Product Overview

The Allen-Bradley 1746-OW8 is an SLC 500 digital contact output module. This module provides eight normally open (N.O.) relay channels. It operates at voltages from 5-265V AC or 5-125V DC. The Allen-Bradley 1746-OW8 has two output groups with four channels per common. Users trust this module for reliable relay output control in SLC 500 systems.

Technical Specifications

The 1746-OW8 delivers versatile relay output capability with group isolation. Below are the complete technical details.

General Specifications

• Manufacturer: Rockwell Automation.

• Brand: Allen-Bradley for industrial control reliability.

• Part Number: 1746-OW8 for precise identification.

• Series: SLC 500 programmable logic controller platform.

• Module Type: Digital Contact Output Module.

• Outputs: 8 normally open relay channels.

• Number of Groups: 2 output groups.

• Points per Group: 4 channels per common.

• Output Type: N.O. Relay Contact.

• Slots Occupied: Single slot regardless of installation location.

Voltage and Current Ratings

• Operating Voltage (AC): 5-265 Volt AC at 47-63 Hz.

• Operating Voltage (DC): 5-125 Volts DC.

• Current per Output (120V AC): 1.5 amps.

• Current per Output (24V DC): 1.2 amps.

• Continuous Current per Module: 16.0 Ampere AC.

• Continuous Current per Group: 8.0 A maximum.

• Backplane Current (5V DC): 85 mA.

• Backplane Current (24V DC): 90 mA.

• Total Backplane Current: 0.85-0.9 A range.

Performance Specifications

• Signal Delay (ON at max resistive load): 10.0 ms.

• Signal Delay (OFF at max resistive load): 10.0 ms.

• Step Response (In): 60 milliseconds.

• Step Response (Out): 2.5 milliseconds.

• Maximum Heat Dissipation: 3.7 Watts total.

• Heat Dissipation per Point: 0.138 Watts.

Environmental Specifications

• Operating Temperature: -25°C to 60°C (-13°F to 140°F).

• Nonoperating Temperature: -40°C to 85°C (-40°F to 185°F).

• Relative Humidity: 5-95% without condensation.

• Operating Vibration: 2g at 10-500 Hz.

• Operating Shock: 30g.

• Pollution Level: Pollution 2 per EN/IEC 0664-1 for Zone 2 environments.

Compatibility

• Fixed Style Hardware: Compatible with SLC 500 fixed systems.

• Modular Style Hardware: Compatible with SLC 500 modular systems.

• Supported Controllers: SLC 5/01, 5/02, 5/03, 5/04, and 5/05.

• Remote I/O Topology: Compatible for use in remote I/O chassis.

• Remote Chassis Slot 0: Reserved for SLC 500 communication adapter.

• Other Slots: Compatible for this module.

Certifications and Approvals

• Hazardous Location: Certified for Class 1, Division 2 operation.

• Equipment Type: Supplied as open-type equipment.

• Intended Use: Industrial environments only.

Features and Benefits

• Eliminates Interposing Relays: Module supports multiple voltage categories.

• Cost Effectiveness: Saves panel space and reduces costs.

• Surge Suppression: May be installed to maximize operating lifespan.

• Group Isolation: Two groups allow different or same voltages per group.

Safety Warnings

• Access Restriction: Enclosure accessible only by appliance or tool.

• Power Removal: Do not disconnect equipment unless power is removed.

• Area Safety: Do not disconnect in dangerous areas.

• Arc Flash Warning: Disregard may create dangerous electric arc.

Installation Guide

Follow these steps to install the Allen-Bradley 1746-OW8 correctly.

1. Power Down the Chassis: Remove all power from the SLC 500 chassis.

2. Select an Available Slot: Choose any I/O slot in the chassis.

3. Insert the Module: Slide the 1746-OW8 into the slot carefully.

4. Secure the Module: Lock using the retaining latch at the top and bottom.

5. Wire Outputs: Connect field devices to the N.O. relay contacts.

6. Observe Group Isolation: Group 1 and Group 2 can use different voltages.

7. Apply Surge Suppression: Install for inductive loads to maximize lifespan.

8. Verify Load Current: Do not exceed 1.5A at 120V AC or 1.2A at 24V DC.

9. Check Group Current: Keep each group below 8A continuous.

10. Apply Power: Turn on the chassis power supply.

11. Test Outputs: Verify each of the 8 channels operates correctly.

12. Monitor Signal Delay: Expect 10.0 ms ON and OFF transitions.

Installation Notes

• This module occupies a single slot in the SLC 500 chassis.

• The module eliminates the need for interposing relays in many applications.

• Use in remote I/O chassis requires a communication adapter in slot 0.

• Operating temperature range is -25°C to 60°C.

• This unit is certified for Class 1 Division 2 hazardous locations.

Packaging List

This unit ships as a new and original product.

• Allen-Bradley 1746-OW8 SLC 500 Digital Contact Output Module

• Product data sheet with wiring diagram

• Surge suppression application note

• Anti-static factory packaging bag

Frequently Asked Questions (FAQ)

1. How many outputs does the 1746-OW8 provide?
The Allen-Bradley 1746-OW8 provides eight (8) normally open relay outputs. These are divided into two groups of four channels per common.

2. What voltage ranges does this output module support?
The 1746-OW8 operates at 5-265V AC or 5-125V DC. The two groups allow different voltages on each group.

3. What is the signal delay time for this relay output module?
The Allen-Bradley 1746-OW8 has a signal delay of 10.0 ms for both ON and OFF transitions at maximum resistive load.

4. Which SLC 500 controllers are compatible with the 1746-OW8?
The 1746-OW8 works with SLC 5/01, 5/02, 5/03, 5/04, and 5/05 controllers. It also supports remote I/O chassis configurations.

5. Does this module eliminate the need for interposing relays?
Yes, the Allen-Bradley 1746-OW8 supports multiple voltage categories directly. This eliminates interposing relays, saving panel space and increasing cost effectiveness.