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News from Stephan Gaertner
Articles:
ISA 18.1 - Annunciator Sequences
From your Standards Chairman, Stephan Gaertner
This 1979 standard is now open for review; comments to
be sent to Lois Ferson (lferson@isa.org), ISA Standards Coordinator.
In 1962, I was asked to design
a first-out alarm sequence, to identify which variable caused
a shutdown at an ammonia synthesis plant in Slovakia . I did
it with three relays (four for first-out points) and three
pilot lights: Green, red (for primary alarm) and yellow
for each point. When the primary alarm point's "red"
relay got activated, one of its contacts would disable
a bus to all the other red relays.
When annunciators
came along - first relay, then solid state type - they were
instantly popular. But what with DCS/PLC systems now? DCS's
have sophisticated alarm and historian software and displays
that make annunciators unnecessary. As for PLCs, unless they
are tied to an alarming HMI, they do not have the built-in
alarming sequences such as first-out, ringback, etc. Glen
Garfein and me once designed such a sequence for a furnace
shutdown system. It took up quite a few rungs.
Years
ago, I was asked by PG&E to design a "Black
Annunciator" for the Pittsburg power plant, using a combination
of existing local and central annunciators and Bailey DCS
logic. The idea was to eliminate nuisance alarms. I.e., if
a feedwater pump is on standby, do not alarm it's low lube
oil pressure. Also, there are often large numbers of defeated
(acknowledged) alarms left unnoticed or a sudden high number
of high priority alarms.
Today,
expert systems are being designed to support "Intelligent
Alarm Management", such as provided by Gensym or
Nexus Engineering . They assist the operator in taking corrective
action by analyzing the problem.
I.e., " Meta Alarms" reason about the status
of other alarms. System actions could range from a simple
advisory text message to paging or e-mailing to maintenance
or supervisory personnel to actually engage in a corrective
action sequence. Voice messages can allow the operator to
move around and still receive the “news”
See article in Control magazine, July 2003,“Alarm Rationalization”
Question to you readers:: Should there be a standard
design guide for alarm management in DCS? I.e., standardize
priority colors, visual and audible message formats,
nuisance suppression logic etc? Maybe tie to ISA
84.01 - "SIS for Process Control", which by
the way is now also open for review? Part of an HMI standard?
Send me your opinions.
And last: I have been the Norcal Standards Chairman for
umpteen years and would like very much to pass this function
on. Benefits: You become a Norcal ISA board member, with not
much work. You get to review (and print out) all new or renewed
standards and solicit comments from other members. Any
takers? Call me or any board member
Stephan
Gaertner
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Standards & Practices Update
2/1/2004
The following ISA Standards are available for review, either
as new standards or to re-confirm with or without amendments.
Any ISA member who wants to comment on these standards
during the review period should contact me for a copy.
• ISA 18.1-1979
Annunciator Sequences and Specifications;
respond by February
22, 2004
Note: Should probably be amended to include
DCS implementation
• ISA 82.0201
Safety Requirements for Electronic Instrumentation, part 2
• ISA 77.70 1994
Power Plant Instrument Piping
• ISA 840001,
Part 1,2,3 PLC’s in Safety Applications
Note: Very
Important!
• ISA 97.00.01,
-02 Vortex Flow Meters
• ISA 12.040.01
Draft 4 El. Equipment in Hazardous Locations
Stephan Gaetner’s e-mail address - stephang777@comcast.net
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The Art of Making a Good P&ID
October 2003
I reviewed a copy of the new S.5.7.01 P&ID standard.
It integrates the PIP (Process Industry Practices) standards
for presenting piping systems with the ISA functional symbols
for instrumentation and control. It also includes PIP Appendices
A-1, A-2 that show symbols for mechanical equipment (pumps,
compressors, heat exchangers etc.). There are also notes
such as: “Multi-staged compressors may be shown on multiple
P&IDs”.
If implemented, the cover sheets on the P&ID
stick files of all process type projects anywhere will now
have a uniform look. O.K., someone will always
add his own cherished items, i.e. a bucket steam trap.
Pipes vs. functionality:
I found that I&C engineers need to have a lot
of patience during P&ID reviews to listen to all the discussions
about drain valves. What about the process and control functions
of the system? How to present them in enough detail?
Write it in? But explanatory notes are frowned upon
for good reason:
A. Drawings get crowded
B. CAD is not
a text processor
C. Words can be ambiguous, symbols
are not.
After all, P&IDs are born out of the concept that a
picture is worth a thousand words.
Note: The ISA offers a CD : P&ID Clip Symbols, Version
2.0. I don’t know if it is updated for this S5.7 .01
version.
More on function:
There is an excellent article in CONTROL magazine, August
2002. So you did not have time to read it. That’s why I’ll
give you some hi-lights.
The article addresses in particular batch processes, to
be designed and documented in accordance with ISA S.88, but
it is valid for other processes too.
For such projects, the process engineer usually first writes
a Sequence of Operations document describing the process steps
shown on the diagrams.
The conceptual design then adds functional process
block diagrams, a version of process flow diagrams ( PFDs).
It lists only the major vessels and pieces of equipment (i.e.
a centrifuge).
Rather then using ISA symbols, important control steps
are explained using control or interlock notes and/or valve
sequencing matrix tables. ISA symbols do not address
timing, information management and operator interaction, nor
do they describe an organized approach to the software development
task.
Only then will a P&ID be derived to determine equipment
and piping required.
But approving these P&IDs for construction can be contentious,
as the functional and control strategies are not readily evident.
Therefore, the Functional Description (FS), with is flow
and logic diagrams, must become a critical part of the engineering
process; a deliverable no less important than drawings and
equipment specifications.
I did not see any reference to ISA SP 5.6.01: Functional
requirements for Documentation of Software Applications –
an excellent guide for i.e. presenting a step
sequence or a cause-and-consequence table..
As your S&P chairman, I could write to the SP
5.7 committee to add some statements to this regard into the
standard. Please give me your comments!
Stephan
Gaertner
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SP99 Manufacturing and Control Systems Security
We hope you found our previous Control Systems Security Conferences in September informative and useful.
Subsequent to the September NORCAL conferences, we have had an all day session in Chicago on October 21st, where experts from vendors, consultants, and the government, as well as industry users such as DuPont, discussed their current activities and future plans. On October 22 we held the first ISA Standards Committee meeting for SP99, Manufacturing and Control Systems Security. There were over 50 attendees in this meeting, and there are now over 100 participants in this standards activity.
The first work product from SP99 will be a set of three Technical Reports, intended to provide guidance to users in three key areas of Manufacturing and Control Systems Security:
* TR 99.00.01 - Available Technologies and how to apply them to control systems
* TR 99.00.02 - Development of control systems policies and procedures and what they should contain
* TR 99.00.03 - Auditing and Metrics
On January 14 in Palo Alto, we will review TR99.00.02, (I am chairing the working group writing TR 99.00.02), as well as the other activities underway. I will have handouts including the current annotated outline for TR99.00.02 (about 17 pages of information). Come to this local NORCAL meeting in Palo Alto, get updated on what has happened since September, and participate in developing a Technical Report!
I look forward to seeing you in Palo Alto.
The next formal meeting of ISA SP99 is in Houston on January 23 and 24th, after a two day conference on Control Systems Security. Find information on that meeting at ISA's web site, www.isa.org. Fees for the conference are $375, plus your expenses. The standards meeting is free, except for your time and expenses.
Note: The presentation materials from the Chicago October technical sessions, as well as the presentation materials from our local, (Alza and SMUD), September Conferences, are all available on ISA's web site at www.isa.org - Browse to Standards, Committees, ISA SP99, and look to the bottom of text information on the page (above the list of committee memebers), for the link to "A page of publicly available references which provide general background is also available by clicking here." or go directly to:
http://www.isa.org/Content/Microsites988/SP99,_Manufacturing_and_Control_Systems_Security1/
Home964/ISASP99PublicSecurityFilesIndex.doc
Thanks
Bob
Robert C. Webb
ISA SP99 Working Group 3 Chair
(510) 215-0236 (Office)
rwebb@powereng.com; rcw4@ix.netcom.com
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Standards for the Food and Pharmaceutical Industries
by Marge Widmeyer
A number of us in the NORCAL Section have been active participants in the development of standards and associated information over the years. All the way from fossil fired boiler controls to field bus and beyond. But there are many additional areas where ISA could provide the process and leadership, if you can provide the expertise, to write down industry practices and thus help industry as a whole to become more effective. We are not talking about giving away trade secrets here - but rather about documenting common consensus standards and practices so that all of us can spend less time on the routine and more time on the creative engineering needed to become leaders of any industry segment. Further, in many areas, standards are essential to allow effective communications and coordination, whether it be real time control information, or design details. Some industries have effectively developed a significant standards base in the instrumentation, systems and automation area, others are not as far along.
ISA is moving to assess and develop standards in the FPID area. An initial cut at the scope and purpose of S&P development for FPID is described below. Many of you, our NORCAL members, are involved in these industries. Should time be spent in other subject areas? Do we need to refocus this to higher priority activities? Would you like to participate? Please give me a call or drop me an email with your thoughts - I will get you connected with the appropriate FPID leadership - or email the Division Director, Marjorie Widmeyer, at mwidme@worldnet.att.net
Scope
To develop instrumentation standards for use in the Food and Pharmaceutical Industry, and to facilitate related activities, (for example, training and publications).
Purpose
The ISA Food and Pharmaceutical Industry Standards Committee is organized to be the focal point in ISA for documenting criteria, standards, practices, and procedures related to instrumentation and controls in food and pharmaceutical facilities. This documentation will normally take the form of ISA standards, recommended practices, technical reports, or other publications, such as books, and may be supplemented and supported by training where appropriate.
The purpose of this committee is to develop, maintain, and update standards, recommended practices, and technical reports related to the design, installation, maintenance, and use of measurement and control equipment and systems in food and pharmaceutical facilities.
Discussion and Initial Target Areas
The industries will benefit from development of standards representing user consensus on appropriate practices in several areas. Initially, the areas of validation and equipment specification are suggested. Validation: The FDA requires significant validation information for "medical devices". The FDA rules are general and not well known to people outside the Pharmaceutical industry. The same rules are currently applied to a wide range of medical devices, from sophisticated electronic instruments to sanitary napkins, (yes they are also considered medical devices). They also apply to a lot of packaging and process equipment made by organizations that are not always in the pharmaceutical industry. Standards or other documents describing the type of information the "device" builder should supply to support completing the validation file would be valuable to make the process easier. Security: With increasing connectivity to and use of global networks for management and control of everything from research to production and shipping, the potential for unintentional and intentional disruption of real time measurement and control systems is growing. A number of government and industry efforts are underway to minimize the danger to "critical infrastructure" and the possibility of significant economic loss. As in the integration of management information systems and control systems, there is a place for instrumentation, systems, and automation standards in this area to assure real time control functionality is maintained or enhanced as we add layers of protocol to enhance security. ISA is an effective forum to integrate the knowledge and expertise of the IT and controls community to create practical working solutions for this critical area. Safety Systems: ISA84, "Programmable Electronic System (PES) for Use in Safety Applications", has been a very active standard area. The committee and subcommittees have done an excellent job of developing consensus standards and all of the related information to understand and use them, to allow effective use of PLCs and other modern equipment in safety systems.
Their primary focus has been the chemical process industries. While specifically excluding nuclear safety from their scope, the work has been of such interest that the Nuclear Regulatory Commission has participated in ISA's 84 standards activities! Aspects of this standards area could be effectively adapted and adjusted to meet FPID needs, benefiting both the industry and regulatory bodies. (Note that ISA84 has been endorsed by OSHA as appropriate methodology to meet OSHA 1910 requirements). Equipment Specification: One of the most common requirements is a list of utilities required and their characteristics, unfortunately most suppliers do not provide accurate information in this area, for example, they will say a machine needs an electrical supply of 60 amps (sometimes without saying the voltage etc.) but when you look at the machine you see the main switch is 60 amps and when you measure the actual electrical consumption you find the machine consumes only 15 kW on an hourly basis and with the instantaneous values varying from 5 to 24 kW and so on. So a standard that defined the various components of utility requirements and how they should be reported as well as the units would help a lot. It would also help the design people and energy conservation people since the existing practices usually end up creating over designed facilities. Other areas for work would be documentation lists and what should be provided especially for computer systems. Then we get into the whole question of validation of computerized systems. By setting some standards we could help everybody to get what is needed.
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rev: 3/27/04 GJG
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