Allen-Bradley 1769-IF4 Rev 2 Digital Input Module

Allen‑Bradley 1769-IF4 Rev 2 is a four‑channel, isolated analog input module for the Compact I/O family that plugs into a 1769 backplane and interfaces with CompactLogix or MicroLogix controllers. It accepts four differential or single‑ended inputs for voltage or current signals with configurable ranges including ±10 V, 0–10 V, 0–5 V, 1–5 V, or 0–21 mA (4–20 mA) per channel, with a 14‑bit resolution (unipolar) or 14‑bit plus sign (bipolar) per channel. Input impedance is approximately 220 kΩ for voltage and 250 Ω for current, and the module supports a per‑channel common‑mode range up to ±10 V with robust interference rejection (CMRR > 60 dB at 50/60 Hz when filtered; NMDR around −50 dB at the same frequencies). It is rated for 30 V AC/DC as the working voltage and provides isolation up to 500 V AC or 710 V DC per channel, with group‑to‑bus insulation specified at 30 V. The device draws about 60 mA from a 24 V supply and weighs roughly 300 g, with dimensions near 118 mm (H) × 35 mm (W) × 87 mm (D) (about 4.65 in × 1.38 in × 3.43 in). Autocalibration occurs on channel enable and configuration changes to maintain accuracy over time. Typical applications include monitoring analog signals from sensors and 4–20 mA loops in distributed control systems, RTD/thermistor setups, and other low‑voltage or current‑loop instrumentation within CompactLogix or MicroLogix architectures.