ABB AC 800M controller and communication interface

Product positioning and composition

AC 800M is a rail type modular controller developed by ABB for process automation, used in 800xA systems. It consists of CPU modules, communication modules, power modules, redundant units, and accessories, covering mid to low end to high-performance control scenarios, and supporting the integration of safety and conventional automation.

Core information of CPU module

(1) Security certification

Only PM857, PM863, PM865, and PM867 have passed IEC 61508 SIL3 certification and are suitable for high integrity security applications.

(2) Performance parameters (comparison of core models)

Model Main Frequency Memory (RAM) Redundancy Supports 1000 Boolean Operations SIL3 Certification

PM851A 24MHz 8MB No 0.46ms No

PM857 96MHz 32MB is 0.17ms

PM866A 133MHz 64MB is 0.09ms No

PM891 450MHz 256MB is 0.043ms No

(3) General specifications

Power supply: 24V DC (19.2-30V DC)

Redundant switching: ≤ 10ms

Program cycle: regular * * ≤ 1ms * *, safe type 10ms

Clock synchronization: ≤ 1ms between controllers**

Environment: Working at * *+5~+55 ℃, Storage at -40~+70 ℃, Protection IP20**

Communication module (CI series)

Interface types: RS-232C, PROFIBUS DP, MODBUS TCP, PROFINET, IEC61850, EtherNet/IP, etc

Maximum mounting: CEX bus single CPU supports 12 communication modules

Universal capability: The entire series supports hot swapping, with most supporting module redundancy

Typical model:

CI854A/B：PROFIBUS DP， Dual channel, supporting cable/module redundancy

CI867/A：MODBUS TCP， Dual network ports, compatible with security controllers

CI871/A：PROFINET IO， Industrial Ethernet Master Station

Redundancy and auxiliary units

BC810: High integrity redundancy, supporting SIL3 scenarios

BC820: Conventional redundant unit, no security authentication

Universal accessories: TP830 motherboard, TK850 bus cable, SB822 external battery, SD series power supply

Compliance and Environmental Standards

Certification: CE, UL508, UL60079-15 (explosion-proof) RoHS、WEEE

Electromagnetic compatibility: EN61000-6-2 (anti-interference), EN61000-6-4 (emission)

Corrosion Protection: Compliant with ISA 71.04 G3 Industrial Corrosion Protection Grade

Key questions and answers

Question 1: Which CPUs in AC 800M have SIL3 security certification and what are the core application scenarios?

Answer: CPUs certified with IEC 61508 SIL3 include PM857, PM863, PM865, and PM867, which are used for safety related applications, process automation, and safety integration scenarios.

Question 2: What is the switching time for redundant configuration of AC 800M CPU and what is its significance for control?

Answer: Under redundant configuration, the maximum switching time is 10ms, which can ensure that the control process is uninterrupted and undisturbed, meeting the high availability requirements of industrial continuous production and safety circuits.

Question 3: What are the mainstream industrial Ethernet communication supported by AC 800M and what are the corresponding modules?

Answer: Support MODBUS TCP（CI867/CI867A）、IEC 61850（CI868/CI868A）、PROFINET IO（CI871/CI871A）、EtherNet/IP（CI873/CI873A）， Both support hot plugging and most support module redundancy.