Allen-Bradley 1790-T0W8X 8 Relay Output Expansion Module

Product Introduction

As industrial automation evolves, the need for reliable and compact output modules becomes critical. The Allen-Bradley 1790-T0W8X 8 Relay Output Expansion Module addresses this demand by providing eight Form A, normally open relay outputs in a single, space-saving unit. Designed for use with compatible Allen-Bradley systems, this module delivers consistent performance for switching resistive loads. Each output is isolated via photocoupler, ensuring signal integrity and protecting logic circuits from high-voltage transients. Whether upgrading an existing line or building a new control panel, the 1790-T0W8X offers a straightforward solution for expanding output capacity.

Technical Specifications Breakdown

The 1790-T0W8X supports a wide output voltage range, from 5 to 28V DC at 2.0 A resistive, and handles AC loads up to 250V AC at 2.0 A resistive. This flexibility allows it to interface with various actuators, relays, and indicators. The relay type is Form A, single pole, single throw, normally open, ensuring simple on/off control. Key timing specifications include an output delay time of 10 ms maximum for both off-to-on and on-to-off transitions, providing predictable switching behavior. The field power supply requires 24V DC nominal, with a voltage range of 19.2 to 28.8V DC, and power dissipation is 2.3W at 28.8V DC per channel. Isolation between I/O and logic is achieved through photocoupler isolation, rated at 1250V AC rms, enhancing system safety. The module weighs 0.38 lbs (0.17 kg) and uses a terminal block with M3.0 screws, with a maximum screw torque of 7 lb-in.

Industry Applications

In manufacturing environments, the 1790-T0W8X excels at controlling solenoid valves, motor starters, and indicator lights. For example, in a packaging line, this module can switch multiple actuators simultaneously, with each output independently controlled via its own common (1 point/1COM). The 8 green status indicators provide immediate visual feedback, simplifying troubleshooting. In material handling systems, the module's 2.0 A per channel rating ensures reliable operation of small motors and conveyors. The photocoupler isolation protects the control system from electrical noise, making it suitable for harsh industrial settings.

Installation & Setup Guidance

Mount the 1790-T0W8X securely in a panel using the provided terminal block. Use copper or copper-clad aluminum conductors and tighten screws to 7 lb-in maximum. Connect the field power supply within the 19.2 to 28.8V DC range, observing polarity. Each output is a single-pole, single-throw relay; wire loads accordingly. Ensure the total current per channel does not exceed 2.0 A for resistive DC loads or the specified AC ratings. For inductive loads, consider external snubbers to extend contact life. Verify the module is properly grounded per local codes.

Maintenance & Reliability

Regular inspection of the 1790-T0W8X helps maintain uptime. Check for loose connections and verify that screw torque remains within specification. The expected contact life is 300 Kcycles for resistive loads and 100 Kcycles for inductive loads, so plan replacements based on switching frequency. Keep the module clean and free from dust, as contaminants can affect relay performance. Monitor the green status indicators; if any output fails to energize, check the load and wiring first. For complete technical specifications for the 1790-T0W8X, please contact BluePLC Industrial.

Selection Guide & Purchasing Advice

Before ordering, confirm that your control system supports the 1790-T0W8X expansion module. Verify the field power supply voltage and ensure adequate current capacity. Consider the load type—resistive or inductive—to match contact life expectations. BluePLC Industrial offers this module with fast shipping and expert support. Please verify current lifecycle status and availability with BluePLC Industrial before ordering. For assistance selecting the right expansion module for your application, contact our team.