The 232-166_NR is a Wago Profi-Bus system master module. It features one PROFIBUS-DP slave port, four I/O ports, and two independent I/O nodes. The four I/O ports are designed for PROFIBUS-DP slave devices, such as fieldbus I/O modules, PLC systems, and temperature sensors. The two independent I/O nodes enable direct connection of standard I/O devices, such as switches and sensors, to the master. This module is designed for distributed automation applications, such as building automation, railway systems, and more.