Description
The Molex SST-PFB-SLC (often branded under SST or Woodhead) is a specialized communication interface module designed for Allen-Bradley SLC 500 programmable logic controller (PLC) systems.
Core Function
Its primary purpose is to act as a bridge, allowing an SLC 500 processor (typically SLC 5/03 or later) to communicate with devices on a PROFIBUS DP network.
- Role: It functions as a PROFIBUS DP Master (or DP Slave), enabling the SLC 500 to control remote I/O devices, drives, or other automation equipment that supports the PROFIBUS protocol.
- Integration: It installs directly into an SLC 500 rack as a single-slot module and draws power from the SLC backplane.
Key Technical Specifications
- Network Protocol: PROFIBUS DP-V0/V1 (Master and Slave).
- Baud Rates: Supports all standard PROFIBUS baud rates (ranging from 9.6 kbaud up to 12 Mbaud).
- Capacity: Can scan up to 96 PROFIBUS DP slaves.
- Data Handling: Provides significant data space (typically supporting up to 2064 bytes of input/output data) mapped into the SLC processor’s I, O, M0, and M1 data files.
- Physical Ports:
- PROFIBUS Port: 9-pin female D-Sub connector for network connection.
- Serial Port: 9-pin RS-232 port used for configuration and firmware updates.
- Power Requirements: Operates on 5V DC supplied by the SLC backplane (nominal consumption ~750mA).
MOLEX SST-PFB-SLC
MOLEX SST-PFB-SLC
MOLEX SST-PFB-SLC
MOLEX SST-PFB-SLC
Common Use Cases
- Legacy System Integration: It is frequently used in older manufacturing or industrial plants to integrate modern PROFIBUS-enabled field devices (like sensors, actuators, or VFDs) with existing Allen-Bradley SLC control architecture without needing to replace the entire PLC system.
- Distributed Control: Enabling a centralized SLC PLC to manage distributed I/O blocks located across a PROFIBUS network.
Important Considerations for Procurement
- End-of-Life Status: This module is a legacy product. While it remains vital for maintaining older control systems, it is no longer actively manufactured.
- Sourcing: Because it is obsolete, it is primarily available through the “New Surplus” or “Refurbished” market. When purchasing, ensure the supplier provides a warranty and verifies the module’s tested functionality.
- Configuration: The module requires specialized configuration software (ProSoft/SST Configuration tools) to set up the network mapping and parameters before it will communicate correctly with your SLC processor.
