The Allen-Bradley 1791P-8V8P is a CompactBlock sourcing input/sinking output base module for use with a PROFIBUS DP scanner that has 8 inputs and 8 outputs, with 4 or 8 inputs or outputs per block. Its input voltage is up to 5 Volts DC in an on-state, and in the off-state, it is as little as 10 Volts DC, as much as 30 Volts DC at 40 degrees Celsius, and as much as 25 Volts DC at 60 degrees Celsius when in an off-state. The on-state input current of this module ranges from 2 milliamps at 10 Volts DC to 11 milliamps at 30 Volts DC, while its off-state input current is at least 1.5 milliamps. In the on-state, the output has a voltage drop of 0.5V DC at the rated current and it has a voltage range of 10 to 30 Volts DC, with a maximum output current of 0.5 Amps. Its maximum surge current is 1 Amp for 10 milliseconds and is repeatable every 2 seconds, maximum module current is 0.5 Amps per output, and maximum off-state leakage is 1 milliamps. A built-in power supply is present on the 1791P-8V8P module. It also comes with a PROFIBUS adapter, 2 mounting types, status indicators a hardware watchdog function, and a hardware watchdog function.  The IEC/NEMA type 3+ inputs allow flexibility in choosing which sensors to use. The hardware watchdog function puts outputs in a known state if the microprocessor fails. The 2 mounting types allow you to install this module in any position. Lastly, the built-in PROFIBUS adapter makes an external PROFIBUS adapter unnecessary, cutting costs. The 1791P-8V8P has several international certifications, including UL-Listed Industrial Control Equipment, EN 50081-2, and EN 50082-2. Although this module is similar to the 1791P-8B8P, there are some differences. The input and output characteristics of the 1791P-8V8P are the opposite of those of the 1791P-8B8P, which has 8 sinking inputs and 8 sourcing outputs. Yet most of the input and output characteristics of these two modules are same. This module has a built-in power supply.