Definitions – Flowserve 400MD Logix User Manual

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Definitions

Term

Abbrev.

Defininition

Alarm

The detection of a block leaving a particular state and when it returns back to that state.

Application

A software program that interacts with blocks, events and objects. One application may interface with other

applications or contain more than one application.

Block

A logical software unit that makes up one named copy of a block and the associated parameters its block

type specifies. It can be a resource block, transducer block or a function block.

Configuration (of a system or device)

A step-in system design: selecting functional units, assigning their locations and identifiers, and defining

their interconnections.

Device

A physical entity capable of performing one or more specific functions. Examples include transmitters,

actuators, control lers, operator interfaces.

Device Description

DD Description of FBAPs within a device.

Device Description Language

A standardized programming language (similar to C) used to write device descriptions.

Device Tag

User-defined identifier for device.

Event

An instantaneous occurrence that is significant to scheduling block execution and to the operational (event)

view of the application.

FOUNDATION fieldbus

FF

Communications protocol for a digital, serial, two-way system that interconnects industrial field equipment

such as sensors, actuators, and controllers.

Function Block

FB

An executable software object that performs a specific task, such as measurement or control, with inputs

and outputs that connect to other entities in a standard way.

Function Block Application Process

FBAP The part of the device software that executes the function blocks (PID, AO, transducer, or resource blocks).

Link Active Scheduler

LAS

A device which is responsible for keeping a link operational. The LAS executes the link schedule, circulates

tokens, distributes time messages and probes for new devices.

Macrocycle

The least common multiple of all the loop times on a given link.

Manufacturer’s Signal Processing

MSP

A term used to describe signal processing in a device that is not defined by FF specifications.

Network Management

NM

A set of objects and services that provide management of a device’s communication system.

Network Management Agent

NMA

Part of the device software that operates on network management objects.

Network Management Information

Base

NMIB A collection of objects and parameters comprising configura tion, performance and fault-related information

for the communication system of a device.

Objects

Entities, such as blocks, alert objects, trend objects, parameters, display lists, etc.

Object Dictionary

OD

Definitions and descriptions of network visible objects ofa device. Various object dictionaries are contained

within a device. The dictionaries contain objects and their associated parameters which support the

application in which they are contained.

Parameters

A value or variable which resides in block objects.

Proportional Integral Derivative

Control

PID

A standard control algorithm. Also refers to a PID function block.

System Management

SM

Provides services that coordinate the operation of various devices in a distributed fieldbus system.

System Management Agent

SMA

Part of the device software that operates on system manage ment objects.

System Management Information

Base

SMIB A collection of objects and parameters comprising configura tion and operational information used for

control of system management operations.

Status

A coded value that qualifies dynamic variables (parameters) in function blocks. This value is usually passed

along with the value from block to block. Fully defined in the FFFBAP specifications.

Virtual Communication Reference

VCR

A defined communication end-point. Fieldbus commu nications can primarily only take place along active

communications path that consists of two VCR end points. For example, to establish communications

between a trans ducer AO block and another function block, a VCR must be defined at the transducer block

and a VCR must be defined at the function block between the two function blocks.

Virtual Field Device

VFD

A logical grouping of ‘user layer’ functions. Function blocks are grouped into a VFD, and system and

network management are grouped into a VFD.

Logix 3400MD Digital Positioner LGENIM3405-02 11/13

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