The 1791D-0B16PX is a 16 sourcing output expansion module that is part of the CompactBlock I/O Module family, manufactured by Allen-Bradley. This compact device features a built-in remote adapter, a power supply, and I/O circuits, making it ideal for system architecture laid out in limited space or requiring highly distributed I/O blocks near actuators and sensors. It offers enhanced operation without adding to the footprint and installation time, and at a lower wiring and overall cost. The rotary node address switches further reduce time and work needed in node commissioning. Plus, it has an output short-circuit protection that prevents output damage due to accidental miswiring.

The 1791D-0B16PX Expansion Module accommodates a rated device power between 10 and 30 Volts DC, supporting a wide range of power supplies at multiple voltage levels. Its autobaud detection feature allows the module to automatically match the system baud rate. This means no crashing will occur due to incorrect baud. The 16 sourcing outputs per block are grouped into two sets of eight outputs. A yellow indicator signals I/O status. The 1791D-0B16PX  module needs a 500 Volt AC isolation when the I/O is linked to DeviceNet, used in I/O group-to-group, or used in an I/O group-to-logic setup. Its expansion power is rated at a 5 Volt DC voltage and a 100 mA current, while its auxiliary power has a voltage range of 10 to 30 Volts DC with a maximum current of 4 A. In addition, it comes with an IEC IP20 type enclosure. The 1791D-0B16PX expansion block must be DIN rail mounted to meet certain specifications. When installing a base with an expansion unit, consider the length of the expansion ribbon cable. These two modules– the base and expansion, can be mounted horizontally or vertically. When mounted side-by-side, it will be obvious that the connection has been done properly by the red strip that will show on top of the ribbon cable. For vertical installations, a longer ribbon cable is needed.