The 1771-IFE is an Allen-Bradley module. It is a PLC-5 Analog input module with 16 single-ended or 8 differential 12-bit inputs. The 1771-IFE input module is located in the 1771 I/O rack-1 slot and where the default input type is set as the voltage but it can be changed to current using the configuration plug. The nominal voltage input ranges for 1771-IFE module are +1 to +5V DC, 0 to +5V DC, -5 to +5V DC, -10 to +10V DC, and 0 to +10V DC. The nominal current input for 1771-IFE input module ranges are +4 to +20mA, 0 to +20mA, and -20 to +20mA. The 1771-IFE has a resolution of 12-bit binary and of 12 bits plus sign on the bipolar ranges. The 1771-IFE module comes with a 1771-WG wiring arm.

The 1771-IFE input module belongs in the C series and hence is different from series A or B. For instance, the 1771-IFE module has 6 bits or diagnostic information, and this represents 6 possible faults. The 1771-IFE is also able to return input data both below and above the range end points while at the same time allowing default scaling with both the maximum and minimum scaling vales as zero. However, the 1771-IFE has no scaling error that will be reported while it is being used. The maximum block transfers for the 1771-IFE are about 22 words in length for the BTR and 39 words for the BTW. The difference is due to auto calibration in the system. 1771-IFE input module is not compatible with 1771-AL local adapter.  With regards to compatibility, 1771-IFE input module can work with any Allen-Bradley 1771 I/O chassis.