ABBAC 800M Controller Hardware

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Terms that uniquely apply to this User Manual are listed in the following table.

Table 1. Terminology

UL requirements for hazardous locations, the instructions in Appendix E, Standards

must be followed.

TÜV Approval

Units mentioned in this document are TÜV qualified for IEC 61508 SIL2 or SIL3 if 

the

product is marked with the TÜV logo.

Released User Manuals and Release Notes

A complete list of all User Manuals and Release Notes applicable to System 800xA 

is provided in System 800xA Released User Manuals and Release Notes 

(3BUA000263*).

System 800xA Released User Manuals and Release Notes (3BUA000263*) is 

updated each time a document is updated or a new document is released. It is in pdf 

format and is provided in the following ways:

• Included on the documentation media provided with the system and published 

to ABB SolutionsBank when released as part of a major or minor release, 

Service Pack, Feature Pack, or System Revision.

• Published to ABB SolutionsBank when a User Manual or Release Note is 

updated in between any of the release cycles listed in the first bullet.

A product bulletin is published each time System 800xA Released User Manuals 

and Release Notes (3BUA000263*) is updated and published to ABB 

SolutionsBank.

Product Overview

AC 800M – General

AC 800M is a hardware platform comprising individual hardware units, which can 

be configured and programmed to perform multiple functions.

Once configured and programmed, the AC 800M effectively becomes the AC 800M 

or AC 800M HI controller.

The hardware units that form the AC 800M and AC 800M HI Controllers are:

• Processor units (including baseplate)

(PM851/PM851A/PM856/PM856A/PM860/PM860A/PM861/PM861A/

PM864/PM864A/PM865/PM866/PM891)

• High Integrity Processor Unit

(consists of PM865 and SM810/SM811 with corresponding baseplates)

• Communication interfaces for different protocols (including baseplates)

(CI851/CI852/CI853/CI854/CI854A/CI855/CI856/CI857/CI858/CI860/ 

CI862/CI865/CI867/CI868/CI869/CI871/CI872/CI873)

• CEX-Bus Interconnection Unit

(BC810)

• Power supply units, providing various power output levels

SD831/SD832/SD833/SD834/SS823/SS832)

• Battery back-up unit

(SB821/SB822)

The SB821 is not supported with PM891.

PM851 is equivalent with PM856 unless stated otherwise.

PM851A is equivalent with PM851 unless stated otherwise.

PM856A is equivalent with PM856 unless stated otherwise.

PM860A is equivalent with PM860 unless stated otherwise

PM861A is equivalent to PM861 unless stated otherwise.

PM864A is equivalent to PM864 unless stated otherwise

When equipped with the specified Control Software, the AC 800M Controller acts 

either as a stand-alone process controller, or as a controller performing local control 

tasks in a control network consisting of many interconnected controllers, operator 

stations and servers.

Various I/O systems can be connected to the AC 800M Controller, either directly 

(S800 I/O) or via PROFIBUS DP or FOUNDATION Fieldbus.

The AC 800M is delivered without Control Software. To provide the controller 

with Control Software, first load the firmware and then create the application 

separately using the Control Builder M engineering tool.

The AC 800M Controller consists of a selection of units mounted on horizontal 

DIN-rails, which can be housed within an enclosure. The majority of units consist of 

a base mounting plate and removable cover attached with screws. 

The baseplate, which is always mounted onto the DIN-rail, carries the majority of 

the connections to processor, power supplies and communication interfaces, as well 

as the connections to the external buses and systems.

The AC 800M Controller provides a cost-effective, low-maintenance solution for 

applications ranging from small Programmable Logic Controller (PLC) to advanced 

Distributed Control Systems (DCS) control applications and combined DCS, and 

High Integrity systems control applications. 

In the AC 800M High Integrity Controller, it is possible to run both non-SIL and 

SIL classified applications. The AC 800M HI consist of PM865, SM810/SM811 

and a High Integrity version of Control Software, and is also available in redundant 

configuration. AC 800M HI requires the use of SIL certified S800 I/O units in SIL

classified applications. If the application is not SIL classified, standard S800 I/O 

units can be used with AC 800M HI controller.

Figure 1 shows the physical appearance of an AC 800M Controller with an