Allen-Bradley 1756-OA16I ControlLogix AC Isolated Output Module

1756-OA16I 16-Channel AC Isolated Output Module by Rockwell Automation

Product Introduction

The 1756‑OA16I from Allen‑Bradley is a high‑density isolated AC output module designed for the ControlLogix platform. It offers sixteen individually isolated output channels, each capable of switching 120 VAC or 240 VAC loads. This module accepts a wide operating voltage range of 74 to 265 VAC at 47–63 Hz, making it suitable for global industrial applications. Each channel is electrically isolated from the others and from the backplane, ensuring reliable performance in noisy environments and simplifying wiring for mixed load types.

Key Technical Specifications

The 1756‑OA16I delivers robust AC switching with derated current handling based on temperature. Its outputs are fully isolated, and it supports programmable fault and program states per point for enhanced safety and flexibility.

• Number of Outputs: 16 individually isolated

• Output Voltage Range: 74–265 VAC (nominal 120/240 VAC), 47–63 Hz

• Output Delay (OFF to ON): 9.3 ms @ 60 Hz; 11 ms @ 50 Hz

• Output Delay (ON to OFF): 9.3 ms @ 60 Hz; 11 ms @ 50 Hz

• Continuous Current per Point: 2 A @ 30 °C; 1 A @ 60 °C (linear derating)

• Continuous Current per Module: 5 A @ 30 °C; 4 A @ 60 °C (linear derating)

• Inrush Current: 20 A for 43 ms per point, repeatable every 2 s at 60 °C

• Minimum Load Current: 10 mA per point

• Off‑State Leakage Current: 3 mA max per point

• On‑State Voltage Drop: 1.5 V @ 2 A; 6 V for load current < 50 mA

The 1756‑OA16I draws 300 mA at 5.1 VDC and 3 mA at 24 VDC from the backplane. Total backplane power is 1.59 W, with a maximum power dissipation of 5.5 W at 60 °C and thermal dissipation of 18.76 BTU/hr.

Isolation and Protection Features

Isolation is a key advantage of the 1756‑OA16I. It provides 250V continuous isolation (basic insulation) between output channels and the backplane, as well as between individual output channels. This isolation is tested at 1350V AC for 2 seconds, ensuring safety and signal integrity. The module does not include internal fusing, so external fusing is recommended for each output circuit to protect against overcurrent conditions.

Configuration and Fault Management

The 1756‑OA16I supports flexible configuration through the Logix programming environment. You can set fault‑mode and program‑mode states per output point, with options of Hold Last State, On, or Off. The default setting is Off, which promotes safety during controller faults or program mode transitions. The module also supports scheduled output data and listen‑only communication formats.

Installation and Mounting Guidelines

Installing the 1756‑OA16I follows standard ControlLogix procedures. It occupies a single slot and fits into any available position in a ControlLogix chassis, except the leftmost slot reserved for the processor or communication adapter.

• Step 1: Ensure the chassis is powered off before installation.

• Step 2: Align the 1756‑OA16I with the card guides in your chosen slot.

• Step 3: Slide the module firmly into the backplane until it clicks into place.

• Step 4: Attach a compatible removable terminal block (RTB). The 1756‑OA16I works with 1756‑TBCH (screw) and 1756‑TBS6H (spring) 36‑pin RTBs.

• Step 5: Wire your AC loads to the RTB terminals, respecting isolation between channels.

• Step 6: Power on the chassis and configure the module using your Logix software, setting RPI, fault states, and other parameters as needed.

This module is compatible with all ControlLogix chassis, including 1756‑A4, 1756‑A7, 1756‑A10, 1756‑A13, and 1756‑A17. It can be used in local racks with a controller or in remote racks with a communication adapter.

Packaging List

Your shipment of the 1756‑OA16I includes the following:

• One (1) Allen‑Bradley 1756‑OA16I ControlLogix isolated AC output module

• Removable terminal block (RTB) – choose 1756‑TBCH or 1756‑TBS6H when ordering

• Installation instruction sheet

• Anti‑static packaging for safe transit

Note: This package does not include fuses, calibration certificates, warranty documents, or software.

Shipping and Delivery

We ship the 1756‑OA16I worldwide via trusted express carriers: FedEx, UPS, and DHL. Orders are processed within 24 business hours. You will receive a tracking number as soon as your order leaves our warehouse.

Frequently Asked Questions (FAQ)

1. What is the maximum output current per point for the 1756‑OA16I?
Each point on the 1756‑OA16I can deliver 2 A continuously at 30 °C. At 60 °C, the current derates linearly to 1 A per point.

2. Can the 1756‑OA16I switch both 120V and 240V loads?
Yes. The 1756‑OA16I accepts a wide input voltage range of 74 to 265 VAC, covering both 120V and 240V nominal systems.

3. Which removable terminal blocks are compatible with the 1756‑OA16I?
The 1756‑OA16I uses 36‑pin RTBs. Compatible models are 1756‑TBCH (screw‑type) and 1756‑TBS6H (spring‑clamp).

4. Does the 1756‑OA16I have internal fuse protection?
No, the 1756‑OA16I does not include internal fusing. We recommend installing external fuses on each output circuit for overcurrent protection.

5. Is the 1756‑OA16I hot‑swappable?
Yes, the 1756‑OA16I supports insertion under power (hot‑swapping) when used in a compatible ControlLogix system, provided the chassis and power supply support this feature.