Skip to content
Please enter a keyword to search
  • Preview

    I.S. HD 637:1999

    View superseded by
    Superseded A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
    View superseded by

    POWER INSTALLATIONS EXCEEDING 1 KV A.C.

    Available format(s):  Hardcopy, PDF

    Superseded date:  22-11-2010

    Language(s):  English

    Published date:  01-01-1999

    Publisher:  National Standards Authority of Ireland

    Add To Cart

    Table of Contents - (Show below) - (Hide below)

    FOREWORD
    1 SCOPE AND NORMATIVE REFERENCES
    2 DEFINITIONS
       2.1 GENERAL DEFINITIONS
       2.2 INSTALLATIONS
       2.3 TYPES OF INSTALLATIONS
       2.4 SAFETY MEASURES AGAINST ELECTRIC SHOCK
       2.5 CLEARANCES
       2.6 CONTROL AND PROTECTION
       2.7 EARTHING
    3 FUNDAMENTAL REQUIREMENTS
       3.1 ELECTRICAL REQUIREMENTS
            3.1.1 Methods of neutral earthing
            3.1.2 Voltage classification
            3.1.3 Current in normal operation
            3.1.4 Short circuit current
            3.1.5 Rated frequency
            3.1.6 Corona
       3.2 MECHANICAL REQUIREMENTS
            3.2.1 Tension load
            3.2.2 Erection load
            3.2.3 Ice load
            3.2.4 Wind load
            3.2.5 Switching forces
            3.2.6 Short-circuit forces
            3.2.7 Loss of conductor tension
            3.2.8 Vibration
            3.2.9 Dimensioning of supporting structures
       3.3 CLIMATIC AND ENVIRONMENTAL CONDITIONS
            3.3.1 Temperature
            3.3.2 Altitude and air pressure
            3.3.3 Humidity
            3.3.4 Precipitation
            3.3.5 Pollution
            3.3.6 Solar radiation
       3.4 SPECIAL REQUIREMENTS
            3.4.1 Installations at high altitudes
            3.4.2 Effects of small animals and microorganisms
            3.4.3 Noise level
            3.4.4 Effects of earthquakes
    4 INSULATION
       4.1 SELECTION OF INSULATION LEVEL
       4.2 VERIFICATION OF WITHSTAND VALUES
       4.3 MINIMUM CLEARANCES OF LIVE PARTS
       4.4 MINIMUM CLEARANCES BETWEEN PARTS UNDER SPECIAL
            CONDITIONS
       4.5 TESTED CONNECTION ZONES
    5 EQUIPMENT
       5.1 COMMON RULES
            5.1.1 General
            5.1.2 Installation
       5.2 SPECIFIC REQUIREMENTS
            5.2.1 Circuit-breakers, switch-disconnectors, fuses,
                   fuse-switch disconnectors, contactors,
                   disconnectors and earthing switches
            5.2.2 Power transformers and reactors
            5.2.3 Gas insulated metal-enclosed switchgear (GIS),
                   metal-enclosed switchgear, insulation-enclosed
                   switchgear and other prefabricated type-tested
                   switchgear assemblies
            5.2.4 Instrument transformers
            5.2.5 Surge arresters
            5.2.6 Capacitors
            5.2.7 Line traps
            5.2.8 Insulators
            5.2.9 Insulated cables
            5.2.10 Conductors and accessories
            5.2.11 Rotating machines
            5.2.12 Static converters
    6 INSTALLATIONS
       6.1 GENERAL REQUIREMENTS
            6.1.1 Circuit arrangement
            6.1.2 Documentation
            6.1.3 Transport routes
            6.1.4 Aisles and access areas
            6.1.5 Lighting
            6.1.6 Operational safety
            6.1.7 Labelling
       6.2 OPEN-TYPE OUTDOOR INSTALLATIONS
            6.2.1 Barrier clearances
            6.2.2 Obstacle clearances
            6.2.3 Boundary clearances
            6.2.4 Minimum height over access area
            6.2.5 Clearances to buildings
            6.2.6 External fences and access doors
       6.3 OPEN-TYPE INDOOR INSTALLATIONS
       6.4 INSTALLATION OF FACTORY-BUILT TYPE-TESTED
            ENCLOSED SWITCHGEAR
            6.4.1 General
            6.4.2 Additional requirements for gas-insulated
                   metal-enclosed switchgear
       6.5 REQUIREMENTS FOR BUILDINGS
            6.5.1 Introduction
            6.5.2 Structural provisions
            6.5.3 Rooms for switchgear
            6.5.4 Service areas
            6.5.5 Doors
            6.5.6 Draining of dielectric fluids
            6.5.7 Air conditioning and ventilation
            6.5.8 Building which require special consideration
       6.6 HIGH-VOLTAGE/LOW-VOLTAGE PREFABRICATED SUBSTATIONS
       6.7 MAST POLE AND TOWER INSTALLATIONS
    7 SAFETY MEASURES
       7.1 PROTECTION AGAINST DIRECT CONTACT
            7.1.1 General
            7.1.2 Measures for protection against direct
                   contact
            7.1.3 Protection requirements
       7.2 MEANS TO PROTECT PERSONS IN CASE OF INDIRECT CURRENT
       7.3 MEANS TO PROTECT PERSONS WORKING ON ELECTRICAL
            INSTALLATIONS
            7.3.1 Equipment for isolating installations or
                   apparatus
            7.3.2 Devices to prevent reclosing of isolating
                   devices
            7.3.3 Devices for determining the de-energized
                   state
            7.3.4 Devices for earthing and short-circuiting
            7.3.5 Equipment acting as barriers against
                   adjacent live parts
            7.3.6 Storage of accident prevention equipment
       7.4 PROTECTION FROM DANGERS RESULTING FROM ARC FAULT
       7.5 PROTECTION AGAINST DIRECT LIGHTNING STROKES
       7.6 PROTECTION AGAINST FIRE
            7.6.1 General
            7.6.2 Transformers, reactors
            7.6.3 Cables and flexible cords
            7.6.4 Other equipment with flammable liquid
       7.7 PROTECTION AGAINST LEAKAGE OF INSULATING LIQUID AND
            SF[6]
            7.7.1 Insulating liquid leakage and subsoil water
                   protection
            7.7.2 SF[6]-leakage (new SF[6])
            7.7.3 Failure with loss of SF[6] and its
                   decomposition products
       7.8 IDENTIFICATION AND MARKING
            7.8.1 General
            7.8.2 Information plates and warning plates
            7.8.3 Electrical hazard warning
            7.8.4 Installations with incorporated capacitors
            7.8.5 Emergency signs for emergency exits
    8 AUXILIARY INSTALLATIONS AND CONTROL SYSTEMS
       8.1 MONITORING AND CONTROL SYSTEMS
       8.2 DC AND AC SUPPLY CIRCUITS
            8.2.1 AC supply
            8.2.2 DC supply
       8.3 COMPRESSED AIR SYSTEMS
       8.4 SF[6] GAS HANDLING PLANTS
       8.5 BASIC RULES FOR ELECTO-MAGNETIC COMPATIBILITY OF
            CONTROL SYSTEMS
            8.5.1 Electrical noise sources in high voltage
                   installations
            8.5.2 Measures to be taken to reduce the effects
                   of high frequency interference
            8.5.3 Measures to be taken to reduce the effects
                   of low frequency interference
            8.5.4 Measures related to the selection of
                   equipment
            8.5.5 Other possible measures to reduce the
                   effects of interference
    9 EARTHING SYSTEMS
       9.1 PURPOSE
       9.2 DIMENSIONING OF EARTHING SYSTEMS AT POWER FREQUENCY
            9.2.1 General
            9.2.2 Dimensioning with respect to corrosion and
                   mechanical strength
            9.2.3 Dimensioning with respect to thermal strength
            9.2.4 Dimensioning with regard to touch and step
                   voltages
       9.3 CONSTRUCTION OF EARTHING SYSTEMS
            9.3.1 Installation of earth electrodes and
                   earthing conductors
            9.3.2 Measures to be taken to reduce the effects
                   of high frequency interference
            9.3.3 Transferred potentials
            9.3.4 Measures for earthing on equipment and
                   installations
       9.4 COMMON EARTHING SYSTEM FOR HIGH VOLTAGE AND LOW
            VOLTAGE SYSTEMS
            9.4.1 Conditions for a common earthing system
            9.4.2 Supply of low voltage installations inside
                   the area of a high voltage earthing system
            9.4.3 Supply of low voltage installations outside
                   the area of a high voltage earthing system
            9.4.4 Separated earthing systems
       9.5 EARTHING MEASURES AGAINST LIGHTNING EFFECTS
       9.6 MEASUREMENTS FOR AND ON EARTHING SYSTEMS
       9.7 SITE INSPECTION AND DOCUMENTATION OF EARTHING SYSTEMS
       9.8 GENERAL COMMENTS ON CHECKING AND SUPERVISION OF
            EARTHING SYSTEMS
            9.8.1 Checking by inspection
            9.8.2 Checking by measurement or calculation
    10 INSPECTION AND TESTING ON SITE BEFORE TAKING OVER
    ANNEX A (NORMATIVE) TYPE AND MINIMUM DIMENSIONS OF EARTH
            ELECTRODE MATERIALS ENSURING MECHANICAL STRENGTH
            AND CORROSION RESISTANCE
    ANNEX B (NORMATIVE) CURRENT RATING CALCULATION OF EARTHING
            CONDUCTORS AND EARTH ELECTRODES
    ANNEX C (NORMATIVE) TOUCH VOLTAGE AND BODY CURRENT
       C.1 EQUIVALENCE BETWEEN TOUCH VOLTAGE AND BODY CURRENT
       C.2 TAKING INTO ACCOUNT ADDITIONAL RESISTANCES
    ANNEX D (NORMATIVE) DESCRIPTION OF THE RECOGNIZED SPECIFIED
            MEASURES M
    ANNEX E (NORMATIVE) MEASURES ON EARTHING SYSTEMS TO REDUCE
            THE EFFECTS OF HIGH FREQUENCY INTERFERENCE
    ANNEX F (NORMATIVE) DETAILED MEASURES FOR EARTHING OF
            EQUIPMENT AND INSTALLATIONS
       F.1 FENCES AROUND SUBSTATION INSTALLATIONS
       F.2 PIPES
       F.3 TRACTION RAILS
       F.4 POLE MOUNTED TRANSFORMING AND/OR SWITCHING
            INSTALLATIONS
       F.5 SECONDARY CIRCUITS OF INSTRUMENT TRANSFORMERS
    ANNEX G (NORMATIVE) MEASURING TOUCH VOLTAGES
    ANNEX H (INFORMATIVE) METHODS OF PROTECTION AGAINST DIRECT
            LIGHTNING STROKES
       H.1 SHIELD WIRES
       H.2 LIGHTNING RODS
    ANNEX J (INFORMATIVE) REDUCTION FACTORS RELATED TO EARTH
            WIRES OF OVERHEAD LINES AND METAL SHEATHS OF
            UNDERGROUND CABLES
       J.1 GENERAL
       J.2 TYPICAL VALUES OF REDUCTION FACTORS OF OVERHEAD
            LINES AND CABLES (50 Hz)
    ANNEX K (INFORMATIVE) BASIS FOR THE DESIGN OF EARTHING
            SYSTEMS
       K.1 SOIL RESISTIVITY
       K.2 RESISTANCE TO EARTH
    ANNEX L (INFORMATIVE) INSTALLING THE EARTH ELECTRODES
            AND EARTHING CONDUCTORS
       L.1 INSTALLATION OF EARTH ELECTRODES
            L.1.1 Horizontal earth electrodes
            L.1.2 Vertical or inclined driven rods
            L.1.3 Jointing the earth electrodes
       L.2 INSTALLATION OF EARTHING CONDUCTORS
            L.2.1 Installing the earthing conductors
            L.2.2 Jointing the earthing conductors
    ANNEX M (INFORMATIVE) APPROXIMATE FORMULAE FOR SIMPLE
            EARTHING SYSTEMS: APPROPRIATE DISTANCES TO AVOID
            DANGEROUS VOLTAGES
    ANNEX N (INFORMATIVE) MEASUREMENTS FOR AND ON EARTHING
            SYSTEMS
       N.1 MEASUREMENT OF SOIL RESISTIVITIES
       N.2 MEASUREMENT OF RESISTANCES TO EARTH AND IMPEDANCES
            TO EARTH
       N.3 DETERMINATION OF THE EARTH POTENTIAL RISE
       N.4 ELIMINATION OF INTERFERENCE AND DISTURBANCE
            VOLTAGES FOR EARTHING MEASUREMENTS
    ANNEX P (INFORMATIVE) DETAILS ON SITE INSPECTION AND
            DOCUMENTATION OF EARTHING SYSTEMS
    ANNEX Q (INFORMATIVE) EXAMPLES FOR CHECKING THE CORRECT
            DESIGN CONCERNING THE PERMISSIBLE TOUCH VOLTAGE
    ANNEX R (INFORMATIVE) THE USE OF REINFORCING BARS IN
            CONCRETE FOR EARTHING PURPOSE
    ANNEX S (INFORMATIVE) A-DEVIATIONS
    A-DEVIATIONS FOR BELGIUM
    A-DEVIATIONS FOR SWITZERLAND
    A-DEVIATIONS FOR SPAIN
    A-DEVIATIONS FOR FINLAND
    A-DEVIATIONS FOR FRANCE
    A-DEVIATIONS FOR UNITED KINGDOM
    A-DEVIATIONS FOR ITALY
    A-DEVIATIONS FOR SWEDEN
    ANNEX T (NORMATIVE) SPECIAL NATIONAL CONDITIONS AND
            NATIONAL PROVISIONS (PART OF NATIONAL STANDARDS,
            SPECIFICATIONS OR PRACTICES)
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    CZECH REPUBLIC
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    DENMARK
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    FINLAND
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    FRANCE
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    UNITED KINGDOM
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    ITALY
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    THE NETHERLANDS
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    NORWAY
    SPECIAL NATIONAL CONDITIONS AND NATIONAL PROVISIONS FOR
    SWEDEN
    ANNEX U (INFORMATIVE) BIBLIOGRAPHY

    Abstract - (Show below) - (Hide below)

    Provides the requirements for the design and erection of electrical installations, in systems with nominal voltage above 1 kV a.c., so as to provide safety and proper functioning for the use intended.

    General Product Information - (Show below) - (Hide below)

    Document Type Standard
    Publisher National Standards Authority of Ireland
    Status Superseded
    Superseded By

    Standards Referencing This Book - (Show below) - (Hide below)

    EN 60517:1996/A11:1999 GAS-INSULATED METAL-ENCLOSED SWITCHGEAR FOR RATED VOLTAGES OF 72,5 KV AND ABOVE
    IEC 60826:2017 Design criteria of overhead transmission lines
    EN 60721-3-1:1997 Classification of environmental conditions - Part 3: Classification of groups of environmental parameters and their severities - Section 1: Storage
    HD 464 : S1 AMD 5 2002 DRY-TYPE POWER TRANSFORMERS
    IEC 60724:2000+AMD1:2008 CSV Short-circuit temperature limits of electric cables with rated voltages of 1 kV (Um = 1,2 kV) and 3 kV (Um = 3,6 kV)
    ISO 1996-2:2017 Acoustics — Description, measurement and assessment of environmental noise — Part 2: Determination of sound pressure levels
    EN 61219:1993 Live working - Earthing or earthing and short-circuiting equipment using lances as short-circuiting device - Lance earthing
    EN 60623:2017 Secondary cells and batteries containing alkaline or other non-acid electrolytes - Vented nickel-cadmium prismatic rechargeable single cells
    EN 50020:2002 Electrical apparatus for potentially explosive atmospheres - Intrinsic safety 'i'
    EN 61230:2008 LIVE WORKING - PORTABLE EQUIPMENT FOR EARTHING OR EARTHING AND SHORT-CIRCUITING
    EN 60721-3-9:1993/A1:1995 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - PART 3: CLASSIFICATION OF GROUPS OF ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES - SECTION 9: MICROCLIMATES INSIDE PRODUCTS
    EN 60721-3-5:1997 Classification of environmental conditions - Part 3: Classification of groups of environmental parameters and their severities - Section 5: Ground vehicle installations
    IEC 60478-1:1974 Stabilized power supplies, d.c. output. Part 1: Terms and definitions
    HD 606.1 : 200S1 MEASUREMENT OF SMOKE DENSITY OF ELECTRIC CABLES BURNING UNDER DEFINED CONDITIONS - TEST APPARATUS
    EN 60896-1:1991/A2:1992 STATIONARY LEAD-ACID BATTERIES - GENERAL REQUIREMENTS AND METHODS OF TEST - VENTED TYPES
    EN 60721-3-0:1993 Classification of environmental conditions - Part 3: Classification of groups of environmental parameters and their severities - Introduction
    IEC 61243-3:2014 Live working - Voltage detectors - Part 3: Two-pole low-voltage type
    IEC 60949:1988 Calculation of thermally permissible short-circuit currents, taking into account non-adiabatic heating effects
    EN 61100:1992 Classification of insulating liquids according to fire point and net calorific value
    IEC 61243-2:1995+AMD1:1999+AMD2:2002 CSV Live working - Voltage detectors - Part 2: Resistive type to be used for voltages of 1 kV to 36 kV a.c.
    EN 50017:1998 Electrical apparatus for potentially explosive atmospheres - Powder filling "q"
    EN 50019:2000/corrigendum Apr. 2003 ELECTRICAL APPARATUS FOR POTENTIALLY EXPLOSIVE ATMOSPHERES - INCREASED SAFETY "E"
    EN 60721-3-7:1995/A1:1997 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - PART 3: CLASSIFICATION OF GROUPS OF ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES - SECTION 7: PORTABLE AND NON-STATIONARY USE
    HD 606.2 : 200S1 MEASUREMENT OF SMOKE DENSITY OF ELECTRIC CABLES BURNING UNDER DEFINED CONDITIONS - TEST PROCEDURE AND REQUIREMENTS
    EN 50018 : 2000 AMD 1 2002 ELECTRICAL APPARATUS FOR POTENTIALLY EXPLOSIVE ATMOSPHERES - FLAMEPROOF ENCLOSURE "D"
    HD 472 S1:1989/AC:2013 NOMINAL VOLTAGES FOR LOW-VOLTAGE PUBLIC ELECTRICITY SUPPLY SYSTEMS
    EN 60255-6 : 94 AC 95 ELECTRICAL RELAYS - MEASURING RELAYS AND PROTECTION EQUIPMENT
    IEC 61243-1:2003+AMD1:2009 CSV Live working - Voltage detectors - Part 1: Capacitive type to be used for voltages exceeding 1 kV a.c.
    EN 60060-2:2011 High-voltage test techniques - Part 2: Measuring systems
    EN 60298:1996/A11:1999 A.C. METAL-ENCLOSED SWITCHGEAR AND CONTROLGEAR FOR RATED VOLTAGES ABOVE 1 KV AND UP TO AND INCLUDING 52 KV
    IEC 60044-6:1992 Instrument transformers - Part 6: Requirements for protective current transformers for transient performance
    EN 61330:1996 High-voltage/low-voltage prefabricated substations
    EN 60694:1996/A2:2001 COMMON SPECIFICATIONS FOR HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR STANDARDS
    ISO 1996-3:1987 Acoustics Description and measurement of environmental noise Part 3: Application to noise limits
    EN 50110-1:2013 Operation of electrical installations - Part 1: General requirements
    IEC 61243-5:1997 Live working - Voltage detectors - Part 5: Voltage detecting systems (VDS)
    ISO 1996-1:2016 Acoustics Description, measurement and assessment of environmental noise Part 1: Basic quantities and assessment procedures
    IEC 60478-2:1986 Stabilized power supplies, d.c. output. Part 2: Rating and performance
    EN 60865-1:2012 Short-circuit currents - Calculation of effects - Part 1: Definitions and calculation methods
    EN 60071-1:2006/A1:2010 INSULATION CO-ORDINATION - PART 1: DEFINITIONS, PRINCIPLES AND RULES
    EN 50265-2-2:1998 Common test methods for cables under fire conditions - Test for resistance to vertical flame propagation for a single insulated conductor or cable - Part 2-2: Procedures - Diffusion flame
    IEC 60287-3-1:2017 Electric cables - Calculation of the current rating - Part 3-1: Operating conditions - Site reference conditions
    EN 61082-1:2015 Preparation of documents used in electrotechnology - Part 1: Rules
    IEC 60478-5:1993 Stabilized power supplies, d.c. output - Part 5: Measurement of the magnetic component of the reactive near field
    EN 60071-2:1997 Insulation co-ordination - Part 2: Application guide
    ENV 61024-1 : DRAFT 1995 PROTECTION OF STRUCTURES AGAINST LIGHTNING - GENERAL PRINCIPLES
    EN 60622:2003 Secondary cells and batteries containing alkaline or other non-acid electrolytes - Sealed nickel-cadmium prismatic rechargeable single cells
    EN 50267-2-3:1998 Common test methods for cables under fire conditions - Tests on gases evolved during combustion of materials from cables - Part 2-3: Procedures - Determination of degree of acidity of gases for cables by determination of the weighted average of pH and conductivity
    IEC 60478-4:1976 Stabilized power supplies, d.c. output. Part 4: Tests other than radio-frequency interference
    EN 60721-1:1995/A2:1995 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - PART 1: ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES
    EN 50015:1998 Electrical apparatus for potentially explosive atmospheres - Oil immersion "o"
    EN 60721-3-2:1997 Classification of environmental conditions - Part 3: Classification of groups of environmental parameters and their severities - Section 2: Transportation
    HD 405.3 : 200S1 TESTS OF ELECTRIC CABLES UNDER FIRE CONDITIONS - TESTS ON BUNCHED WIRES OR CABLES
    EN 50016:2002 Electrical apparatus for potentially explosive atmospheres - Pressurized apparatus "p"
    HD 384.4.442 : 200S1 ELECTRICAL INSTALLATIONS OF BUILDINGS - PART 4: PROTECTION FOR SAFETY - CHAPTER 44: PROTECTION AGAINST OVERVOLTAGES - SECTION 442: PROTECTION OF LOW-VOLTAGE INSTALLATIONS AGAINST FAULTS BETWEEN HIGH-VOLTAGE SYSTEMS AND EARTH
    HD 384.3 : 200S2 ELECTRICAL INSTALLATIONS OF BUILDINGS - ASSESSMENT OF GENERAL CHARACTERISTICS
    EN 60076-2:2011 Power transformers - Part 2: Temperature rise for liquid-immersed transformers
    IEC 60331:1970 Fire-resisting characteristics of electric cables
    EN 50028:1987 Electrical apparatus for potentially explosive atmospheres - Encapsulation 'm'
    EN 60721-3-4:1995/A1:1997 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - PART 3: CLASSIFICATION OF GROUPS OF ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES - SECTION 4: STATIONARY USE AT NON-WEATHER-PROTECTED LOCATIONS
    EN 50014:1997/A2:1999 ELECTRICAL APPARATUS FOR POTENTIALLY EXPLOSIVE ATMOSPHERES - GENERAL REQUIREMENTS
    EN 50110-2:2010 Operation of electrical installations - Part 2: National annexes
    EN 60721-3-6:1993/A2:1997 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - PART 3: CLASSIFICATION OF GROUPS OF ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES - SHIP ENVIRONMENT
    EN 50265-1:1998 Common test methods for cables under fire conditions - Test for resistance to vertical flame propagation for a single insulated conductor or cable - Part 1: Apparatus
    IEC 60478-3:1989 Stabilized power supplies, d.c. output. Part 3: Reference levels and measurement of conducted electromagnetic interference (EMI)
    EN 60617-13:1993 Graphical symbols for diagrams - Part 13: Analogue elements
    HD 246.2 : 200S1 DIAGRAMS, CHARTS, TABLES - ITEM DESIGNATION
    EN 50265-2-1:1998 Common test methods for cables under fire conditions - Test for resistance to vertical flame propagation for a single insulated conductor or cable - Part 2-1: Procedures - 1 kW pre-mixed flame
    EN 60721-3-3 : 95 AMD 2 97 CLASSIFICATION OF ENVIRONMENTAL CONDITIONS - CLASSIFICATION OF GROUPS OF ENVIRONMENTAL PARAMETERS AND THEIR SEVERITIES - STATIONARY USE AT WEATHER-PROTECTED LOCATIONS
    HD 533 : 200S1 SHORT-CIRCUIT CALCULATION IN THREE-PHASE A.C. SYSTEMS
    View more information

    • Access your standards online with a subscription

      Features

      • Simple online access to standards, technical information and regulations
      • Critical updates of standards and customisable alerts and notifications
      • Multi - user online standards collection: secure, flexibile and cost effective