Functional module for a modular system, wherein the system comprises at least two functional modules which can be arranged or are arranged stacked on top of one another and/or next to one another, wherein the functional module comprises: a housing with at least one interface opening; at least one interface unit, wherein the at least one interface unit is arranged in the housing adjacent to the at least one interface opening, wherein the at least one interface unit is electrically, optically, fluidically and/or information-technologically connected to at least one functional unit arranged in the housing, wherein the at least one interface unit is formed to be coupleable to a further interface unit of a further functional module of the system in order to establish an electrical, optical, fluidic and/or information technology connection to the further interface unit; at least one protective cover which is arranged such that it can be moved between a closed position, in which the at least one interface opening of the housing is closed by the at least one protective cover, and an open position, in which the at least one interface opening is open; and a mechanic unit having an actuating member accessible from outside the housing and a transmission portion, wherein the mechanic unit is configured to transmit movement of the actuating member to at least one output member via the transmission portion, wherein the at least one output element comprises at least the at least one protective cover, wherein the mechanic unit is configured to transmit movement of the actuating element via the transmission portion to the at least one protective cover in order to move the at least one protective cover between the closed position and the open position. a housing with at least one interface opening; at least one interface unit, wherein the at least one interface unit is arranged in the housing adjacent to the at least one interface opening, wherein the at least one interface unit is electrically, optically, fluidically and/or information-technologically connected to at least one functional unit arranged in the housing, wherein the at least one interface unit is formed to be coupleable to a further interface unit of a further functional module of the system in order to establish an electrical, optical, fluidic and/or information technology connection to the further interface unit; at least one protective cover which is arranged such that it can be moved between a closed position, in which the at least one interface opening of the housing is closed by the at least one protective cover, and an open position, in which the at least one interface opening is open; and a mechanic unit having an actuating member accessible from outside the housing and a transmission portion, wherein the mechanic unit is configured to transmit movement of the actuating member to at least one output member via the transmission portion, wherein the at least one output element comprises at least the at least one protective cover, wherein the mechanic unit is configured to transmit movement of the actuating element via the transmission portion to the at least one protective cover in order to move the at least one protective cover between the closed position and the open position.