Allen-Bradley 1746-OB16E SLC 500 Output Module

1746-OB16E Digital DC Output Module

Product Introduction

The Allen-Bradley 1746-OB16E is a robust digital DC output module designed for the SLC 500 programmable controller platform. This module provides 16 discrete output points for controlling various field devices. It utilizes a 10-30 Volts DC source and is specifically built for high-current applications. Furthermore, its electronically-fused design protects both the module and the connected loads from overcurrent conditions. The 1746-OB16E offers a practical solution for machine builders and plant engineers.

Key Technical Specifications

The Allen-Bradley 1746-OB16E delivers a wide range of technical features that ensure application flexibility and system integrity. First, the module has 16 discrete outputs, each supporting either 1 amp or 0.5 amps depending on the load requirements. It operates with a 10-30 Volts DC source voltage, making it compatible with standard 24V DC industrial systems. Specifically, the total current capacity for the entire module is 8 amps, while it draws only 135 milliamps at 5 Volts DC from the backplane, which minimizes the load on the system power supply.

Additionally, each output point can handle an inrush current of 2.0 amps for 2 milliseconds, repeating every 1 second at 30 °C, which is particularly useful for driving inductive loads like relays and solenoids. The module exhibits a load-dependent signal delay of 1 millisecond for both ON and OFF transitions, ensuring timely response in control loops. Moreover, the maximum output current leakage in the OFF state is only 1mA, preventing unintended activation of connected devices. The minimum current load available on each point is also 1mA, providing clear on-off state differentiation.

Mechanical and Environmental Limits

This module is built to withstand harsh industrial environments, and its rugged construction ensures long-term reliability. For instance, it dissipates 0.388W per output point, with a total module heat dissipation of 7.6W, so proper ventilation within the chassis is recommended. Furthermore, the operating temperature range spans from 0 to 60 °C (32 to 140 °F), and it functions reliably in relative humidity conditions of 5-95% without condensation. The 1746-OB16E also carries a NEMA ICS 2-230 rating for noise immunity, providing excellent resistance to electrical interference. Meanwhile, its vibration tolerance is rated at 2.5G at 10-200Hz, and it can withstand a shock rating of 30G, making it suitable for applications with mechanical stress.

Installation Guidelines

Installing the 1746-OB16E is straightforward and follows standard SLC 500 practices. First, ensure the chassis power is disconnected before installation. Next, insert the module into any available slot in the 1746 chassis, applying firm and even pressure until it seats properly in the backplane connector. Then, secure the module by tightening the retaining screws at the top and bottom. After installation, connect the field wiring using the Removable Terminal Block (RTB), which simplifies both installation and future maintenance. Finally, verify that the wiring matches the sourcing output configuration and that the load voltage is within the specified 10-30 Volts DC range.

Packaging List

• Allen-Bradley 1746-OB16E Digital DC Output Module (1 unit)

• Removable Terminal Block (RTB) connector

• Installation instruction sheet

• Module label and identification tags

Shipping Information

All orders are shipped via FedEx, UPS, or DHL to ensure fast and reliable delivery worldwide. Tracking information will be provided upon shipment.

Frequently Asked Questions (FAQ)

Q1: What is the difference between the 1746-OB16E and the standard 1746-OB16?
The 1746-OB16E is an enhanced version that includes electronic fusing for each output point, providing better protection against overcurrent conditions. The standard OB16 does not offer this built-in protection feature.

Q2: Can the 1746-OB16E drive both AC and DC loads?
No, this module is specifically designed for DC loads only. It operates with a 10-30 Volts DC source and is not compatible with AC voltage applications.

Q3: What happens if one output exceeds the current limit?
The electronic fusing on each output point will trip to protect the module and the connected device. After the fault is cleared, the output can be reset by cycling the power or through the control program.

Q4: Is the Removable Terminal Block included with the module?
Yes, the RTB connector is included in the packaging. This allows for easy wiring and maintenance without having to disconnect individual wires.

Q5: What is the typical step response time for this module?
The 1746-OB16E has a step response of 60 milliseconds for the input side and 2.5 milliseconds for the output side, ensuring fast and accurate signal processing in high-speed applications.