ABB PM857K02 Redundant Safety PLC | Dual Processor

PM857K02 Redundant AC 800M High Integrity Controller Package

The PM857K02 from ABB provides a complete redundant controller solution for critical automation applications. This package includes two PM857 processor units with all necessary components for high-availability operation. It delivers both process control and safety functionality up to SIL 3 when configured with safety modules.

Package Contents

• Two PM857K01 safety processor units for redundant operation
• One TK850 CEX-bus expansion cable for module connectivity
• One TK851 RCU-Link cable for redundant CPU communication
• Complete setup for immediate redundant system deployment

Controller Architecture and Features

• Dual PM857 processors with MPC866 microprocessors at 96 MHz
• Each unit contains 32 MB RAM with 22.184 MB for applications
• Integrated real-time clocks with lithium backup batteries
• Supports high-integrity functionality with SM812 safety modules
• CompactFlash interfaces for firmware management on both units

Technical Specifications

• Manufacturer: ABB
• Model Number: PM857K02 (Article 3BSE088386R1)
• Processor Type: Dual MPC866 at 96 MHz each
• Memory Capacity: 32 MB RAM per processor, 18 MB Flash PROM
• Performance: 0.17 ms for 1000 boolean operations per CPU
• I/O Capacity: Maximum 128 I/O signals in redundant configuration
• Switchover Time: Under 10 ms for seamless redundancy

Safety and Certification

• SIL 3 certified when used with SM812 safety modules
• TÜV approved for safety instrumented systems in redundant mode
• ISA Secure certified for cybersecurity protection
• IEC 61508 compliant redundant safety environment
• Enables high-availability safety and process control

Communication Interfaces

• Two RJ45 Ethernet ports per controller (CN1, CN2)
• Two RS-232C serial ports per unit (COM3, COM4)
• Supports MMS and IAC protocols over redundant networks
• 10 Mbit/s Ethernet speed with RJ-45 connectors
• Synchronized operation within 1 ms between controllers

Redundancy and High Availability

• Full CPU redundancy for continuous operation
• CEX-Bus redundancy for communication modules
• S800 I/O redundancy support for field devices
• Fast switchover under 10 ms for uninterrupted control
• Redundant power supply status monitoring

Power Requirements

• Power Supply: 24 V DC (19.2-30 V DC range)
• Power Consumption: 210 mA typical, 360 mA maximum per CPU
• Power Dissipation: 5.1 W per unit (8.6 W maximum)
• CEX Bus Supply: Maximum 2.4 A total current
• Modulebus Supply: 24V: 1.0A max, 5V: 1.5A max

Environmental Specifications

• Operating Temperature: +5 to +55 °C (+41 to +131 °F)
• Storage Temperature: -40 to +70 °C (-40 to +158 °F)
• Relative Humidity: 5 to 95% non-condensing
• Maximum Altitude: 2000 meters according to IEC/EN 61131-2
• Protection Rating: IP20 according to EN60529
• Vibration Resistance: Meets industrial vibration standards

Certifications and Compliance

• CE marked for European market compliance
• UL 61010-1 and UL 61010-2-201 for electrical safety
• cULus Class 1, Zone 2 for hazardous locations
• Marine certificates: ABS, BV, DNV-GL
• EMC: EN 61000-6-4, EN 61000-6-2
• RoHS compliance: EN 50581:2012

Physical Specifications

• Controller Dimensions: 119×186×135 mm per unit
• Package Weight: 2700 g (5.95 pounds) total
• Protection Class: IP20 for industrial environments

Installation and Configuration

• Configure with 800xA Control Builder engineering tool
• Follow Safety Manual requirements for SIL applications
• Connect RCU-Link cable between redundant processors
• Install CEX-bus expansion cable for module connectivity
• Use dual Ethernet ports for redundant network connections
• Monitor both units through LED indicators and INIT buttons
• Verify proper synchronization between redundant CPUs

Frequently Asked Questions

• What is included in the PM857K02 package? Two PM857 processors, CEX-bus cable, and RCU-Link cable.
• What safety level does it support? Up to SIL 3 with SM812 safety modules.
• What is the switchover time? Maximum 10 ms for seamless redundancy.
• How many I/O signals can it handle? Maximum 128 I/O signals in redundant mode.
• What engineering tool is used? 800xA Control Builder for configuration.
• Is network redundancy supported? Yes, through dual Ethernet ports on each controller.