The Allen-Bradley 1791P-8B8P is a CompactBlock base module built for the Allen-Bradley PROFIBUS DP scanner. It comes with its own PROFIBUS adapter and requires installation on a secondary enclosure It consists of 8 sinking inputs and 8 sourcing outputs and it comes with a built-in power supply. You can group the inputs and outputs into groups of 4 or groups of 8 per block on the 1791P-8B8P. Also found on this module are a PROFIBUS adapter, 2 mounting types, a hardware watchdog function, and status indicators. The hardware watchdog function provides real-time information about microprocessor condition. This feature will tell you if there are any failings or damage occurrences on the microprocessor. The autobaud detection matches system baud rate automatically so there will be no crash because of an incorrect baud setting.

The 1791P-8B8P comes with a minimum on-state input current of 2 milliamps at 10 Volts DC to a maximum of 11 milliamps at 30 Volts DC, as well as an off-state input current minimum of 1.5 milliamps. This module also has a maximum on-state input voltage of 5 Volts DC, as well as a maximum on-state input voltage of 30 Volts DC at 40 degrees Celsius, one of 25 Volts DC at 60 degrees Celsius, and a minimum voltage of 10 Volts DC off-state input voltage. The voltage drop of the output during an on-state is 0.5 Volts DC at the rated current, while the 1791P-8B8P module’s voltage range is 10 to 30 Volts DC, with a maximum output current of 0.5 amps. It also comes with a maximum module current of 0.5 A per output, a maximum surge current of 1 amps for 10 milliseconds that is repeatable every 2 seconds, and a maximum off-state leakage of 1 milliamps.