Allen-Bradley 1756-OA16I AC Digital Output Module

The Allen-Bradley 1756-OA16I serves as an AC digital output interface for the ControlLogix platform. This module features sixteen isolated channels to drive various field devices. It operates efficiently within a wide voltage range of 75 to 265 VAC. Furthermore, the 50/60 Hz frequency support ensures compatibility with global power standards. Each output channel functions independently to prevent electrical interference between connected loads. This hardware is essential for switching actuators, motor starters, and indicator lights.

Core Technical Specifications

• Outputs: 16 Individually Isolated Points
• Voltage Range: 75–265V AC (Nominal 120/240V AC)
• Current Rating: 2A per point at 30°C (Max 4A per module)
• Backplane Current: 300mA at 5.1V DC and 2.5mA at 24V DC
• Inrush Current: 20A for 43 milliseconds per point
• On/Off Delay: Max 9.3ms at 60Hz and 11ms at 50Hz
• Power Consumption: 1.59 Watts total from backplane
• Isolation Voltage: 250V continuous (Basic Insulation)

Flexible Wiring and Configuration

Users must utilize a Removable Terminal Block (RTB) to connect field wiring. The 1756-TBCH and 1756-TBS6H housings offer secure connection points for these cables. Additionally, the software allows for granular control over fault behaviors. Each point supports “Hold Last State” or specific “On/Off” commands during communication loss. Although the module lacks internal fuses, its robust design handles high inrush currents reliably. Technicians can install this single-slot unit in any 1756-A series chassis.

Environmental and Physical Standards

This module maintains stable operation in temperatures between 0 and 60°C. It generates 18.76 BTU per hour of thermal energy during standard use. For mechanical durability, the unit withstands operational shocks up to 30G. The 1756-OA16I performs well in environments with up to 95% non-condensing humidity. While Rockwell Automation discontinued this specific model in 2012, it remains highly sought for system maintenance. Consequently, it serves as a critical spare for existing process automation lines.