Description

The Allen-Bradley 1756-OA16I is a 16-point AC digital output module designed for the ControlLogix programmable automation controller platform. This module provides individually isolated output channels for switching 120/240V AC loads, ensuring electrical separation between channels and the backplane to prevent ground loop issues and fault propagation. Each of the 16 outputs is independently isolated, allowing the module to switch loads at different AC potentials or phases. The module features zero-crossing switching to minimize electromagnetic interference (EMI) and inrush current.

Features

• 16 individually isolated AC output channels
• Operating voltage range: 74 to 265V AC (47 to 63 Hz)
• Pilot duty rated at 2A per point (derated at higher temperatures)
• High surge current capability (20A for 43ms)
• Scheduled outputs with configurable fault states
• 250V continuous isolation voltage
• Triac output technology for reliable switching

Applications

• Heavy Manufacturing: Control of AC motors and conveyors with differing ground potentials
• Oil & Gas / Chemical Processing: Fault-isolated control for solenoids and actuators
• Packaging and Assembly: Switching 120/240V relays and high-inrush loads
• Critical Facility Systems: HVAC, Air Handling Units (AHUs), and emergency power transfer

Technical Specifications

Installation Guidelines

• Handling: This module is sensitive to electrostatic discharge (ESD). Use a grounded wrist strap when handling.
• Mounting: Install in a ControlLogix chassis. Ensure the module is fully seated and the locking latch is engaged.
• Wiring: Begin wiring from the bottom terminals and work upward. Use the 1756-TBE or 1756-TBEXT extended-depth housing if using heavy gauge wires.
• Strain Relief: Secure wires into the strain relief area at the bottom of the Removable Terminal Block (RTB) using a tie wrap.
• Safety: Always power down the chassis backplane before inserting or removing the module.

FAQ

What does the 'I' in 1756-OA16I stand for?

The 'I' indicates that the module features individually isolated outputs. Each of the 16 output points has its own separate return, allowing you to control devices using different voltage potentials or phases without electrical interaction between channels.

What is the response time?

The signal delay from OFF to ON and ON to OFF is 9.3 ms at 60 Hz and 11 ms at 50 Hz.

What are the current limitations?

The module supports a maximum total current of 5 A at 30 degC and 4 A at 60 degC across all 16 points. Individual points are rated for 2 A at 30 degC, derating linearly to 1 A at 60 degC.