Description
Meta Description
Read an authentic technical breakdown of the Molex Woodhead SST-PFB-CLX-RLL PROFIBUS Master Scanner for Allen-Bradley ControlLogix platforms. Check constraints, memory modes, and RLL remote link pathways.
Main Body
Field Performance and Data Mapping Modes
During a critical packaging line expansion last winter, our plant engineering team evaluated exactly why the Molex Woodhead SST-PFB-CLX-RLL scanner card commands a premium space in the chassis. Integrating third-party Siemens drives into a Rockwell architecture requires precise cyclic data mapping. By acting as a high-performance PROFIBUS DP Master V0/V1 engine, this interface minimizes cross-network conversion delays. The module offloads all fieldbus network processing from the main ControlLogix CPU.
How does the module handle large multi-slave configurations without overwhelming the ControlLogix backplane? The card features two distinct operational data modes. Direct Mode maps up to 496 input bytes and 496 output bytes directly into the standard Logix I/O tag tree for fast execution. For larger processing footprints up to 125 slave devices, Paging Mode expands total memory access to 1,984 input bytes and 1,968 output bytes using structured array blocks managed through user-defined data structures.
Technical Specifications
- Parameter: Value
- Model Number: SST-PFB-CLX-RLL (Alternative SKU: 1120160018)
- Manufacturer: Molex / Woodhead (BradCommunications)
- Condition: New Original (New Surplus)
- Slot Width: Single Slot ControlLogix Backplane Compatible
- Communication Ports: 1 x DB9 Female (PROFIBUS DP), 1 x RS-232 (Serial Configuration)
- Maximum Baud Rate: 12 Mbps
- Protocol Capacity: DP-V0/V1 Master Class 1 & 2, DP Slave V0
- Current Draw: 850 mA @ 5 V DC or 1.75 mA @ 24 V DC
Remote Configuration Pathways and Network Boundaries
Configuring network slave trees over the backplane requires an explicit understanding of CIP path parameters. The Remote Link Library (RLL) suffix signifies that this hardware bridges directly with the legacy SST Windows Configuration Console through RSLinx. This allows remote diagnostic downloads over plant EtherNet/IP links directly to remote I/O chassis containing the scanner.
[Engineering Laptop] ---> [EtherNet/IP Switch] ---> [1756-ENBT] ---> [Backplane] ---> [SST-PFB-CLX-RLL] Is there a risk of memory synchronization loss? Well, technically it runs entirely without any custom ladder logic to move basic cyclical data, but changing your GSD setup files when the processor is running requires using an Add-On Profile (AOP) on compatible firmware versions. To ensure transmission reliability, install high-grade Belden 3079A shielded bus cables and confirm that both ends of your physical segment possess active, powered termination blocks.
Application Boundaries
Not recommended for safety-instrumented architectures requiring native PROFIsafe processing. The module lacks the internal safety-certified voting array architecture to manage emergency shutdown commands independently.
Quick Conclusions
- Bypasses custom block-transfer ladder development by using native Add-On Profiles inside Studio 5000.
- Operates efficiently up to 12 Mbps to track high-speed synchronous field machinery.
- Includes an RLL remote software feature enabling parameter adjustments over active plant networks.
- Supports dual-role capabilities acting as a DP Master and DP Slave concurrently.
FAQ
- What software is required to change the GSD slave arrangement on this module? Configuration requires the legacy BradCommunications SST PROFIBUS Configuration Tool alongside RSLinx Classic for communication routing.
- Is this card compatible with modern ControlLogix L8 Control engines? Yes, it functions correctly in standard 1756 chassis alongside L8 Series processors, though you must verify backplane power capacity.
- What do the onboard diagnostic LEDs indicate during startup? The three status LEDs indicate card health (OK), system configuration validation (SYS), and active bus line communication (COMM).
Channel Adaptation Notes
- B2B Marketplace: Highlight that this item is an obsolete/legacy hardware component from Molex Woodhead, sold in factory-sealed or tested surplus conditions.
- LinkedIn Technical Post: Focus on troubleshooting tip frameworks regarding the compilation of complex CIP routing paths over distributed control frames.
