Allen-Bradley 1794-OA16 120V AC Output Module

1794-OA16 Flex I/O 16-Channel AC Digital Output Module

Product Introduction

The Allen‑Bradley 1794‑OA16 module provides a flexible and robust solution for controlling AC loads in distributed I/O architectures. This digital output module features sixteen non-isolated channels that operate within a 74-132VAC range at 47-63 Hz. It interfaces seamlessly with any Flex I/O communication adapter, making it ideal for applications requiring reliable switching of relays, solenoids, contactors, and audible alarms. The module mounts on a variety of 1794 terminal bases and offers clear visual status indication for each output.

Technical Specifications

The 1794‑OA16 module delivers consistent output performance across its operating range. Its on‑state voltage spans from 74VAC minimum to 132VAC maximum, with a nominal rating of 120VAC. Each output channel can handle a continuous current of 500 mA at 55°C, while the entire module supports a total output current of 4.0 A. Additionally, the module provides a surge current rating of 7 A for 40 ms, repeatable every 8 seconds, which suits inductive loads effectively.

For signal response, the 1794‑OA16 exhibits a maximum output signal delay of one-half cycle for both OFF-to-ON and ON-to-OFF transitions. The module draws 80 mA from the FlexBus at 5V DC. It also features a maximum power dissipation of 4.7 W at 0.5 A and a thermal dissipation of 16.1 BTU/hour under the same conditions. An internal 2.5 A, 150V AC normal-blow MQ2 fuse provides built-in protection on each output.

Mechanical and Environmental Parameters

The 1794‑OA16 offers a compact footprint and broad environmental tolerance. It measures approximately 3.7 x 3.7 x 2.7 inches (94 x 94 x 69 mm) and weighs about 96 grams (3.38 ounces). Sixteen yellow status indicators on the front panel give you clear visual confirmation of each channel's active state.

Furthermore, this module operates reliably in temperatures from 0°C to 55°C (32°F to 131°F) with 5-95% non-condensing humidity. It also withstands storage temperatures from -40°C to 85°C (-40°F to 185°F). For mechanical durability, the module handles 5G vibration at 10-500 Hz and operating shocks of 30G. Its ESD immunity reaches 8 kV for air discharges. This module carries an open‑type enclosure rating and suits indoor installations only.

Mounting Base Compatibility

The 1794‑OA16 connects to field wiring through a compatible 1794 terminal base unit. It works with the following base models: 1794‑TBN, 1794‑TBNF, 1794‑TB2, 1794‑TB3, 1794‑TB3S, 1794‑TBKD, 1794‑TBNK, 1794‑TBNFK, 1794‑TB3K, and 1794‑TB3SK. For the 1794‑TBN base, auxiliary terminal blocks are necessary to connect the 120V AC common voltage source for individual channels. Meanwhile, the 1794‑TBNF base includes integrated fusing for additional protection.

Installation Guidelines

Installing the 1794‑OA16 correctly ensures safe and reliable operation. First, set the keyswitch on the terminal base to position 8, the designated setting for this module. Next, push the Flexbus connector fully to the left to establish a connection with the adjacent adapter or base.

Then, align the module's groove with the alignment bar on the terminal base. Press the module straight inward until the latching mechanism clicks securely into place. For wiring, connect each AC load to the appropriate output terminals according to your terminal base type. Also, connect the AC common and power supply leads as specified in the terminal base documentation. Remember that the outputs are not individually fused on the module itself, so you may need to use the 1794‑TBNF base or external fuses for point-level protection.

Packaging List

Your shipment for the 1794‑OA16 includes the following items:

• (1) Allen‑Bradley 1794‑OA16 Digital Output Module

Frequently Asked Questions (FAQ)

Q1: What types of loads can I control with the 1794‑OA16 module?
A1: This module drives AC loads such as relay coils, solenoid valves, contactors, pilot lights, horns, buzzers, and other devices that operate at 120V AC nominal voltage.

Q2: Does the 1794‑OA16 provide individual output fusing?
A2: No, the module itself does not include per-point fusing. However, you can use the 1794‑TBNF terminal base, which integrates fusing, or add external fuses for each channel.

Q3: Which terminal base units work with the 1794‑OA16?
A3: This module fits the 1794‑TBN, 1794‑TBNF, 1794‑TB2, 1794‑TB3, 1794‑TB3S, 1794‑TBKD, 1794‑TBNK, 1794‑TBNFK, 1794‑TB3K, and 1794‑TB3SK bases. Choose the base that matches your wiring and fusing requirements.

Q4: What do the yellow LEDs on the front panel indicate?
A4: Each yellow LED corresponds to one output channel. When the LED illuminates, it signifies that the output is actively energizing the connected load.

Q5: Can I use the 1794‑OA16 in a DC control system?
A5: No, this module is designed specifically for AC loads operating at 74-132VAC, 47-63 Hz. For DC output applications, consider other Flex I/O output modules such as the 1794‑OD16 or 1794‑OB16 series.