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How to apply
ANSI/ISA 88 or
IEC 61512-01
Dirk van der Linden
Table of contents
1
2
3
4
5
6
7
8
What is S88? .......................................................................................................................... 3
1.1
Types of manufacturing operations ................................................................................ 3
1.1.1
Batch processes....................................................................................................... 3
1.1.2
Continuous processes.............................................................................................. 3
1.1.3
Discrete processes ................................................................................................... 4
1.2
Why S88?........................................................................................................................ 4
Strategy of S88....................................................................................................................... 5
2.1
S88 and automation......................................................................................................... 5
2.2
3-system-elements........................................................................................................... 6
2.3
Preparation ...................................................................................................................... 6
2.4
Market segments ............................................................................................................. 7
Physical model....................................................................................................................... 7
3.1
Physical model in general ............................................................................................... 7
3.2
Process cell...................................................................................................................... 8
3.3
Types of ‘trains’.............................................................................................................. 9
3.4
Unit ............................................................................................................................... 10
3.5
Equipment module ........................................................................................................ 10
3.6
Control Module............................................................................................................. 11
3.7
Equipment- or control module? .................................................................................... 11
3.8
Design physical model.................................................................................................. 11
Recipes and procedures...................................................................................................... 12
4.1
Procedures and equipment ............................................................................................ 12
4.2
Different demands, different recipes............................................................................. 12
4.3
Recipes and process model ........................................................................................... 14
4.4
Recipes and procedure model ....................................................................................... 15
4.5
Recipes: 5 categories..................................................................................................... 15
4.6
Phases and commands................................................................................................... 17
Linking recipes to equipment control ............................................................................... 17
5.1
Types of equipment controls......................................................................................... 17
5.2
Relations of S88 models ............................................................................................... 18
5.3
Communications ........................................................................................................... 19
5.4
The lower the link, the higher flexibility ...................................................................... 20
Modes and States................................................................................................................. 21
6.1
Modes............................................................................................................................ 21
6.2
States ............................................................................................................................. 21
6.3
Exception handling ....................................................................................................... 22
6.4
Allocation and arbitration ............................................................................................. 23
System specification ............................................................................................................ 23
References ............................................................................................................................ 24
How To Apply ISA 88
Dirk van der Linden
Scientific Researcher
2
1 What is S88?
S88 is a model and methodology for the design and running of flexible production control. The
maintainability is improved because of a better and universal structure. Originally, the S88
standard is made for the batch industry, but it is applicable in discrete and continuous processes
as well. S88 is a standard to improve handling production processes. But before we can introduce
the standard, we will explain the different types of manufacturing operations we know.
1.1 Types of manufacturing operations
All processes used in industry can be divided in 3 types: batch, continuous and discrete
processes.
1.1.1 Batch processes
In a batch process raw materials are putted together in specific amounts to form by mixing or by
reacting a new product. This new product can be an end-product or a semi-finished for a new
batch. During mixing or reacting phase the supply of raw materials stops. A new ‘batch’ can only
be launched when the previous batch is completed, and the formed product is transported. It is
also possible that between two batches there is a delay.
Quite often batching involves tanks or mixers wherein a specific amount of good is prepared, and
is pumped after a process-part to the next tank, and a new process-part can be started over there.
With one batch-installation you can quite often produce a lot of different products, by varying
• raw materials
• amounts
• (mixing)times
• energy supply (temperatures, pressures...)
To reach a maximum flexibility, the S88 standard is a tool.
Examples of batch processes:
• ice cream
• soft drinks
• beer brewery
• glue
1.1.2 Continuous processes
With a continuous process there is a continuous flow of raw materials, and also a continuous
flow of finished product. The launching of a continuous process requires in some cases more
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Dirk van der Linden
Scientific Researcher
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work than ‘maintaining’ the production flow. Sometimes people choose to keep a continuous
product running 24h/24h.
Examples of continuous processes:
• Production of drinkable water
• Oil refinery
• Production of electricity
• Production of plastic tubes
Also here flexibility is requested quite often. Water can be for example hard or soft, drinkable or
not. The composition of diesel has to be different during the winter than in during the summer.
Sometimes plastic tubes has to be made of alternative raw materials for different qualities, or the
thickness of the tube has to be different etc…
In these cases the S88 standard can help for a good management of flexibility.
1.1.3 Discrete processes
In a discrete process the products are made piece by piece. One piece or a specific amount of
pieces in a group are moving from one workstation to the other. Every workstation provides an
added value. Every piece has its proper identity (serial number).
Assembling cars is a discrete process. It is clear that the production of cars has to be flexible to
satisfy all the different options and demands of the customer.
Typical workstations for discrete processes are conveyers, robots, screws, bolts, etc…
Again, the S88 standard helps to realise the requested flexibility.
1.2 Why S88?
In 1996, the SP88 committee wrote the S88 standard because of the following problems:
•
•
•
•
There was a lack of a universal model for batch control
Users had difficulties in communicating their batch processing requirements
Engineers found it very hard to develop integrated solutions with equipment of different
vendors
Engineers and end-users had configuration problems for batch solutions
Except finding solutions for these problems, the S88 also wanted to reduce the cost of
automation systems. A shorter time to market and a higher flexibility would make the production
installation more competitive. The reliability of operations can be improved. A higher process
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Dirk van der Linden
Scientific Researcher
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quality and a faster development of batch recipes could help the factories to serve their
customers better.
The S88 standard provides a set of models. Although the first target was batch control, the design
of the models are universal, so that they can be used for continuous and discrete processes as
well. A clear terminology makes communication between vendors, systems integrators and endusers better. With this terminology, less misunderstandings are possible during discussions about
the processing requirements. Data structures helps to integrate solutions in a multi-vendor
environment. Parameter guidelines makes configuration of batch solution easier.
2 Strategy of S88
Experts on different fields have to cooperate, but think in another way. Process engineers focus
on how to handle the material flow to meet the specs of the end-product. Control system experts
focus on how to control equipment. S88 makes a separation of recipes and equipment. Recipes
are to be developed by process engineers, and control system experts will have to let the
equipment run, following the parameters and procedures of the recipes.
Programming the ‘normal operation’ is often a small part of the job. More code is written for
abnormal events or exceptions. Non-structured handling of these unexpected events or workaround makes code difficult to read and to maintain. S88 provides guidelines for exception
handling.
When there is a problem with a end-product and someone wants to know the circumstances of
the production, S88-aware software can track the state of the batch. Sometimes this is integrated
in historian software.
The terminology and models makes it easier to write system requirements and to communicate
with customers and vendors. Collect all the necessary unequivocal information to produce
product and installation documentation is easier if based on a standard terminology.
For large companies it can be handsome to reproduce the same installation on another site when
the installation is based on standard models. Overall validation procedures will be more generic.
2.1 S88 and automation
S88 is not demanding any level of automation. The standard is designed to handle all levels of
automation. S88 can be applied to a full-automatic system or a full-manual system. Everything in
between (semi-automated systems) is also possible.
In terms of operation full automatic means that an operator has hardly anything to do, while a
full manual system every step in the procedure is triggered by an operator. For a semi-automated
system, the system is suggesting to proceed to the next step, but the operator has to acknowledge
every transition.
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Dirk van der Linden
Scientific Researcher
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2.2 3-system-elements
To develop a control system as a ‘good engineering’ project, you should define three important
elements:
•
•
•
How to make the product (recipes)
What physical tools are needed (equipment)
How to run the equipment (control activities)
We will come back on these three elements later.
2.3 Preparation
Before starting developing a control system, you should collect detailed requirements
information. The first step has to do with the desired flexibility, or more concrete: a list of all the
product variants needed. The different product variants are listed in recipes.
This is a question of management. There a more limits than only production flexibility. Even if a
system is for example able to produce both soft drinks and beer, a manager will rather decide
what the company is going to sell in stead of making things more flexible than needed. Besides,
in general the more flexible a system is, the more complex it will be. For the maintenance and
usability, it is better not to make a system more complex than needed.
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Dirk van der Linden
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With this list there should come a meeting with PLC or DCS programmers and process experts.
In this meeting, the previewed product variants, the knowledge of process experts and equipment
experts should be converted to a recipe structure and equipment procedures, operations and
phases.
The recipe structure should match the equipment control elements with an unequivocal interface.
This interface corresponds with the control recipe.
2.4 Market segments
Depending on the requested flexibility in terms of product variants there are 4 market segments
to define:
Segment 1: fixed sequencing, with no variations at all.
Segment 2: For every product the same procedure, but you can have multiple products by
varying formula parameters.
Segment 3: Procedures may vary, and also formula parameters can vary. The set of product
variants becomes rather high.
Segment 4: With multi-path processing equipment can be shared. The amount of product variants
remains the same as segment 3, but the production installation can become cheaper because
expensive equipment can be shared.
3 Physical model
3.1 Physical model in general
Equipment is modularized by using the Physical Model. This model has a hierarchy of seven
levels . It gives an overview of what equipment is available in the company. Based on this
overview, people can define the possibilities of an installation.
The three highest levels, Enterprise, Site and Area are important for the administration, but less
important for the design of a production installation. More details about these levels can be found
in the standard S95.
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The four lowest levels, Process Cell, Unit, Equipment Module and Control Module are important
for the production installation. Every physical component of an automated control should match
one of these levels.
3.2 Process cell
A process cell contains all the units and equipment needed to make a batch or product. A process
cell may contain more equipment than needed for a individual batch. Whether or not which
equipment is used is decided by the recipe.
For batch processes the term ‘train’ is often used to describe the path of the material flow
through various equipment. For discrete processes the term ‘line’ is often used.
In one process cell we can have several ‘trains’.
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Scientific Researcher
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3.3 Types of ‘trains’
Three types of ‘trains’ are possible:
In a ‘single path train’ the material flow is passing always the same equipment or units. The
recipe can specify some variations, but cannot change the sequence how the material flow is
passing the units.
In a ‘multi path trains’ the material flow can pass different alternative units, depending on the
recipe.
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Scientific Researcher
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In a ‘network path train’ the sequence in which the material flow passes different units can have
a lot of variations. The recipe needs a structure which can handle these complex variations.
3.4 Unit
The term ‘unit’ is more or less abstract with respect to the equipment associated with it. The unit
can perform activities which provides an added value to the product. In other words, a unit is a
manufacturing tool together (or not) with instrumentation and associated equipment.
While designing a production installation, you have to ‘find’ the units. If the equipment needs a
recipe to run, it is a unit. If the equipment do not needs a recipe to run, then it belongs to a unit.
With this, you decide the flexibility. A unit is performing a major processing activity.
A unit is active on a part or on the entire batch. No two batches can be handled simultaneous in
the same unit, a unit can only be active on one batch at a time. Every unit works independent of
other units, based on their proper unit procedures and formula parameters.
A unit contains an amount of equipment modules and control modules.
3.5 Equipment module
The S88.01 standard defines an equipment module as “a functional group of equipment that can
carry out a finite number of specific minor processing activities”. In other words, equipment
modules group physical devices for performing one or more specific functions. An equipment
module may be made up of control modules or other equipment modules.
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Scientific Researcher
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An equipment module contains all the equipment and control functions needed to carry out his
process function.
Several units can share equipment modules, eg several tanks can share the same pipeline and
pump. If an equipment module can work with only one unit at a time, it is called an ‘exclusive
use resource’. If it can act simultaneous for more than one unit, it is called a ‘shared use
resource’.
In spite of the above, an equipment module belongs in general to one unit. This applies also for
control modules.
3.6 Control Module
From a control standpoint a control module is treated as a single entity. Each control module
provides a direct connection to the process through actuators and sensors. A control modules
belongs to the physical model, but all parts are not necessary physical. A part can be a PLCsubroutine.
In the simplest form, control modules can just be devices drivers, but they can provide robust
methods of device control too, including functions like automatic and manual modes, simulation
mode, permissives or lockings, alarms.
In contrast to an equipment module, a control module cannot execute recipe procedures.
Instrumentation can be used by several control modules, eg two control modules ‘dose water’
and ‘dose cream’ can use the same flowmeter as a common instrumentation. A control device (eg
valve, motor) must be controlled by one (and only one) control module.
3.7 Equipment- or control module?
Sometimes it is not easy to decide whether a device is an equipment module or a control module.
This depends on the functionality. Control modules may not execute commands from recipes,
while equipment modules can. Equipment modules are the smallest entities on which a recipe
can act.
3.8 Design physical model
The design of the highest levels are often easy, in case you are designing an S88 physical model.
In case the design makes part of a S95-S88 project, these highest levels needs for the S95 part
more details. For us, the enterprise level stands for the company, the site stands for the
establishment, and the area stands for the production plant.
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Dirk van der Linden
Scientific Researcher
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The lower levels can be found if you concentrate on material flow, and look at your plant layouts
and process and instrumentation drawings (P&IDs). You have to determine the process cell
boundaries. Remember that a ‘train’ or ‘line’ may not exceed these boundaries. Use this rule to
check intuitive design. The material flow is passing trough one or more units in a train or line.
Each unit is a functional group of equipment which runs recipes-tasks.
The physical model is collapsible. A process cell must contain at least one unit. Other levels may
contain something. Take care that the physical model is designed in function of the equipment.
4 Recipes and procedures
4.1 Procedures and equipment
One of the key-points of S88 is the separation of process aspects in function of the people who
are working with it.
We have for example the R&D group, which is defining properties of a product by way of a
procedure. Equipment is not really important, it just has to be suitable for the procedure-course.
The engineering group is strongly involved in the equipment, but not specific which equipment
is used for a specific batch.
The production team has a large interest in where and when specific equipment is available at a
certain time to produce.
4.2 Different demands, different recipes
The knowledge to make a product is stored in recipes. S88 defines 4 types of recipes, sorted from
general to detailed. In general is written how the product can be made in principle, independent
of the production installation. The most detailed recipe is describing how the product can be
made with a specific production installation, taking into account the available machines and/or
storage capacity.
In the general recipe the principle of production is documented. These are a sequence of actions
and the proportions of raw materials. Besides the circumstances of the production (eg
environment temperature, sterile equipment for pharmacy, etc..).
The site recipe differs from the general recipe on aspects which has to do with region. For the
assembling of cars this means for example the wheel at the left for England or Australia, and at
the right for other regions. In Brazil some cars can drive with alcohol, while this fuel is not
available in other regions. A refrigerator needs more power for a tropical end-user than in
northern regions. Also the voltage of electric apparatuses can differ.
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Scientific Researcher
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A master recipe is targeted to a process cell and maybe derived from either a general or a site
recipe. The master recipe can contain product-specific information required for detailed
scheduling, such as equipment requirements. The master recipe takes into account the type of
equipment. But unlike the general and site recipe, S88 control requires a master recipe. A master
recipe is the template for control recipes used to create individual batches.
A control recipe is used to create a single, specific batch. It starts as a copy of a master recipe
and is modified as necessary to create a batch. The modifications may account for batch size,
characteristics of raw materials on-site, or actual equipment to be used.While several batches
may be derived from the same master recipe, every batch has a single control recipe to that batch
and that batch alone. Two control recipes may be indentical in ingredients, quantities, or
equipment used, but they are identified individually nonetheless. This allows product tracking
and tracing.
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Scientific Researcher
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4.3 Recipes and process model
General and site recipes are focussing rather on process activities than referring to specific
equipment. For this reason, the master and control recipes are not based on the same model.
Process
Process stage
Process operation
Process action
The general and site recipes are based on the process model, this model is used in an R&D
environment. With this model, the necessary steps to make a product can be defined.
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Dirk van der Linden
Scientific Researcher
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4.4 Recipes and procedure model
Procedure
Unit Procedure
Operation
Phase
The master and control recipes are based on the procedure model. This model is specific for a
process cell.
4.5 Recipes: 5 categories
A recipe contains the necessary set of information that uniquely defines the production
requirements for a specific product. S88 defines 5 categories of information for a recipe:
Header: administrative information and a process summary. The administrative information may
include recipe and product identification, the recipe version, the recipe author, the issue date, a
revision history, approvals and status.
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Formula: process inputs and outputs, parameters.
Process Inputs
Process
Parameters
Process
Process Outputs
A process input is the identification and quantity of a raw material or other resource required to
make the product. It can also include energy or human labour.
A process parameter details information such as temperature, pressure or time that is pertinent to
the product. Process parameters can be measured values, or set points in PID loops.
A process output is the identification and quantity of a material (product) that results from one
execution of the recipe.
Equipment requirements: the equipment category constrains the choice of the equipment that will
be used to implement a specific part of the procedure. In the general and site recipes, the
equipment requirements are typically described in general terms. At the master recipe level, the
equipment requirements specifies allowable equipment in process cells. The control recipe may
include specific allocations of process cell equipment.
Recipe procedures: sequence or strategy to execute the process. The general and site recipe
procedures are structured using the levels described in the process model since these levels allow
the process to be described in non-equipment specific terms. The master and control recipe
procedures are structured using the procedural elements of the procedural control model, since
these recipes deal with equipment classes or specific pieces of equipment.
Other information: everything what is not included in the other categories like safety
information, packaging or labelling information.
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4.6 Phases and commands
A phase is the lowest level of the procedure model. There are two versions of a phase. A recipe
phase is abstract, it is managed by recipe-software (database). An equipment phase is defined for
specific hardware. In fact an equipment phase can be a subroutine of software which is
controlling the equipment. Mostly equipment phases are programmed in PLC or DCS systems. A
phase can be a function block in a PLC project.
Physical entities (equipment modules, control modules, units) can get commands of many
phases. The status of equipment entities can change after they received a command (eg a pump
starts or stops). Programmers should take care of contradictory commands for the same
equipment. Sometimes priority management is needed. It can be part of a PLC program to
manage (many) phase commands to one control module command.
5 Linking recipes to equipment control
At some point, the rather abstract recipes must be linked to the equipment control. This link has
influence on both flexibility and complexity of the system. We will discuss the different aspects
needed to decide how this link should be made.
5.1 Types of equipment controls
In the world of S88, there are three types of control: basic control, procedural control and
coordination control.
Basic control comprises the control dedicated to establishing and maintaining a specific state of
equipment and process. This includes:
• Regulatory control: a system of control that attempts to maintain one or more process
variables at or near a desired value.
• Interlocking: to prevent a function from starting or to stop or hold a function.
• Monitoring: control to monitor a process and trigger an alarm if a variable falls out of a
specific range.
• Exception handling: taking alarming one step further, trigger an exception-handling
function.
• Repetitive discrete or sequential control: similar to regulatory control but is oriented
toward a given state (eg open or close) rather than a given value.
Procedural control directs equipment-oriented actions to take place in a given sequence in order
to carry out a process-oriented task. In other words, procedural controls manages sequences. It
can be automatic, but an operator can also execute a manual procedure.
Coordination control directs, initiates and/or modifies the execution of procedural control and the
utilization of equipment entities. They manage equipment resources, allocates equipment to
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batches, and arbitrates requests for equipment allocation in case more than a single procedure
needs the equipment simultaneously. When a procedural element comes in hold, a coordination
control can propagate the hold state up and down the procedural chain.
5.2 Relations of S88 models
While general and site recipes are based on the process model, and master and control recipes on
the procedural model, there is a relation between these models. Besides, procedural elements are
commanding physical entities by the use of controls. This actions make part of the relation with
the physical model.
A procedure is taking place in the process cell. This corresponds with the process of the process
model. Each of the lower procedural elements can take place in a unit, and corresponds with a
similar level in the process model.
A phase can also take place in an equipment module, and corresponds in this case with a process
action. A control module cannot receive commands directly from a recipe procedure, but is
commanded via an equipment module.
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5.3 Communications
In an automation project, pretty often different systems has to operate in a multi-vendor
environment. An S88 based system needs a lot of communication to let the relations between the
models work. OPC is a very successful standard in industrial communication to help commercial
hard- and software products communicate smoothly. We highlight some typical communications
needed in an S88 based system.
Process equipment is connected to a PLC, often with a fieldbus. The control modules are not
only hardware, very often the hardware corresponds with a function block in the PLC. The basic
controls of these control modules are connected via OPC to an HMI or SCADA software on a
PC. In this SCADA system, every control module is visualised with a dynamic symbol. Software
faceplates are often used to let the operator interact on the commands and settings of the control
module, while the states and actual values are used to change the colour or size of the visual
object.
The control module in the PLC is supervised by SCADA, but also by an equipment module,
which corresponds with a PLC function block too. Like the control module, the basic controls of
the equipment module is also corresponding with a dynamic object in HMI or SCADA software.
The recipe in the PC can call a phase in the PLC via the Phase Logic Interface, which is a set of
parameters to control the equipment.
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Dirk van der Linden
Scientific Researcher
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5.4 The lower the link, the higher flexibility
S88 suggest that a batch management and an equipment control system should exist separately.
The batch management system will handle elements of the control recipe procedure, and the
equipment control system will handle elements of the equipment control procedure.
For batch processes, the most common link is the phase level link. But the linking does not have
to be done at the phase level. In general, the lower the link, the more flexibility the recipe
manager can have. Keep in mind that flexibility makes things more complex too.
Some commercial batch management software packages do not allow linking on another level
than phase level. In this case, it is easy to workaround this because collapsing recipes is allowed
following S88. Skipping levels can always be done(eg definition of one operation which contains
one phase in a unit procedure).
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Scientific Researcher
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6 Modes and States
The status of equipment entities and of procedural elements may be described by their modes
and states. Modes specify the manner in which these transitions take place; states specify their
current status.
6.1 Modes
A mode determines how procedural elements (such as unit procedures and phases) and
equipment entities (such as equipment modules and control modules) respond to commands and
how they will operate.
S88 suggest 3 modes for procedural elements:
• Automatic: The transitions within a procedure are carried out without interruption as
appropriate conditions are met.
• Semi-automatic: The procedure requires manual (operator) approval to proceed after the
appropriate conditions are fulfilled.
• Manual: the procedure elements and their order of execution are completely specified by
the operator.
S88 suggest 2 modes for equipment entities:
• Automatic: Equipment entities could be under the control of a procedure or some control
algorithm.
• Manual: equipment entities are under the control of an operator.
6.2 States
S88 suggests a common set of states and transition commands for procedural elements. The
standard does not require any particular set of states and commands, but remember the S88
committee members have a lot experience, and the examples procedural states and commands
they chose probably will work in more than 95 percent of the cases.
The most elementary states are Idle-Running-Complete. This is what is called ‘normal
operation’.
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The other states and commands are suggested to use for exception handling.
6.3 Exception handling
Life of engineers would be much easier if all production systems ran perfectly from start to
finish. In practice, production systems just don’t behave as we would hope in theory. An event
that occurs outside the normal operation is commonly called an exception. Handling these
exception is an essential function of manufacturing operations and typically account more that
half of the design and engineering job.
Often exceptions are break downs, like a tripped pump, stuck valve, or a lack of steam. In this
case an operator will probably be needed to handle the exception. But also a tank running out of
an ingredient in the middle of a production could be considered as an exception. This might be
handled automatic. An event can be detected, evaluated, and a response can be generated.
Exception handling can occur in procedural, basic, or coordination control. Exception handling
can be done in procedures or in equipment control. In general, exceptions should be handled on
the level where they occur.
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6.4 Allocation and arbitration
One of the reasons why companies wanted to make their production installations more flexible,
is that control equipment is often expensive. So they want to share equipment for different
batches. Sometimes, when equipment brakes down, it can be vital that you have substitute
equipment on hand. To manage the use of shared equipment, the concepts allocation and
arbitration are introduced.
Allocation means that shared equipment is allocated to a unit by coordination controls.
Obviously a more or less abstract recipe procedure can work with alternative pieces of
equipment.
When more than one unit wants the same (shared) equipment on the same moment, priority
management can be implemented by arbitration.
7 System specification
S88 is not a compliance document. That is, you do not have to follow every letter of the standard
to say you are S88-aware. But neither do S88 software vendors. This is why there are such a
wide variety of S88 implementations in industry. Use this to your advantage by balancing the
concepts in S88 against what is practical and economically for you operations. The result of this
exercise should become a system specification document.
First, you should document the physical equipment needed or available if you are retrofitting an
S88 solution into an existing system. Collect all the P&ID’s (process and instrumentation
diagrams), electrical drawings and information system requirements. Find your units, determine
where your equipment modules and control modules are, and determine which independent tasks
equipment entities are performing.
Second, you should design master recipes using S88 definitions: header, equipment
requirements, procedure, formula, and other information. If you already decided to use a
particular S88 commercial software package, it may be easier to specify recipes based on the
capabilities of that package.
A very large part of the documentation work is describing equipment control. The definitions of
phase logic, modes and states, allocation and arbitration, exception handling, etc. are very
important, because it determines at the end how the equipment will physically run.
Other documents may describe scheduling, production history, data collection, reports, etc..
Finally, the more control engineers and IT professionals communicate, the better off. It is often
found that basic problems arise because of misunderstandings over terms. Just as S88 has helped
define common terminology for batch manufacturing, another ISA committee, SP95, is defining
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models and terminology for the purpose of integrating control systems with information systems.
For a totally integrated system, the S88 and S95 systems should match. Developing a clear,
detailed documentation is a good start.
8 References
[1]
Applying S88 : Batch Control from a User’s Perspective, Jim Parshall and Larry Lamb, ISBN 1-55617-703-8, Printed in the USA, August
2005
[2] S88 implementation guide: strategic automation for the process industries, Darrin W. Fleming, Velumani A. Pillai, ISBN 0-07-021697-5,
Printed in the USA, 1999.
[3] Applying ISA S88 to Small, Simple Processes, Clark Case, Rockwell Automation, World Batch Forum conference 13-15 nov 2006, Zemst,
Belgium
[4] S88 for Researchers and Scientists, Zofia Verwater-Lukszo, Delft University of Technology. White paper written for World Batch Forum
June 2004.
[5] Using Basic Control to Make Recipes Simple, Francis Lovering, ControlDraw Ltd, World Batch Forum conference 13-15 nov 2006, Zemst,
Belgium
[6] ANSI/ISA-S88.01-1995, Batch Control, Part 1: Models and Terminology, ISBN: 1-55617-562-0, Printed in the USA, 1995
[7] OPC Data Access Custom Interface Specification 3.0, OPC Foundation, March 2003
[8] OPC Fundamentals, Implementation, and Application, 3rd rev. Ed., Frank Iwanitz, Jürgen Lange, Printed in Germany, 2006, Hüthig GmbH
& Co. KG Heidelberg, ISBN 3-7785-2904-8
[9] www.S88.nl
[10] www.isa.org
How To Apply ISA 88
Dirk van der Linden
Scientific Researcher
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