„ Scalable controllers

„ Quick assembly

„ Easy-to-use

„ Field proven architecture

„ Designed for Electronic Marshalling

„ Advanced controls

Introduction

The DeltaV™ SX controller provide communication and

control functions and integrate field devices and the other

nodes on the control network. The SX and SQ controllers

provide a choice to match the controller capacity to the

requirements of the process. They also provide new ease

of use features that eliminate mounting screws and accelerate

cabinet assembly.

Control strategies and system configurations created on

earlier DeltaV systems can be used with this powerful

controller. The SX Controller provides all the features

and functions of the M-series controllers including support

for CHARM based Electronic Marshalling.

The control languages executed in the controllers are

described in the Control Software product data sheet.

Events that can cause a switchover include:

„ Hardware failure within the active card.

„ Communications failure between the active card

and the controller.

„ Detection of a fault in the field wiring.

A switchover may also be initiated from the diagnostics explorer, and the health and status of both cards and their channels are

available in the diagnostics explorer.

The system automatically commissions a new standby card. In safe areas, failed cards can be replaced under power.

In hazardous areas, appropriate installation procedures must be followed.

Switchover of a redundant I/O card is completed within

two scans of the I/O bus. Make-before-break contacts ensure

digital field instruments remain powered and the process

is undisturbed. Analog output signals are briefly driven by

both cards for <5 ms during switchover of the card.

Hardware alerts automatically report hardware integrity errors

for both the primary and secondary cards. Any event that

causes a switchover is also reported automatically through the

system hardware alerts and is logged in the Event Chronicle.

I/O Card Redundancy

Redundant I/O cards are available for critical applications.

The same card can be used in simplex or redundant

applications. When installed on a two-wide redundant terminal

block, the cards are recognized as a redundant pair by the

controller. The controller scans each card and determines which

card is acting as the active interface. When a fault is detected,

the system automatically switches to the standby I/O card.

DeltaV control modules reference simplex and redundant

I/O channels identically and there is no special configuration

required to take advantage of redundancy.

Switchover of a redundant I/O card is completed within

two scans of the I/O bus. Make-before-break contacts ensure

digital field instruments remain powered and the process

is undisturbed. Analog output signals are briefly driven by

both cards for <5 ms during switchover of the card.

Hardware alerts automatically report hardware integrity errors

for both the primary and secondary cards. Any event that

causes a switchover is also reported automatically through the

system hardware alerts and is logged in the Event Chronicle.

Switchover Detection

The redundant controllers continuously monitor themselves

and each other for conditions that require a switchover. Each

controller runs continuous self-test routines to determine their

ability to function. A hard failure of the active controller will trigger

an immediate switchover to the standby controller. The standby

controller also monitors the I/O bus traffic to detect if the active

controller stops functioning and failed to issue a switchover

command. This switchover requires a verification cycle, during

which time all output signals hold their values until the new active

controller begins executing control strategies.

Replacing an existing standby controller is as simple as removing

the existing unit and installing a new controller. The active

controller will detect the standby and the system will automatically

commission and download the new hardware. A redundancy

license is required in addition to the redundant hardware. The

redundant controller appears in the Explorer window as a single

node, indicated by a redundant controller icon.

Product Description

For critical process control applications where you can’t afford

interruptions, the DeltaV system offers controller redundancy.

The standby controller contains the same control strategies as

the active controller and the redundancy link transfers control

parameters to the standby controller to ensure it is ready to take

control if needed.

With redundancy enabled, each module will calculate the

required updates for the Standby controller when it executes.

These updates are transferred to the standby controller over

the redundancy link. These additional operations for controller

redundancy will typically reduce your CPU free time by

approximately 10%.

When a fault is detected, the standby controller can take over

without bumping the process control signals. The DeltaV Event

Chronicle stores a record of each switchover and the reason it

occurred (if the reason has been identified).

• Uninterrupted control operation

• Online upgradeable

• Automatic commissioning

• Bumpless transition

Introduction

Now you don’t have to worry about a controller hardware failure

interrupting your process and causing costly downtime. Using a

redundant controller, your process is automatically protected in

case of a hardware failure.

If an active controller fails, the standby controller takes over

automatically, providing uninterrupted control operation

without initialization or user intervention. The switchover

generates no disturbances to the field output signals, so your

process continues to run without impact. There is no special

cabling or configuration required to add redundancy, simply

add a controller to your existing hardware.

Redundant controllers also support the upgrade of controller

firmware and hardware online. You can therefore upgrade

your MD Plus to an MQ or MX or your SD Plus to an SQ or SX

controller online, with no configuration changes

Modules that work closely together to perform a specific process control function are

typically grouped in an area. An area is a logical division of a plant. Areas typically

represent plant locations or main processing functions. The configuration engineer

determines how to logically divide the plant into areas.

Nodes are physical pieces of equipment on the control network, such as a controller

or a workstation. You control your process by downloading modules in the controller

nodes. The configuration tells the node how to act and what information to receive or

save from the process.

Device Tags represent the instruments, valves, and other field devices. A Device

Signal Tag consists of a specific signal from a device.

Alarms alert the operator that an event has occurred. (Alarms are assigned to

modules.) Typically, you want the operator to perform some action and respond to the

alarm. Alarms can be both visible and audible.

The database contains configuration information and lets you make off-line changes

without affecting the process. Online control algorithm monitoring and modification

are also available.

Function blocks are building blocks for creating the continuous and discrete

algorithms that perform the control or monitoring for the process. The DeltaV

Library contains function block templates for analog control (bias/gain, lead/lag,

PID, etc.), Logical, I/O (analog and discrete input/output), and other basic functions.

Each function block contains parameters that can be modified to customize the

algorithm. Algorithms range from simple input conversions to complex control

strategies. Function blocks can be combined into composite function blocks to build

complex algorithms.

In addition to Function Block algorithms, the DeltaV system supports Sequential

Function Charts (SFCs) as well as Command-driven and State-driven algorithms

for control tasks requiring sequencing strategies.

Parameters are the user-defined data used within a module’s algorithm to perform its

calculations and logic. Parameters can be described by the type of information they

provide, such as input or output. Tables listing the parameters and their properties are

included in the Books Online information.

The DeltaV system includes a library of pre-engineered module templates with basic

characteristics. You can customize these library modules or create your own modules

from scratch. Your customized modules can be added to the library, making them

available for reuse in the development of your control strategy.

Terminology

Control strategies in the DeltaV system are configured in modules. A module, which

is the smallest logical control entity in the system, contains algorithms, conditions,

alarms, displays, historical information, and other characteristics that define the

process equipment. Algorithms are the logical steps that define how the module

behaves. The DeltaV system provides control, equipment, and unit modules.

Generally, a control module contains one uniquely tagged control entity, such as a

control loop or motor, with its associated logic. Defining a module around a single

field device and its related control logic makes it easy to create, download, operate,

debug, and take a single module out of service without affecting other modules.

Equipment modules coordinate the operation of control modules and other

equipment modules that work together to control related equipment. The algorithm

for the containing equipment module manages the operation of the contained

modules.

Unit modules can be used in non-batch applications to group control modules and

equipment modules for alarm management purposes. For example, alarms for a

specific unit, such as a boiler, can be combined. All control and equipment modules

associated with the unit will be contained within the unit module.

DeltaV System Concepts

The DeltaV system helps users create process control systems that are easy to set up,

easy to operate, consistent, and secure. To accomplish these goals, the DeltaV system

uses the following:

Plug-and-play technology for hardware configuration

A library of reusable control modules to simplify the initial configuration effort

Techniques like drag-and-drop to simplify system configuration and modification

Consistent graphical interface similar to that of the Microsoft Windows operating

environment

Integrated, context-sensitive help and online documentation

Hardware and software approaches to ensure system security and integrity

A Configuration Assistant that steps you through the configuration process,

configuring the system while teaching you the fundamentals