A terminal block arrangement includes a housing and a plurality of connection terminals, each connection terminal including at least one terminal unit for contacting at least one conductor, which can be received on the connection terminal, and at least one associated actuation unit for actuating the terminal unit in order to selectively transfer the terminal unit between at least two positions. At least one of the positions is an open position and at least one of the positions is a contact position. The terminal block arrangement also includes a blocking device, wherein, in a blocking position, the blocking device is capable of preventing, jointly, the actuation of the actuation units of at least two of the plurality of connection terminals.