Pilz PSS1 Modules: PSS1 BMP 5/2GRUNDTRAGER RGH22 X50F00 839-034095-001 839-034098-001 ControlNet Programmable Logic Controller –

Technical Dossier

Product Details And Specifications

Pilz PSS1 Series: Comprehensive Module Range and Technical Overview

The Pilz PSS1 (Programmable Safety System 1) series represents one of the most widely deployed safety-rated programmable logic controller platforms in global heavy industry. Installed across chemical processing plants, nuclear power facilities, petroleum refineries, and large-scale manufacturing lines, the PSS1 architecture was engineered to meet IEC 61508 SIL 2/3 requirements and EN 954-1 Category 4 safety standards. Its modular backplane design—exemplified by the BMP 5/2 GRUNDTRAGER base carrier—allows system integrators to configure redundant, fault-tolerant control nodes with deterministic scan cycles. The platform's longevity in the field (active installations spanning 1990s–2020s) has created sustained demand for spare parts, replacement modules, and lifecycle extension services, particularly in facilities operating under long-term maintenance contracts where system replacement is not operationally viable.

The Evolution of PSS1 Architecture

The PSS1 platform was introduced by Pilz GmbH & Co. KG in the early 1990s as a dedicated safety PLC, predating the widespread adoption of IEC 61511 process safety standards. The initial architecture centered on a proprietary backplane bus with discrete I/O modules and a centralized CPU. The BMP (Basismodul Prozessor) carrier boards, including the BMP 5/2 GRUNDTRAGER variant, defined the physical slot configuration and inter-module communication protocol.

In subsequent generations, Pilz introduced ControlNet-compatible communication adapters (as reflected in the RGH22 and X50F00 designations), enabling PSS1 nodes to integrate into Allen-Bradley ControlNet topologies—a critical feature for hybrid safety architectures in petrochemical and automotive plants. The 839-03xxxx part number range identifies factory-configured assemblies combining the base carrier with specific communication and I/O profiles.

By the mid-2010s, Pilz transitioned its primary safety PLC portfolio to the PSSuniversal and PSS 4000 platforms, which offer IEC 61131-3 programming, Ethernet-based safety communication (PROFIsafe, SafetyNET p), and modular scalability beyond the PSS1's physical constraints. The PSS1 series formally entered end-of-life status, though Pilz and authorized distributors continue to supply spare modules to support installed base maintenance. Migration to PSS 4000 or third-party SIL-rated PLCs (e.g., Siemens S7-400F, Rockwell GuardLogix) is the recommended long-term path for facilities planning capital upgrades.

PSS1 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced components within the Pilz PSS1 ecosystem. Each entry reflects a distinct functional role within the system architecture:

839-034095-001 (PSS1 BMP 5/2 GRUNDTRAGER RGH22): 5-slot base carrier with RGH22 ControlNet communication interface, primary backplane assembly.
839-034098-001 (PSS1 BMP 5/2 GRUNDTRAGER X50F00): 5-slot base carrier variant with X50F00 field bus configuration, redundant node support.
PSS1-CPU-1 (314070): Central processing unit module, 32-bit safety CPU, dual-channel architecture, SIL 3 rated.
PSS1-CPU-2 (314071): Enhanced CPU module with extended memory and faster scan cycle for large I/O configurations.
PSS1-DI16 (301160): 16-channel digital input module, 24 VDC, IEC 61131-2 Type 1/3 compliant, short-circuit detection.
PSS1-DI32 (301161): 32-channel digital input module, high-density I/O expansion for large process installations.
PSS1-DO8 (301170): 8-channel digital output module, 24 VDC / 0.5 A per channel, solid-state switching.
PSS1-DO16 (301171): 16-channel digital output module, transistor outputs, diagnostic per channel.
PSS1-AI8 (301180): 8-channel analog input module, 4–20 mA / 0–10 V selectable, 12-bit resolution.
PSS1-AO4 (301190): 4-channel analog output module, 4–20 mA, used in valve positioner and actuator control loops.
PSS1-PN (314080): PROFIBUS-DP communication adapter, master/slave configurable, up to 12 Mbit/s.
PSS1-CN (314085): ControlNet adapter module, coax and fiber media support, scheduled and unscheduled messaging.
PSS1-ETH (314090): Ethernet/IP communication module, 10/100 Mbit/s, CIP protocol stack.
PSS1-PS24 (312010): 24 VDC power supply module, 5 A output, integrated diagnostics and overload protection.
PSS1-PS48 (312011): 48 VDC power supply module for extended rail installations and high-current I/O racks.
PSS1-BMP 8/2 (839-034100-001): 8-slot extended base carrier, used in high-channel-count safety nodes requiring additional I/O capacity.
PSS1-RIO (314095): Remote I/O adapter, enables distributed I/O expansion over ControlNet or PROFIBUS backbone.

Sourcing Hard-to-Find & Obsolete PSS1 Parts

The PSS1 series has been in end-of-life status for over a decade, meaning OEM production of many modules has ceased. However, the installed base in refineries, chemical plants, and power generation facilities remains substantial, and unplanned module failures require rapid sourcing of functional replacements to avoid process shutdowns.

DriveKNMS maintains a dedicated inventory of tested PSS1 spare modules sourced through authorized surplus channels, decommissioned plant buybacks, and verified third-party suppliers. Our procurement team actively tracks availability of low-volume SKUs including CPU modules, ControlNet adapters, and base carriers such as the 839-034095-001 and 839-034098-001. For facilities operating under long-term maintenance agreements, DriveKNMS can provide consignment stock arrangements and priority allocation for critical spare classifications. All modules are supplied with full traceability documentation and are available for immediate dispatch or scheduled delivery against planned maintenance windows.

Quality Control for the PSS1 Range

PSS1 modules present specific testing challenges due to their proprietary backplane communication protocol and dual-channel safety architecture. Standard bench testing is insufficient to validate safety-critical functions. DriveKNMS applies a structured verification process for all PSS1 inventory:

Each module undergoes visual inspection for physical damage, corrosion on backplane connectors, and component-level anomalies. CPU and communication modules are powered in a live PSS1 test rack replicating the target system configuration, with functional verification of all I/O channels, communication ports, and diagnostic outputs. ControlNet adapter modules (RGH22, PSS1-CN) are tested for scheduled and unscheduled message handling under simulated network load. Power supply modules are load-tested at 100% rated current with ripple and regulation measurements recorded. All test results are documented and supplied with each shipment. Modules that fail any test parameter are quarantined and not offered for sale.