1756-OA8 Allen-Bradley ControlLogix AC Output Module | Order Now

Allen-Bradley 1756-OA8 ControlLogix Digital AC Output Module Overview

The Allen-Bradley 1756-OA8 serves as a robust 8-point digital AC output module engineered to switch high-voltage loads ranging from 74 to 265 VAC within industrial ControlLogix architectures. Divided into two isolated groups of four channels, this module allows separate voltage tiers (such as 120VAC and 240VAC) to operate simultaneously on a single hardware card. Global PLC Spare HUB's Insight highlights this module for its flexible channel isolation, reliable programmable output delay filtering, and seamless rack integration in demanding heavy industrial control cabinets.

Model 1756-OA8 Configuration & Technical Specifications

Diagnostic Capabilities & Switching Performance

• Programmable output delay filtering supporting 9.3 milliseconds at 60 Hz and 11 milliseconds at 50 Hz.
• Last-state hold capabilities configured for both On-state and Off-state modes during fault or program transitions.
• Surge current protection handling up to 20 Amps for 43 milliseconds, repeatable every 2 seconds at 60°C.
• Scheduled output synchronization within 16.7 microseconds for time-critical AC switching applications.

Compatible Equipment & Industrial Application Sectors

• Allen-Bradley 1756 ControlLogix chassis racks including 1756-A4, 1756-A7, 1756-A10, 1756-A13, and 1756-A17.
• Inductive and resistive loads such as heavy-duty control relays, motor contactors, solenoids, and alarm sirens.
• Manufacturing assembly lines and automated material handling conveyor systems.
• Power generation balance-of-plant distribution and municipal wastewater treatment switching panels.

Packaging, Warranty & Logistics

• Industrial-grade electrostatic and shock-resistant packaging designed to protect electronic terminal pins.
• Comprehensive 12-month standard warranty covering structural and component manufacturing defects.
• Rapid 24-48 hour order processing and dispatch window.
• Global delivery services fulfilled via premium logistics carriers including FedEx, UPS, and DHL.

Frequently Asked Questions

What is the primary engineering benefit of the split-group architecture on the 1756-OA8 module?

It features two independent groups of four channels with uncommitted commons, allowing one group to switch 120 VAC while the other switches 240 VAC simultaneously.

Why is external fusing strongly recommended when installing this AC output module?

The module does not include internal channel-level fuses, so external fusing matched to the specific load current rating must be added to protect field wiring.

How does utilizing a Removable Terminal Block (RTB) simplify maintenance downtime?

The RTB allows all field wiring to remain permanently terminated to blocks like the 1756-TBCH, enabling instant module replacement without unbolting individual wires.

What factors should engineers consider regarding module current derating at high temperatures?

Total module current must be linearly derated from 5 Amps at 30°C down to 4 Amps at 60°C to prevent excessive internal thermal accumulation in tightly packed chassis enclosures.

How should I select between different compatible terminal block options for this module?

Verify whether your cabinet wiring standard requires cage-clamp or screw-clamp connections provided by variants like the 1756-TBNH or 1756-TBSH.

Tags