Allen-Bradley 8500-E151 Digital Input/Output Module

Allen-Bradley 8500-E151 is a Series A AC digital input/output module in the 8500 I/O family, delivering 20 digital inputs and 12 digital outputs for a compatible Allen-Bradley PLC backplane. It is designed for 115 VAC operation, with an input voltage range of 85–132 VAC at 50/60 Hz, enabling direct connection to standard mains-powered sensing and control devices while remaining compatible with the 8500 backplane. The module uses triac-based AC outputs that switch loads from 85–265 VAC, allowing control of AC devices within that range from a single I/O bank. The 8500-E151 is documented as a 20-input/12-output AC I/O unit, optimized for legacy AB control architectures where a compact, centralized digital I/O solution is needed to monitor inputs and drive AC loads in industrial environments.