The Modbus module with 4 digital inputs was developed for decentralized switching tasks. It is suitable for recording potential-free switch states, e.g. electrical limit switches on ventilation flaps or auxiliary contacts on power contactors. The inputs can be connected using potential-free switches or contacts as well as voltage inputs. The inputs can be queried via a Modbus master using standard registers. The module is addressed and the bit rate and parity are set using 2 address switches on the front or via software. Suitable for decentralized installation on TH35 mounting rails in accordance with IEC 60715 in electrical distribution boards. Connection with screw terminals