Product Overview
When integrating distributed I/O into a PROFIBUS DP network, the Allen-Bradley 1734-APB provides a reliable interface between the POINT I/O backplane and the fieldbus. This PROFIBUS DP Network Adapter acts as a slave on the PROFIBUS network and a master on the PointBus, enabling seamless data exchange with up to 63 POINT I/O modules. Its compact form factor and robust design make it suitable for factory automation, process control, and material handling applications where deterministic communication is required.
Technical Specifications Breakdown
Key parameters for the 1734-APB are listed below for quick reference:
| Feature | Specification |
|---|---|
| Manufacturer | Rockwell Automation |
| Brand | Allen-Bradley |
| Part Number/Catalog No. | 1734-APB |
| Series | POINT I/O |
| Module Type | PROFIBUS DP Network Adapter |
| Input Voltage | 24 Volts DC |
| Field Side Power | 400 milliamps |
| Inrush Current | 6 amps |
| Power Consumption | 8 Watts |
| POINTBus Current | 1000 milliamps |
| Power Dissipation | 2.8 Watts (at 28.8 Volts) |
| Input Overvoltage Protection | Reverse Polarity Protection |
Industry Applications
This adapter is ideal for discrete manufacturing lines where PROFIBUS DP is the backbone. In automotive assembly, it coordinates sensor and actuator data across multiple stations. In packaging systems, it handles high-speed I/O updates. The 24 Volts DC input simplifies integration with standard industrial power supplies, while the 400 milliamps field side power supports local module loads. For water treatment plants, the reverse polarity protection adds robustness against wiring errors.
Installation & Setup Guidance
Mount the 1734-APB at the leftmost position of a POINT I/O system. Connect 24 Volts DC to the input terminals, observing polarity. The adapter converts field power to PointBus power for connected modules. Ensure the total POINTBus current does not exceed 1000 milliamps. Use a SELV or Class 2 power supply to comply with safety directives. Configure the PROFIBUS address via DIP switches or software before network startup.
Maintenance & Reliability
Periodically inspect the adapter for dust accumulation and loose connections. Verify that the input voltage remains within the specified range. The reverse polarity protection helps prevent damage from incorrect wiring, but always double-check connections during maintenance. No internal user-serviceable parts exist; replace the unit if faults persist.
Compatibility & Integration
The 1734-APB integrates with any PROFIBUS DP master, including Siemens S7 and Allen-Bradley ControlLogix systems via a PROFIBUS scanner. It supports up to 63 POINT I/O modules, allowing flexible expansion. The adapter handles both cyclic I/O data and acyclic parameterization, making it suitable for complex automation architectures.
Selection Guide & Purchasing Advice
When selecting a PROFIBUS DP adapter, consider the number of I/O points and network distance. The 1734-APB is a proven choice for medium-scale distributed systems. SpareTechPLC stocks this unit and can confirm current lifecycle status. Contact our team for pricing and lead times.
Troubleshooting & Common Issues
If the adapter fails to communicate, check the PROFIBUS address and termination resistors. Verify that the 24 Volts DC input is present and stable. If the PointBus LED is off, ensure the backplane connection is secure. For persistent faults, replace the module after confirming the power supply is within specifications.
