Overview Of Pgm Components - Honeywell Experion PKS User Manual

2.1 Overview of PGM components

This section provides a brief overview of the major components of the PGM.
• Field Network Application (FNAPP) - The PGM does not contain a basic execution block. However, it
utilizes a set of services called the Field Network Application (FNAPP) to support the data access to and
execution of control objects. The main control objects of the PGM are the Protocol Blocks (PB) and the
Device Support Blocks (DSB). Each PB and DSB block is characterized by a set of parameters and an
algorithm. The execution of these blocks are based on event sequences (faster response). The FNAPP is
periodically triggered to consume data from the C300 and provide data to the C300.
• Device Support Block (DSB): The Device Support Block represents one of the PROFIBUS field devices
(slave devices) in the PROFIBUS network. A single PROFIBUS network can support up to 124 slave
devices. A single DSB can support up to 16 PDCs.
• Protocol Block (PBLINK): The Protocol Block represents one of the field network interfaces. The Protocol
Blocks are automatically created when a PGM block is created.
• Process Data Access (PDA) - PGM utilizes the PDA protocol for process data transfer between the C300
Controller and the PROFIBUS devices over the PROFIBUS network. The main purpose of using PDA is for
fast I/O protocol data transfer that provides optimized peer-to-peer communications between the PGM and
the C300 Controller over FTE.
• Process Data Collection (PDC) - A data structure that can store and map several input or output process data
items (channels) from a given slave device to one or more PIOMB blocks in the C300 Controller. The
PIOMB then presents data to control blocks in the CEE through a set of channels." For example, in Siemens
ET200M I/O rack, one PDC holds all real-time process data of one input or output I/O module. An I/O
module that has both inputs and outputs has two PDCs.
In PGM, each PDC represents a unique I/O module. However, if an I/O module is a mixed module (input
and output module), then the module is represented by two PDCs.
• PROFIBUS HART I/O Module Block (PBHIOMB) – This block is used for supporting HART over
PROFIBUS profile. This block represent a HART IOM in the Remote Input/Output (RIO) slave and enables
you to configure the HART devices.
• PROFIBUS HART Channel Block (PBHCHANNEL) – This channel block is used for supporting HART
configuration and monitoring. Therefore, the CMD48 data can be monitored and used for generating alarms
and events in Experion system.
• DPV1 read/write support – Device Support Blocks (DSBs) are enhanced to support DPV1 data record read/
write.
2 PROFIBUS GATEWAY MODULE (PGM) OVERVIEW
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