ABB AC 800M Controller Hardware PM866

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 

PM8xx/TP830 Processor Unit – General

The topic does not apply to PM891. See PM891 Processor Unit – General on page 40. Physically the PM8xx/TP830 Processor Unit consists of two basic parts: 

 • Processor Unit (PM851/PM851A/PM856/PM856A/PM860/PM860A/PM861/PM861A/ PM864/PM864A/PM865/PM866) with processor and Power Supply boards. 

 • Baseplate (TP830), housing the unit termination board.

For the Functional Block Diagram, see Figure 4 on page 35 and Figure 5 on page 36. The CPU board contains the microprocessor and the RAM memory, controllers for all built-in communication interfaces, real-time clock, LED indicators, INIT push button and a Compact Flash interface.

The main function of the power supply board is to generate isolated, circuit-proof +5 V and +3.3 V supplies to the CPU and I/O units. The board also contains opto isolated RS-232C drivers/receivers for the service port, together with a back-up battery holder for memory/real time clock, (RTC).

The termination board, housed in the TP830 Baseplate, is where the majority of the external connections terminates. The board is grounded to the DIN-rail through of the metallic components of the housing. The termination board is provided with screw terminals for power supply and redundant power supply monitoring, with RJ45 connectors for the control network and serial port, a connector for the service port, the electrical ModuleBus and the CEX-Bus.

The 24 V DC supply, connected to the TP830 Baseplate, powers all the units on the CEX-Bus and the electrical ModuleBus.

In single CPU configuration, it is possible to connect an S800 I/O cluster directly to the built-in electrical ModuleBus plug located on the right hand side of the TP830 Baseplate. The processor unit has a communication expansion bus connector located on the left-hand side of the TP830 Baseplate. This CEX-Bus provides for extending the on-board communication ports with additional communication interfaces.

PROFIBUS DP, FOUNDATION Fieldbus H1, FOUNDATION Fieldbus High Speed Ethernet and dual RS-232C ports are some examples of unit types available for connection to the CEX-Bus. It is possible to use redundant communication interfaces, for example PROFIBUS DP. Figure 6 on page 38 provides examples of various ways to connect the S800 I/O units. It can be seen, at the top right-hand area of Figure 6 on page 38, that one cluster (or group) of units (maximum number of units per cluster is 12) is connected to the electrical ModuleBus of an AC 800M Controller. However, a further seven clusters (each comprising up to 12 units) can be added to the optical ModuleBus, thus achieving a total count of 96 units per AC 800M Controller when using only the ModuleBus. Connecting S800 I/O units (using the ModuleBus) to an AC 800M Controller mounted with a PM851/PM851A processor unit is restricted to, one electrical ModuleBus cluster and one optical ModuleBus cluster. To the left on Figure 6 on page 38, there is a PROFIBUS DP segment. This allows for a large increase in the numbers of units connected to each AC 800M Controller. Here the segment is shown as having an FCI unit (type CI801), connected to the PROFIBUS DP network. The use of FCI units allows the selection of units from several I/O families. Figure 7 on page 39 shows another example for I/O units based on a FOUNDATION Fieldbus High Speed Ethernet (FF HSE). For further examples refer to the relevant documentation for the I/O system in question.