at least in sections, complementary to the inner contour of all recesses in the receiving frame, characterised in that the insertion edge of the receiving frame is a side edge of the receiving frame, whereby the at least one carrier frame (30, 30', 30", 30 #, 30 ∗) can be removed laterally from the receiving frame, and whereby at least one carrier frame (30#) has, on at least one narrow side, an element which can be detached from the carrier frame (30#), which element allows the opening of the at least one carrier frame (30#) to be opened towards a narrow side of the carrier frame (30#), and is designed to allow at least one contact carrier (40, 40', 40#) to be inserted into the opening from the narrow side, or whereby the opening of the at least one carrier frame (30 ∗) is open towards a narrow side of the carrier frame (30#, 30 ∗) and designed to allow at least one contact carrier (40, 40', 40#) to be pushed into the opening from the narrow side. a receiving frame; and at least one carrier frame (30, 30', 30", 30#, 30 ∗); wherein the receiving frame has several recesses, which in each case completely penetrate the receiving frame in the thickness direction and are in each case open towards an insertion edge of the receiving frame, wherein each recess defines two mutually parallel side walls (121, 122), which in each case enclose an angle of between 60° and 120° and preferably 90° with the insertion edge, wherein each carrier frame (30, 30', 30", 30#, 30 ∗) has two mutually parallel side walls (131, 132), which are designed to come into positive mechanical engagement with the parallel side walls (121, 122) of each recess of the receiving frame, and wherein at least one carrier frame (30, 30', 30", 30#, 30 ∗) further has an opening for holding at least one contact carrier (40, 40', 40#), wherein all recesses in the receiving frame have the same inner contour, and wherein all carrier frames (30, 30', 30', 30#, 30 ∗) have the same outer contour, wherein the outer contour of all carrier frames (30, 30', 30", 30 #, 30 ∗) is, at least in sections, complementary to the inner contour of all recesses in the receiving frame, characterised in that the insertion edge of the receiving frame is a side edge of the receiving frame, whereby the at least one carrier frame (30, 30', 30", 30 #, 30 ∗) can be removed laterally from the receiving frame, and whereby at least one carrier frame (30#) has, on at least one narrow side, an element which can be detached from the carrier frame (30#), which element allows the opening of the at least one carrier frame (30#) to be opened towards a narrow side of the carrier frame (30#), and is designed to allow at least one contact carrier (40, 40', 40#) to be inserted into the opening from the narrow side, or whereby the opening of the at least one carrier frame (30 ∗) is open towards a narrow side of the carrier frame (30#, 30 ∗) and designed to allow at least one contact carrier (40, 40', 40#) to be pushed into the opening from the narrow side. whereby at least one carrier frame (30#) has, on at least one narrow side, an element which can be detached from the carrier frame (30#), which element allows the opening of the at least one carrier frame (30#) to be opened towards a narrow side of the carrier frame (30#), and is designed to allow at least one contact carrier (40, 40', 40#) to be inserted into the opening from the narrow side, or whereby the opening of the at least one carrier frame (30 ∗) is open towards a narrow side of the carrier frame (30#, 30 ∗) and designed to allow at least one contact carrier (40, 40', 40#) to be pushed into the opening from the narrow side.