1756-IF8A

Overview of Allen-Bradley 1756-IF8A ControlLogix Analog Input Module

The Allen-Bradley 1756-IF8A is an 8-channel analog input module for ControlLogix systems, supporting both voltage and current input signals for flexible high-density analog data acquisition. It allows per-channel configuration and offers fast, precise input measurement, making it suitable for process automation and industrial control environments.

Key Features of 1756-IF8A

• Number of Inputs: 8 single-ended (or 4 differential or 2 high-speed differential channels)
• Supported Ranges: Voltage input: ±10V, 0–10V, 0–5V DC. Current input: 0–20mA, 4–20mA
• Resolution: 16 bits (15 bits plus sign for bipolar)
• Isolation: 250 V continuous (reinforced insulation, input-to-backplane)
• Module Conversion Method: Sigma-delta ADC
• Module Error: Voltage: 0.1% of range; Current: 0.3% of range
• Input Impedance: Voltage: >1 MΩ; Current: 249 Ω
• Noise Rejection: Common-mode >100 dB, normal-mode >80 dB at 50/60 Hz
• Scan Time: 8 pt single-ended (floating point): 16–488 ms; 4 pt differential: 8–244 ms
• Accuracy: Voltage: Better than 0.05% of range @ 25°C; Current: Better than 0.15% of range @ 25°C
• Overvoltage Protection: 30V DC (voltage); 8V DC (current)
• Backplane Current Draw: 150 mA @ 5.1V, 40 mA @ 24V
• Power Dissipation: 1.73 W max
• Operating Temperature: 0 to 60°C (32 to 140°F)
• Diagnosis Features: Overrange, underrange, open-circuit, alarms

Technical Specifications

Applications / Use Cases

The 1756-IF8A module is ideal for high-density analog input tasks in process automation, manufacturing, and industrial facilities requiring accurate acquisition of voltage and current data from sensors and transmitters.