1791-N4C2

The 1791-N4C2 module is a 6-point analog module manufactured by Allen-Bradley. The Block I/O module comes with a power rating of 120 Volts AC, with up to 4 analog inputs and 2 current outputs. The 1791-N4C2 module features an input impedance of 10 Megohms and an absolute accuracy of 0.1% at 25 degrees Celsius. The unit features 2 outputs per block, with the output impedance at less than 1 ohm. The 1791-N4C2 module is manufactured to ensure compatibility with the PLC-2, PLC-3, and the PLC-5/250 programmable controllers. The 1791-N4C2 module is designed to communicate through the block transfer or a discrete transfer with various Allen-Bradley programmable controllers that connect to an I/O network. The 1791-N4C2 module also communicates with the SLC family controllers through a discrete transfer process. The 1791-N4C2 module's 4 independent inputs can be easily configured as all voltage inputs or as all current inputs.

The Allen-Bradley 1791-N4C2 module also contains a 24 Volts DC current-limited voltage source for accommodating the loop-powered current transducer inputs. The 1791-N4C2 module's voltage input is either single-ended or differential input voltage. The 1791-N4C2 module comes with two 0 to 20 milliamps rated current outputs. Therefore, if the user program is trying to write a value that is outside of the output range, the output is clamped at the maximum or the minimum value. Installation should ensure that the blocks are wired in series. Therefore, the users should avoid installing any blocks in a parallel series. Moreover, note that the number of blocks to be used depends on the user requirements and the system that is used. The 1791-N4C2 module's block throughput depends on the controller's data transfer rates. The analog block output is updated after receiving the output data from the controllers.