B&R X20 Modules: X20BM11 Bus Module —

Technical Dossier

Product Details And Specifications

B&R X20 Series: Comprehensive Module Range and Technical Overview

The B&R X20 system is a modular programmable logic controller (PLC) platform developed by Bernecker + Rainer Industrie-Elektronik GmbH (B&R), headquartered in Eggelsberg, Austria. Since its commercial introduction in the early 2000s, the X20 series has achieved widespread deployment across global heavy industry sectors including petrochemical refining, nuclear power auxiliary systems, offshore oil & gas platforms, pulp and paper mills, and large-scale water treatment facilities. Its compact DIN-rail form factor, deterministic POWERLINK communication backbone, and modular I/O architecture have made it a reference standard for distributed control system (DCS) integration in process-critical environments. The X20 system operates under B&R's Automation Studio engineering environment and is fully compatible with IEC 61131-3 programming standards, enabling cross-platform portability of control logic.

The Evolution of X20 Architecture

The X20 platform was designed as a successor to B&R's earlier 2003 and 2005 system families, addressing the demand for higher channel density, faster bus cycle times, and improved EMC immunity in industrial environments. The original X20 backplane bus operates at a cycle time as low as 200 µs, with the internal X2X Link fieldbus providing deterministic, time-stamped data transfer between the CPU and I/O modules. Early X20 deployments used the X20CP1301 and X20CP1381 CPUs, which have since been superseded by higher-performance variants such as the X20CP3585 and X20CP3686, featuring ARM-based processors and expanded onboard memory. The X20 bus module family — including the X20BM11 — serves as the physical and electrical backbone of each X20 station, providing the X2X Link pass-through and 24 VDC power distribution rail that connects all I/O modules within a segment. Compatibility between X20 bus modules and I/O modules is maintained across hardware revisions, though firmware alignment via Automation Studio is required when mixing module generations. As of 2024, the X20 series is in its mature phase; B&R continues to manufacture and support the full range, with no announced end-of-life for core bus and I/O modules.

X20 Full Catalog & Functionalities (SKU List)

Bus Modules

• X20BM11: Standard X2X Link bus module, 24 VDC supply pass-through, single-width, for standard I/O modules
• X20BM15: Bus module with integrated segment power supply connection, supports higher current I/O segments
• X20BB80: 8-slot bus base for compact X20 station assembly, integrated X2X Link routing
• X20BB27: 2-slot bus base, used for terminal or end-of-segment configurations
• X20PS9400: Internal power supply module, 24 VDC, 0.96 A, for X20 station power distribution
• X20PS9402: Internal power supply module, 24 VDC, 2 A, for high-density I/O stations

CPU / Controller Modules

• X20CP1301: Entry-level CPU, 32 MB RAM, Ethernet, X2X Link master, IEC 61131-3
• X20CP1381: Standard CPU, 64 MB RAM, dual Ethernet, USB, CompactFlash slot
• X20CP3585: Mid-range CPU, ARM Cortex-A9, 256 MB RAM, POWERLINK managing node
• X20CP3686: High-performance CPU, dual-core ARM, 512 MB RAM, integrated safety controller

Digital Input (DI) Modules

• X20DI4371: 4-channel digital input, 24 VDC, 0.2 ms filter, standard density
• X20DI9371: 12-channel digital input, 24 VDC, configurable input filter per channel
• X20DI6371: 6-channel digital input, 24 VDC, high-speed, 50 µs response time

Digital Output (DO) Modules

• X20DO4322: 4-channel digital output, 24 VDC, 0.5 A per channel, short-circuit protected
• X20DO9322: 12-channel digital output, 24 VDC, 0.5 A per channel, diagnostic per channel
• X20DO6322: 6-channel digital output, 24 VDC, 2 A per channel, high-current variant

Analog Input (AI) Modules

• X20AI4622: 4-channel analog input, ±10 V / 0–20 mA, 12-bit resolution, configurable per channel
• X20AI4632: 4-channel analog input, 16-bit resolution, ±10 V / 4–20 mA, high-precision process measurement
• X20AI8221: 8-channel analog input, 12-bit, 0–10 V, compact high-density configuration

Analog Output (AO) Modules

• X20AO4622: 4-channel analog output, ±10 V / 0–20 mA, 12-bit, simultaneous update
• X20AO4632: 4-channel analog output, 16-bit resolution, 4–20 mA, for precision valve and actuator control

Communication / Fieldbus Adapter Modules

• X20IF1041-1: PROFIBUS DP slave interface module, up to 12 Mbit/s, for integration into third-party DCS networks
• X20IF10D1-1: DeviceNet adapter module, slave mode, for legacy fieldbus environments
• X20IF1091-1: CANopen slave interface, 1 Mbit/s, for motion and process network integration

Sourcing Hard-to-Find & Obsolete X20 Parts

DriveKNMS maintains a dedicated inventory program for B&R X20 series modules, including units that have been discontinued from B&R's standard production schedule or that carry extended lead times through authorized distribution channels. For process plants operating legacy X20 stations — particularly those using first-generation CPUs such as the X20CP1301 or early bus modules — DriveKNMS provides lifecycle extension support through three supply channels: new-old-stock (NOS) units sourced from decommissioned plant inventories, factory-refurbished modules with full functional restoration, and tested-used units supplied with inspection documentation. All sourced X20 modules are cross-referenced against B&R's hardware revision database to ensure backplane and firmware compatibility with the target station configuration. Emergency same-day dispatch is available for critical process shutdown scenarios.

Quality Control for the X20 Range

The B&R X20 series presents specific quality control requirements due to its X2X Link bus architecture and multi-layer backplane connector system. DriveKNMS applies a structured test protocol to all X20 modules prior to dispatch. Bus modules including the X20BM11 are tested for X2X Link signal integrity using a live X20 station with a reference CPU, verifying correct data frame transmission at rated cycle times. I/O modules undergo channel-level functional verification: digital modules are tested for correct switching logic and short-circuit protection response; analog modules are calibrated against a traceable reference source to verify linearity and offset within manufacturer specification. CPU modules are booted under Automation Studio, firmware version is recorded, and RAM/flash integrity is confirmed. All modules are inspected for backplane connector pin condition, capacitor integrity, and conformal coating status before packaging.

© 2026 DriveKNMS. All trademarks belong to their respective owners. Specifications are for reference only and subject to change without notice. Verify all parameters against official documentation before installation.