1794-APB | Allen-Bradley PROFIBUS Adapter - Petro Auto Tech

Product Overview

The 1794-APB is a PROFIBUS adapter module from the Allen-Bradley Flex I/O system. It acts as a communication bridge between Flex I/O modules and PROFIBUS DP master devices like PLCs. This module enables distributed I/O architectures with high-speed data exchange.

Technical Specifications Analysis

The 1794-APB operates at a nominal input voltage of 24 VDC with an input voltage range of 19.2-31.2 VDC. It supports communication rates up to 12 Mbps via one 9-pin D-shell connector. The module draws a maximum power consumption of 400 mA and has a power dissipation of 7.68 Watts at 19.2 VDC. Thermal dissipation is 26 BTU/hour at 19.2 VDC. It provides a FlexBus output current of 640 mA maximum at 5 Volts DC. The isolation voltage is 850 Volts DC. The module supports up to eight Flex I/O modules and includes two diagnostic LEDs: STATUS and PROFIBUS, both red/green.

Application Scenarios & Usage Methods

Use the 1794-APB in manufacturing plants to connect remote I/O racks to a central PLC via PROFIBUS DP. For example, in a conveyor system, it gathers sensor inputs and controls actuators at high speed. In process control, it links field devices to a DCS or PLC. Install it on a DIN rail or panel using the 1794-NMI kit. Connect a standard PROFIBUS drop cable to the 9-pin D-shell port. Configure the communication rate up to 12 Mbps to match the network.

Installation Guide & Packing List

Mount the 1794-APB on a conductive DIN rail for proper grounding. Avoid poor conductors or corrosion-prone materials. Alternatively, use the panel mounting kit 1794-NMI. Connect the PROFIBUS cable to the 9-pin D-shell connector. The packing list typically includes the adapter module and documentation. Mounting kit sold separately.

Purchasing Advice

Buy the 1794-APB if you need a reliable PROFIBUS adapter for Flex I/O systems. Verify your network speed requirements up to 12 Mbps. Ensure your power supply provides 24 VDC within the 19.2-31.2 VDC range. Petro Auto Tech offers genuine Allen-Bradley parts with fast delivery.

Repair & Maintenance Tips

Inspect the 9-pin D-shell connector for damage or corrosion. Clean with isopropyl alcohol if needed. Check the STATUS and PROFIBUS LEDs: green indicates normal operation, red signals a fault. Store the module in a dry environment between -40 and 85 degrees Celsius. Ensure the DIN rail connection is secure and conductive.

Frequently Asked Questions (FAQs)

Q: What is the input voltage range of the 1794-APB?

A: The input voltage range is 19.2-31.2 VDC, with a nominal voltage of 24 VDC.

Q: How many Flex I/O modules can the 1794-APB support?

A: It supports up to eight Flex I/O modules.

Q: What communication rates does the 1794-APB support?

A: It supports all rates up to 12 Mbps.

Q: What type of connector does the 1794-APB use for PROFIBUS?

A: It uses one 9-pin D-shell connector.

Q: What do the LED indicators on the 1794-APB mean?

A: The STATUS LED shows module status, and the PROFIBUS LED shows network activity. Green indicates normal operation; red indicates a fault.