table of contents
table of contents............................................................................................................................ 4
1. Introduction............................................................................................................................. 5
1.1 PURPOSE of the
document........................................................................................ 5
1.2 SCOPE of the work....................................................................................................... 5
1.3 definitions, acronyms
and abbreviations....................................................... 6
1.4 references...................................................................................................................... 6
1.5 overview of the
document..................................................................................... 7
2. GENERAL DESCRIPTION.............................................................................................................. 7
2.1 product perspective.................................................................................................. 8
2.2 FUNCTION AND PURPOSE............................................................................................... 8
2.4 general constraints................................................................................................. 9
2.5 assumptions and
dependencies........................................................................... 10
This document
defines the user requirements for the NA58 Gas detection & monitoring
system.
This document
defines the User Requirements from a functional point of view, and not from a
technical point of view.
The main
objective of this document is to define clear and testable functions that can
be validated upon completion of the project.
All users shall
certify this document as being a faithful representation of their requirements
at the time of discussion.
This document
will be used by the ST-AA-AS section for the definition of the system
requirements and for the production of subsequent price inquiries to its
contractors for the supply and installation of gas detection equipment.
The objectives
of this work package is to extend the flammable, oxygen deficiency &
monitoring capabilities of the current gas detection & monitoring system
(based on a Labview program), to the NA58 experimental area.
The scope of the
work includes the introduction of a new gas distribution and test zone situated
in the experimental hall 888 including modifications to the existing Labview
applications by accessing data from installed PLC (a4dg888). New gas detection
infrastructure to include an air sampling system and oxygen deficiency will be
installed.
The work will be
based on the specifications of the existing gas detection and Labview program
developed by GTD / Spie Trindel.
AL3 Alarm-of-Level-3
CIE Control & Indication Equipment
GLIMOS Group Leader in Matters of Safety
HCI Human Computer Interface
PCR Prevessin Control Room
SCR Safety Control Room
SLIMOS Shift Leader in Matters of Safety
TCR Technical Control Room
TIM Technical Infrastructure Monitoring
TIS Technical Inspection and Safety commission
TOC Table Of Contents
URD User Requirements Document
XCR Experiment Control Room
Two classes of references are detailed in
this document:
·
Applicable documents are considered to
govern or form a part of this URD.
·
Reference documents have a bearing on
the content of the URD, but they do not govern or form a part of it.
[A1]
Software Engineering Standards, ESA
Board for Software Standardisation and Control, 1994.
[A2]
SL - ST - Software Repository. User
Documentation. Tool reference, Versions, Threads, and Issues.
[A3]
GTD documentation for the Gas control
system.
[A4]
Spie-Trindel documentation for the CIE
CGAZ-00128 (control & Indication Equipment).
[R1]
ESA PSS-05-02 Issue 1, Guide to the
User Requirements Definition Phase, October 1991.
The document is structured as follows:
Chapter 2 describes the general factors
that affect the system and its requirements. It does not state specific
requirements; it only makes those requirements easier to understand.
Chapter 3 describes & suggests further
recommendations to follow for some of the system requirements.
Appendix A Spreadsheet actions for a given alarm of level 2 & 3 for gas
distribution building 908.
Appendix B Spreadsheet actions for a given alarm of level 2 & 3 for the
gas mixing area building 888
Appendix C Spreadsheet actions for a given alarm of level 2 for the
Experimental zone building 888
Appendix D Spreadsheet actions for a given alarm of level 3 for the
Experimental zone building 888
Appendix E Spreadsheet actions for a given alarm of level 2 & 3 for the
RICH test zone building 888
Appendix F proposition "initial planning and responsibility
chart".
Appendix G Architecture of the proposed system.
Appendix H E719/MD-04 Access to gas application
EHN2.
2. GENERAL DESCRIPTION
There is a need to modify the existing gas
detection & monitoring system CGAZ-00128 installed in building 888 due to
the expansion of the experiments flammable and neutral gas needs.
The project has the following objectives:
·
Modify the remote gas monitoring
system for the NA58 experimental area.
·
Modify & install further hardware
components for the existing gas detection system CGAZ-00128 for the NA58
experimental area.
·
Execute the off-line testing of the
software for functional and performance validation
·
Execute on-line testing for
provisional acceptance
The
main functions of the gas detection & monitoring system CGAZ-00128 are to
include:
·
Surveillance of the flammable gas
distribution building 908 (via six catalytic flammable gas sensors)
·
Surveillance of the flammable and
neutral gas mixing zone situated within the experimental hall 888 (via four
catalytic flammable gas sensors)
·
Surveillance of the experimental area
(to include the Micro drift chambers, MW2 and the RICH experimental tent to
incorporate oxygen deficiency) located within the experimental hall 888 (via a
mixture of catalytic, air sampling and 02 deficiency).
·
Surveillance of the RICH chamber test
area located within the experimental hall 888.
·
Acquisition of the data from the
CIE (PLC included in the GAS
installation package) for alarm processing and transmission of these alarms to
the TCR & SCR respectively.
·
Display of the data on the HMI similar
to the existing Labview program developed by GTD.
The
system shall be an extension of the existing Gas monitoring system developed by
Spie-Trindel / GTD shown in the schematic diagram below.
Figure 1 –
Monitoring Architecture
.
The main constraints for the development
and implementation of such modifications can be considered as:
·
For the purpose of experimental
interlocks and slow control, the addition of a communications cable between the
CIE and the NA58 experimental control room is desired. (These signals are generated in the form of a dry contact (positive
security = opens when actioned).
·
RICH detectors require a constant
supply of clean gas to protect the CsI coated cathode(s), for this purpose
changes to the emergency shut down of the flammable & neutral gas supplies
are required.
·
Modifications to the relay logic for
the isolation of electrical supplies to individual experiments and flammable
gas zones when an alarm of level 3 is generated.
·
The installation & integration of
four additional catalytic heads to be placed inside the ventilation hoods
located in the gas mixing zone. These heads will also be interlocked and action
the 2 speed ventilation system to be installed by ST-CV. The new infrastructure
will be integrated into the existing Labview application by accessing the data
from the PLC a4dg888 and included in the GAS installation package.
·
The installation & integration of
one additional catalytic head and additional hardware for the RICH chamber
testing area. The new infrastructure
will be integrated into the existing Labview application by accessing the data
from the PLC a4dg888 and included in the GAS installation package.
·
The installation & integration of
a flammable gas air sampling system and an oxygen deficiency sensor to survey
the interior of the RICH tent. The
new infrastructure will be integrated into the existing Labview application by
accessing the data from the PLC a4dg888 and included in the GAS installation
package.
·
Interaction with the ventilation
system for a fault or alarm of level 3
·
The data should be read from a PLC
datablock structure agreed and documented with the GAS detection contractor
Spie-Trindel / GTD.
The special Freon gases,
which are supplied from gas building 908, are automatically cut along with the
flammable gases when an alarm of level 3 is generated. Special care should be
incorporated for the use of halogenated gases such as SF6 & R134a in the
presence of flammable gas catalytic sensors. Halogenates are poisonous to these
sensors reducing their life expectancy and effectiveness. It is recommended
that the existing sensors are replaced by anti poison reinforced catalytic
sensors and preventative maintenance is performed every 6 months.
The overall effectiveness
of the four flammable gas point detection sensors placed inside the ventilation
hood may be slightly reduced if placed within an environment of permanent
ventilation. ICARE recommend that the gas detection sensors action the
ventilation system to maximum speed and capacity only for a given alarm of
level three.
2.5
assumptions and dependencies
We do not consider that sabotage is a
likely event. No elaborate measures to prevent tampering with the monitoring
system will be taken. However, mechanisms of user authentication and password
protection shall be implemented to prevent manipulation by untrained or unauthorised
users.
The main assumption is that the
modifications to the CGAZ-00128 Gas detection & monitoring can be added to
the current gas monitoring application for the SPS experimental zones.
Abstract:[A2]
