Allen-Bradley 1771-IQ16 Discrete Input Module

The Allen-Bradley 1771-IQ16 is a 16-point digital input module for the PLC-5 system that provides isolated 24V DC input points for discrete devices such as sensors and switches, translating their on/off states into digital data that the PLC-5 controller can process for logic decisions and I/O conditioning within legacy automation architectures. As part of the 1771 I/O family and 24V DC input family, the IQ16 supports 16 independent input channels that accept 24V DC logic signals and deliver corresponding input data to the controller; its isolation designation indicates electrical separation between the input signals and the module backplane, helping protect the controller from field wiring faults. Rockwell Automation classifies the 1771-IQ16 as discontinued, with a discontinuation date of March 10, 2020, and it is no longer available for sale; users with existing PLC-5 installations may still encounter this module in the field, but future procurement and maintenance should reference current 1771-compatible options or migration paths within legacy instrumentation.