ABB AC 800M

PM8xx/TP830 Processor Unit – General Section 1 Introduction
30 3BSE 027 941 R301
PM8xx/TP830 Processor Unit – General
Physically the PM8xx/TP830 Processor Unit consists of two basic parts:
• Processor Unit (PM856/PM860/PM861/PM864) with processor and Power
Supply boards
• Baseplate (TP830), housing the unit termination board
See Figure 4 on page 32 and Figure 5 on page 33, Functional Block Diagram. 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 CompactFlash interface (CompactFlash is not connected is this release
and intended for future use).
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 RS232-C 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 take place. 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.
24 V DC, connected to the TP830 Baseplate, power all 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 units.
PROFIBUS DP, FOUNDATION Fieldbus and dual RS232-C ports are some
examples of unit types available for connection to the CEX-bus.