This document provides standards for electrical schematic diagrams for the Large Hadron Collider project. It specifies requirements for diagram formatting, numbering schemes, file naming conventions, and archiving processes for high and low voltage distribution diagrams, relay and automation diagrams, lighting diagrams, and cooling/ventilation diagrams. The document aims to ensure a consistent and organized approach to creating and storing electrical schematics for the LHC.

1. LHC Project Document No.
LHC-PM-QA-403.00 rev 1.0
CERN Div./Group or Supplier/Contractor Document No.
-
EDMS Document No.
103568
Date: 2000-07-05
the
Large
Hadron
Collider
project
CERN
CH-1211 Geneva 23
Switzerland
Quality Assurance Standard
DESIGN STANDARDS
ELECTRICAL SCHEMATIC DIAGRAMS
Abstract
This document provides standards for all electrical schematic diagrams for the LHC and
its detectors. It covers:
! High and low voltage distribution diagrams.
! Relay and automatism diagrams.
! Lighting, power and earth protection diagrams.
! LHC main ring magnets cabling diagrams.
! Cooling and ventilation relay and automatism diagrams.
Prepared by :
Martial Dujardin
ST/EL
Martial.Dujardin@cern.ch
Joaquin Inigo-Golfin
ST/CV
Joaquin.Inigo-Golfin@cern.ch
Checked by :
LHC Quality Assurance
Working Group
Approved by :
Paul Faugeras
Deputy to LHC Project
Leader for Quality
Assurance

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History of Changes
Rev. No. Date Pages Description of Changes
0.1 draft
0.2 draft
1.0
2000-05-15
2000-05-24
2000-07-05 10
1st draft submitted to QAWG for comments
2nd draft submitted to QAWG for comments
References corrected. Released following QAWG meeting.

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Table of Contents
1. PURPOSE ............................................................................................. 4
2. POLICY ................................................................................................ 4
3. SCOPE.................................................................................................. 4
4. RESPONSIBILITIES .............................................................................. 4
5. DRAWING PREPARATION - GENERAL .................................................... 5
5.1 DRAWING SIZES .................................................................................. 5
5.2 TITLE BLOCK ....................................................................................... 5
5.3 MODIFICATION LIST ............................................................................. 6
6. NUMBERING SCHEMES ......................................................................... 6
6.1 DIAGRAMS PRODUCED BY ST/EL............................................................. 7
6.2 DIAGRAMS PRODUCED BY ST/CV ............................................................ 7
7. ARCHIVING PROCESS........................................................................... 7
7.1 ST/EL ELECTRICAL DIAGRAMS................................................................ 7
7.2 ST/CV ELECTRICAL DIAGRAMS ............................................................... 8
8. HIGH AND LOW VOLTAGE DISTRIBUTION UNIFILAR DIAGRAMS ........... 8
8.1 FILE NAMING CONVENTION.................................................................... 8
9. RELAY AND AUTOMATISM DIAGRAMS ................................................... 8
9.1 FILE NAMING CONVENTION.................................................................... 8
10. LIGHTING, POWER AND EARTH PROTECTION DIAGRAMS ...................... 9
10.1 FILE NAMING CONVENTION.................................................................... 9
11. LHC MAIN RING MAGNETS CABLING DIAGRAMS.................................... 9
12. COOLING AND VENTILATION RELAY AND AUTOMATISM DIAGRAMS .... 10
12.1 FILE NAMING CONVENTION...................................................................10
13. RELATED DOCUMENTATION ................................................................ 10
14. ANNEXES ........................................................................................... 10

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1. PURPOSE
To provide standards for all electrical schematic diagrams for the Large Hadron
Collider (LHC) and its detectors.
2. POLICY
All electrical schematic diagrams for the LHC project shall be created with a Computer
Aided Design (CAD) system, in accordance with the general quality assurance policy of
the LHC project.
The CAD systems used for electrical schematic diagrams prepared at CERN are
AutoCAD1
, the AutoCAD add-on application Alpage-Elec2
, and SEE 30002
.
All electrical schematic diagrams prepared at CERN, and referenced in a CERN
contractual document, shall incorporate the appropriate CERN title block. The drawing
tittle shall be written in English only or English and French.
All electrical schematics diagrams shall be stored in the CERN Drawing Directory
(CDD) with the relevant descriptive information and identified by a unique drawing
number defined in accordance with the CERN Drawing Directory rules as described in
the “CDD Manual”[ 1 ]. Diagrams may be stored as Hewlett Packard Graphic Language
(HPGL) plot files and native CAD files or as HPGL plot files only.
All electrical schematic diagrams shall be submitted to a review and approval process
before being released as described in "Drawing Management and Control", [ 2 ].
New versions of released diagrams shall be submitted to the same review and
approval process as the original diagrams.
3. SCOPE
This standard is applicable to:
All electrical schematic diagrams for the LHC and its detectors. This includes:
! High and low voltage distribution schematic diagrams.
! Relay, wiring and automatism schematic diagrams.
! Lighting, power and earth protection schematic diagrams.
! LHC main ring magnets cabling schematic diagrams.
! Cooling and ventilation relay and automatism diagrams.
4. RESPONSIBILITIES
Managers, Supervisors and Project Engineers (PE) at CERN working on the LHC Project
are responsible for:
! Ensuring that designers and draughtsman are aware of and understand the
procedures described in the present document.
! Ensuring that these design standards are fully implemented in their design.
–
1
AutoCAD is a registered trademark of Autodesk, Inc.
2
Alpage-Elec and SEE 3000 are registered trademarks of Ige-Xao

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! Ensuring that industrial support personnel assigned to CAD design and drafting
activity is suitably trained and has been informed of CERN practices before starting
work.
Every designer and draughtsman is responsible for producing diagrams in compliance
with these design standards.
The ST Division is responsible for the definition of equipment codes used for electrical
schematic diagrams. Equipment codes for LHC equipment have to be approved by the
LHC Co-ordinator for equipment codes [ 3 ].
The diagrams in the categories below are produced under the responsibility of the ST
Division Electrical Engineering and Telecom group (ST/EL).
! High and low voltage distribution schematic diagrams.
! Relay, wiring and automatism schematic diagrams.
! Lighting, power and earth protection schematic diagrams.
! LHC main ring magnets cabling schematic diagrams.
Cooling and ventilation relay and automatism diagrams are produced under the
responsibility of the ST Division Cooling and Ventilation group (ST/CV).
5. DRAWING PREPARATION - GENERAL
5.1 DRAWING SIZES
Unless otherwise specified all diagrams shall be made on one of the following
International Organization for Standardization (ISO) standard sizes:
Horizontal A0 (1189 x 841 mm)
A1 (841 x 594 mm)
A2 (594 x 420 mm)
A3 (420 x 297 mm)
Vertical A4 (297 x 210 mm)
5.2 TITLE BLOCK
Title blocks differ slightly depending on the CAD application used for preparing the
diagram, but they are in all cases compatible with CDD.
TITLE The diagram‘s title in English or in English and French
DRAWING NUMBER As described in chapter 6.
QA CATEGORY The code of the quality assurance category (1 char), see [ 4 ]
DRAWING SIZE The 2nd digit of the size (3 for size A3)
REVISION INDEX The 2nd letter of the revision index
AUTHOR The author’s initial and surname
DATE The date of creation of the drawing in ISO format (yyyy-mm-dd)
SCALE Used only for lighting, power and earth protection diagrams

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Figure 1 - Title block of a lighting diagram
Figure 2 - Title block of a single line diagram
5.3 MODIFICATION LIST
A new line has to be added to the modification list of diagrams for each revision, with
the following data:
INDEX The 2nd letter of the revision index.
DATE Date of the modification
NAME Initial and surname of the author of the modification
ZONE The location of the modification (1 char + 1 digit)
MODIFICATION The Engineering Change Request (ECR) number of the modification
or a text describing the modification(s)
Figure 3 - Diagram modification list
6. NUMBERING SCHEMES
The numbering scheme for electrical schematic diagrams is derived from the scheme
in use for LHC drawings. However deviations are introduced to take into account the
specific needs related to electrical diagrams.

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6.1 DIAGRAMS PRODUCED BY ST/EL
A deviation is introduced in the use of the sequential number which is 3 digits long
instead of 4. The digit freed in this way is used for a geographical location code. The
structure of the drawing number is:
Project code: A project identification code. For the LHC project the code is LHC
Equipment code: An LHC equipment code (5 chars/digits). See annex A1.
Zone A geographical location code (1 digit)
Number: A sequential number (3 digits).
Example:
PROJECT CODE EQUIPMENT CODE ZONE NUMBER
L H C E B L _ _ 5 0 1 4
Note: Equipment codes shorter than 5 chars/digits shall be completed with
underscores (_).
6.2 DIAGRAMS PRODUCED BY ST/CV
The position normally used for the equipment code is replaced by a 1 character
system code followed by a 4 digit building number. The structure of the drawing
number is:
Project code: A project identification code. For the LHC project the code is LHC
Sys: An LHC system identification code. E for electrical system.
Building A building number (4 digits).
Number: A sequential number (4 digits).
Example:
PROJECT CODE SYS BUILDING NUMBER
L H C E 2 6 8 4 0 0 0 1
7. ARCHIVING PROCESS
Electrical diagrams are archived in CDD as HPGL plot files. The process is described
below. Native CAD files of ST/CV diagrams are also stored in CDD.
7.1 ST/EL ELECTRICAL DIAGRAMS
A plot file in HPGL2 format is prepared and placed in a sub-directory of the directory
SRV4_DIVdrawingsDRAWINGSELECHPGL.
This sub-directory, and the plot file it contains, are named in accordance with the
following convention:
Sub-directory name DOPRJ
File name EQUIP3N.plt
where:

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DOPRJ: A design office code (2 digits) concatenated with a project code (3
chars)
EQUIP: The equipment code (5 chars/digits)
ZONE: The geographical location code (1 digit)
3N The second to fourth digits of the diagram sequential number-3
digits
Example:
The plot file of the drawing LHCEBL___5004 is named EBL5004.plt and stored in the
sub-directory SRV4_DIVdrawingsDRAWINGSELECHPGL77LHC.
Only the last version of the plot file is stored in this directory.
7.2 ST/CV ELECTRICAL DIAGRAMS
A plot file in HPGL2 format is prepared; it is named and stored following the
convention described in section 12.1 with the exception of the file extension which is
PLT instead of DWG.
8. HIGH AND LOW VOLTAGE DISTRIBUTION UNIFILAR
DIAGRAMS
High and low voltage distribution single line diagrams are prepared with the CAD
system Alpage Elec which will be replaced by SEE 3000 in the future. They are drawn
as a single folio in the sizes A0 to A4.
They shall be prepared in accordance to the to International Electrotechnical
Commission (IEC) 60364-1 (1992-10) standards, [ 5 ] and (IEC) 60617 standards,
[ 8 ], as well as to CERN Safety Instructions IS23 [ 6 ] and IS24 [ 7 ].
8.1 FILE NAMING CONVENTION
The native CAD files are stored on the NICE server SRV3_DIV, in the directory
ST_ELBEAE4_V4. A sub-directory is created for each diagram containing all the files
related to that diagram. This sub-directory is named in accordance with Alpage-Elec
constraints: 5 alphanumeric characters (1 letter followed by 4 digits)
Example: ST_ELBEAE4_V4M0002
9. RELAY AND AUTOMATISM DIAGRAMS
Relay and automatism schematic diagrams are prepared with the CAD systems Alpage
Elec and SEE 3000. Diagrams supplied by contractors may be prepared with AutoCAD.
They are drawn as multi-folios in A3 size.
They shall be prepared in accordance to the to International Electrotechnical
Commission (IEC) 60364-1 (1992-10) [ 5 ] and (IEC) 60617-1 (1985-01) [ 8 ]
standards, as well as to CERN Safety Instructions IS23 [ 6 ] and IS24 [ 7 ].
9.1 FILE NAMING CONVENTION
Alpage Elec: As described in chapter 6.1
SEE 3000: The native CAD files are stored on the NICE server SRV3_DIV, in
the directory ST_ELBESEE3000. A sub-directory is created for
each drawing containing all the files related to that drawing.

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Example: ST_ELBESEE300071LHCEM3001
10. LIGHTING, POWER AND EARTH PROTECTION DIAGRAMS
Lighting, power and earth protection schematic diagrams are combinations of an
electrical schematic diagram and an equipment installation layout.
They are prepared with AutoCAD. The parts list of equipment is prepared with the help
of a CERN developed AutoCAD application named ATT_TAB. This application is
described in the document “Etude et développement d’applications dans
l’environnement DAO AutoCAD pour l’aide à la gestion d’études électriques" written by
A. Croissant in 1992.
They shall be prepared in accordance to the International Electrotechnical Commission
(IEC) 60617 standards, [ 8 ], as well as to CERN Safety Instructions IS23, [ 6 ] and
IS24, [ 7 ].
The following rules shall be respected when preparing a drawing:
! The schematic part is drawn on the layer "SCHEMA".
! The installation layout part is drawn on the layer "IMP".
! They are drawn using the symbols library available on the NICE server
I:SRV4_DIVdrawingsDRAWINGSELECBE_LHCSTANDARDWB
10.1 FILE NAMING CONVENTION
The native CAD files are stored on the NICE server SRV4_DIVdrawings, in the
directory DRAWINGSELEC. A sub-directory is created for each set of diagrams. This
sub-directory, and the drawing files it contains, are named in accordance with the
following conventions:
Sub-directory name: DOPRJ
File name: EQUIPNUM.DWG
where:
DOPRJ: Design office code (2 digits) concatenated with a project code
(3chars)
EQUIP: Equipment code (5 chars/digits)
NUM: Geographical location code (1 digit) + sequential number (4 digits)
DWG Standard AutoCAD file extension
Example:
The file of the diagram LHCEBL__5004 is named EBL5004.DWG and is stored in the
directory I:SRV4_DIVdrawingsDRAWINGSELEC77LHC
11. LHC MAIN RING MAGNETS CABLING DIAGRAMS
These schematic diagrams are made with AutoCAD. They follow the standards
described in LHC-PM-QA-402.00 "Design Standards-Mechanical Engineering and
Installations" except for the pen sizes and colours.
They can only been printed on a colour plotter.

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12. COOLING AND VENTILATION RELAY AND AUTOMATISM
DIAGRAMS
Relay and automatism diagrams are prepared with the CAD systems ALPAGE ELEC and
SEE 3000 both in A3 and A4 sizes.
Diagrams supplied by contractors may be prepared with AutoCAD. They are drawn as
multi-folios in A3 size.
Diagrams shall be prepared in accordance to the International Electrotechnical
Commission (IEC) 60617 standards, [ 8 ].
12.1 FILE NAMING CONVENTION
The native CAD files are stored on the NICE server SRV4_DIVdrawings in the
directory DRAWINGSLHC. A sub-directory is created for each building, containing all
the files related to that building. This sub-directory is named according to the following
convention:
Sub-directory name EBLDG1N
File name EBLDG3N.DWG
where:
EBLDG: The character E followed by the building number(4 digits), total 5
digits
1N The first digit of the diagram sequential number-1 digit
3N The second to fourth digits of the diagram sequential number-3
digits
DWG The Standard AutoCAD and Alpage Elec file extension
Example:
The diagram numbered LHCE31820004 is stored in the directory:
SRV4_DIVdrawingsDRAWINGSLHCE31820E3182004.DWG
13. RELATED DOCUMENTATION
[ 1 ] CERN EST/98-01 (ISS) CDD Manual
[ 2 ] LHC-PM-QA-305.00 Drawing Management and Control
[ 3 ] LHC-PM-QA-204.00 Equipment Naming Conventions
[ 4 ] LHC-PM-QA-201.00 Quality Assurance Categories
[ 5 ] IEC 60364-1 (1992-10) Electrical installations of buildings
[ 6 ] TIS IS23 Criteria and standard test methods for the selection
of electric cables, wires and insulated parts with
respect to fire safety and radiation resistance
[ 7 ] TIS IS24 Regulations applicable to electrical installations
[ 8 ] IEC 60617 Graphical symbols for diagrams
14. ANNEXES
A.1 LHC equipment codes for AC electrical distribution
A.2 Example of an 18kV diagram
A.3 Example of a lighting schematic diagram
A.4 Example of a cooling and ventilation diagram

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EA : 400V, Assured by Diesel
EAC__: 400V, Assured by Diesel, controls & protections
EA___: 400V, Assured by Diesel, schematic diagram
EB : 400V, general services
EBC__: 400V, general services, controls & protections
EBF__: 400V, general services, powering
EBL__: 400V, general services, lighting
EB__: 400V, general services, schematic diagram
EC : <50V DC, controls and safety
ECC__:, <50V DC, controls and safety, crates
EC___:, <50V DC, controls and safety, schematic diagram
ED : reserve
EE : 20kV, supply from EDF
EEC__: 20kV, supply from EDF, controls & protections
EE___: 20kV, supply from EDF, schematic diagram
EF : 18kV Safety network
EFC__: 18kV Safety network, controls & protections
EF___: 18kV Safety network, schematic diagram
EG : 110V DC, Controls and safety
EGC__:, 110V DC, controls and safety, crates
EG___:, 110V DC, controls and safety, schematic diagram
EH : >66kV, high voltage
EHC__: >66kV, high voltage, controls & protections
EH___: >66kV, high voltage, schematic diagram & details
EI : Miscellaneous (Earth circuits, cable ladders)
EIE__: Earth circuits
EIW__: Cable ladders
EJ : >150V DC, battery circuits
EJ___: >150V DC, battery circuits
EK : 3.3 kV (& 6.3kV), normal network
EKC__: 3.3 kV, normal network, controls & protections
EK___: 3.3 kV, normal network, schematic diagram
EL : 3.3 kV, safety network
ELC__: 3.3 kV, safety network, controls & protections
EL___: 3.3 kV, safety network, schematic diagram
EM : 18kV, normal network
EMC__: 18kV, normal network, controls & protections
EM___: 18kV, normal network, schematic diagram
EN : Transducer circuits (temp probes, ...)
EN___: Transducer circuits
EO : 230 or 400V, supplied from UPS
EO___: 230 or 400V, supplied from UPS
EP : 230V, anti-panic lighting
EP___: 230V, anti-panic lighting
EQ : 400V, for cryogenics
EQ___: 400V, for cryogenics
ER : 400V , for power converters and machine
ER___: 400V, for power converters and machine
ES : 400V, safety network (not cut by emergency stop)
ES___: 400V, safety network (not cut by emergency stop)
ET : Remote Control
ET___: Remote control
EU : Emergency stop circuits
EU___: Emergency stop circuits
EV : 400V for vacuum equipment
EV___: 400V for vacuum equipment
EW : 400V for cooling and ventilation
EW___: 400V for cooling and ventilation
EX : 400V for experience
EX___: 400V for experience
EY : Equipment layout in buildings and structures
EY___: Equipment layout in buildings and structures
EZ : 400V for radio frequency
EZ___: 400V for radio frequency
Annex A.1: LHC equipment codes for AC electrical distribution

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Annex A.2: Example of an 18kV diagram

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Annex A.3: Example of a lighting schematic diagram

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A.4 Example of a cooling and ventilation diagram