Description
Molex SST 5136-PFB-VME | PROFIBUS DP Master VMEbus Interface Card
Product Introduction
When a VME-based industrial computer, SCADA node, or heavy automation test rack requires deterministic communication with PROFIBUS DP field devices, relying on host CPU software stacks creates severe processing bottlenecks. The Molex SST 5136-PFB-VME is not a generic office network card; it is a dedicated industrial co-processor board built explicitly for standard VMEbus architectures. It acts as an intelligent hardware bridge that handles demanding PROFIBUS protocol execution independently.
Engineered with an onboard 32-bit microprocessor and dual-port RAM, this card handles time-critical master/slave token-passing and cyclic I/O data exchanges locally without taxing the VME backplane processor. It handles severe industrial environments—withstanding standard ambient panel operating thresholds—while delivering robust optical isolation on the RS-485 transceiver port. If you are maintaining legacy VME-based process control systems or upgrading a high-integrity rack, this module slides straight into your existing VME chassis slots.
5136-PFB-VME
Key Technical Specifications
| Parameter | Specification Metric |
| Device Category | PROFIBUS DP Master / Slave VMEbus Network Interface Card (NIC) |
| Bus Architecture | Standard VMEbus interface (A16/A24/D8/D16 support) |
| Onboard Processing | Dedicated 32-bit microprocessor with high-speed dual-port RAM |
| Network Physical Layer | Optically isolated RS-485 transceiver (PROFIBUS DP/FMS compliant) |
| Baud Rate Support | Automatic baud rate detection from 9.6 kbaud up to 12.0 Mbaud |
| Network Connector | Standard 9-pin D-sub female (DB-9F) connector |
| Isolation Voltage | 500 V RMS optical and galvanic port isolation |
| Operating Temperature | 0^\circC to +50^\circC standard industrial tier |
| Power Requirements | Powered via VME backplane DC power rails |
Application Scenarios & Pain Points
- VME-Based Industrial SCADA and DCS Systems: Plant control computers running on VME chassis architectures require direct, deterministic access to PROFIBUS remote I/O drops. The 5136-PFB-VME offloads heavy polling loops, preventing system lag.
- Petrochemical Plant Distributed Control Racks: Large-scale hydrocarbon processing skids utilize VME mainframes to coordinate field sensors and drives. This interface card ensures robust data throughput and fast network recovery during high-vibration duty cycles.
- Aerospace and Defense Test Stands: Custom laboratory testing rigs running specialized VME-based control software need stable communication with complex field machinery. The board’s onboard processor guarantees real-time master execution independent of host backplane traffic.
QA & Live Testing SOP (Trust Signal)
We don’t warehouse legacy VME communication cards without verifying their bus performance and protocol execution health; every 5136-PFB-VME unit goes through our rigorous bench protocol:
- Visual & Edge Connector Audit: Inspected under optical magnification for gold-finger trace cleanliness, surface-mount component stability, and complete absence of corrosion or solder wear on the VME pins.
- Dynamic VME Rack Testing: Slotted into an active VME test chassis to verify clean backplane power handshakes, address jumper/switch validation, and dual-port RAM read/write stability.
- PROFIBUS Network Loopback Verification: Connected to a calibrated PROFIBUS analyzer to confirm auto-baud detection across speeds up to 12 Mbaud, token-passing integrity, and zero frame errors under active polling.
- Protective Packaging: Sealed inside heavy-duty anti-static shielding bags and suspended securely within high-density structural foam to prevent transit vibration damage.
Field Engineer’s Pitfall Guide
- ❗ VME Base Address Conflicts: Verify your hardware address switch and jumper settings carefully before sliding the card into a populated VME rack; overlapping base memory addresses will lock up the system bus.
- ❗ PROFIBUS Network Termination: Ensure both physical ends of your PROFIBUS cable trunk feature active terminating resistors. Powering down a terminated drop box while the network is active will drop the bus token and crash communication.
- ❗ DB-9 Pinout Conventions: Remember that PROFIBUS uses standard pins 3 (RxD/TxD-P) and 8 (RxD/TxD-N) on the DB-9 connector; miswiring custom drop cables will prevent the transceiver from establishing a link.
Intent-Driven FAQ
Is the Molex 5136-PFB-VME compatible with both Master and Slave configurations?
Yes. The card is software-configurable to act either as a high-performance PROFIBUS DP Master controlling remote I/O drops or as a Slave node reporting to an upper-level DCS controller.
Does this card require manual address setting for VME backplane integration?
Yes. Unlike plug-and-play PCI cards, VME modules typically require proper configuration of onboard switches or jumpers to establish base memory address mapping within the chassis memory map.
What causes a red “Fault” or error status LED upon system boot?
An error status indicator typically points to a VME address conflict, an unassigned configuration file, or an incorrect bus address assignment conflicting with active network parameters.
Can multiple 5136-PFB-VME cards run in the same VME chassis?
Yes. You can install multiple interface cards in a single VME system rack to manage separate PROFIBUS networks, provided your backplane slot allocation and base address jumpers are configured independently.
What kind of warranty covers this surplus communication card?
Every unit is backed by our comprehensive replacement guarantee, supported by multi-point pre-shipment bench testing to ensure absolute VME backplane and network communication readiness.
