IEC Electrical-Installation Guide

This book, "Electrical Installation Guide according to IEC International Standards", which is compiled and printed in English by Schneider Electric, facilitates utilization of the IEC 60364 series of international standards concerned with safety, guarding, control, performance and protection of circuits, together with fundamentals and rules of electrical installation design. Moreover, the book contains topics of extreme importance that cover wide fields of electric power systems and their installations in different facilities. This renders the book a useful reference to each engineer and specialist in the field and an easy guide to such international standards and their application.

SASO, in recognition of the guide's important and comprehensive electric installation content, has translated it into Arabic to enable researchers and specialists to benefit from it in Arabic, if they desire.

In its capacity as the body entrusted with issuing and approving Saudi standards, SASO attaches particular importance to verification of safety in electrical installation in buildings. SASO is also acting assiduously to complete work on the national regulations of electrical installation based upon IEC 60364 series of international standards which are adopted as Saudi standards. In view of the divergence of the items of such standards and the many technical options offered, issuing an application guide to these standards is extremely useful. To this effect, the Saudi national regulations of electrical installation in buildings will be used. The guide being introduced here, will be an important reference for "the electrical installation guide according to Saudi standards" as part of the Saudi national regulations of electrical installation in buildings.

Dr. Khaled Y. Al-Khalaf

Vice Chairman, Board of Directors and Director General, SASO

A. contents

B. general - installed power

1. methodology

2. rules and statutory regulations

2.1 definition of voltage ranges

table B1

standard voltages between 100 V and 1000 V (IEC 38-1983) B3

table B2

standard voltages above 1 kV and not exceeding 35 kV (IEC 38-1983) B3

2.2 regulations

2.3 standards

2.4 quality and safety of an electrical installation

2.5 initial testing of an installation

2.6 periodic check-testing of an installation

table B3

frequency of check-tests commonly recommended for an electrical installation B6

2.7 conformity (with standards and specifications) of equipment

used in the installation

3. motor, heating and lighting loads

3.1 induction motors

table B4

power and current values for typical induction motors B9

3.2 direct-current motors

table B6

progressive starters with voltage ramp B10

table B7

progressive starters with current limitation B10

3.3 resistive-type heating appliances and incandescent lamps

(conventional or halogen)

table B8

current demands of resistive heating and incandescent lighting (conventional or halogen)

appliances B11

3.4 fluorescent lamps and related equipment

table B10

current demands and power consumption of commonly-dimensioned fluorescent

lighting tubes (at 220 V/240 V - 50 Hz) B12

table B11

current demands and power consumption of compact fluorescent lamps

(at 220 V/240 V - 50 Hz) B12

3.5 discharge lamps

table B12

current demands of discharge lamps B13

4. power loading of an installation

4.1 installed power (kW)

4.2 installed apparent power (kVA)

table B13

estimation of installed apparent power B15

4.3 estimation of actual maximum kVA demand

table B14

simultaneity factors in an apartment block B16

table B16

factor of simultaneity for distribution boards (IEC 439) B17

table B17

factor of simultaneity according to circuit function B17

4.4 example of application of factors ku and ks

table B18

an example in estimating the maximum predicted loading of an installation

A

B. general - installed power

4. power loading of an installation

4.5 diversity factor

4.6 choice of transformer rating

table B19

IEC-standardized kVA ratings of HV/LV 3-phase distribution transformers

and corresponding nominal full-load current values B18

4.7 choice of power-supply sources

C. HV/LV distribution substations

1. supply of power at high voltage

1.1 power-supply characteristics of high voltage distribution networks

table C1

relating nominal system voltages with corresponding rated system voltages

(r.m.s. values) C2

table C2

switchgear rated insulation levels C3

table C3A

transformers rated insulation levels in series I (based on current practice other than

in the United States of America and some other countries) C3

table C3B

transformers rated insulation levels in series II (based on current practice in the United

States of America and some other countries) C4

table C4

standard short-circuit current-breaking ratings extracted from table X IEC 56 C4

1.2 different HV service connections

1.3 some operational aspects of HV distribution networks

2. consumers HV substations

2.1 procedures for the establishment of a new substation

3. substation protection schemes

3.1 protection against electric shocks and overvoltages

3.2 electrical protection

table C18

power limits of transformers with a maximum primary current not exceeding 45 A C25 table C19

rated current (A) of HV fuses for transformer protection according to IEC 282-1 C26 table C20

3-phase short-circuit currents of typical distribution transformers C27

3.3 protection against thermal effects

3.4 interlocks and conditioned manœuvres

4. the consumer substation with LV metering

4.1 general

4.2 choice of panels

table C27

standard short-circuit MVA and current ratings at different levels of nominal voltage C37

4.3 choice of HV switchgear panel for a transformer circuit

4.4 choice of HV/LV transformer

table C31

categories of dielectric fluids C41

table C32

safety measures recommended in electrical installations using dielectric liquids

of classes 01, K1, K2 or K3 C42

5. a consumer substation with HV metering

5.1 general

5.2 choice of panels

D. low-voltage service connections

1. low-voltage public distribution networks

1.1 low-voltage consumers

table D1

survey of electricity supplies in various countries around the world. D1 table D2 D6

1.2 LV distribution networks

1.3 the consumer-service connection

1.4 quality of supply voltage

2. tariffs and metering

E. power factor improvement and harmonic filtering

1. power factor improvement

1.1 the nature of reactive energy

1.2 plant and appliances requiring reactive current

1.3 the power factor

1.4 tan

ϕ

1.5 practical measurement of power factor

1.6 practical values of power factor

table E5

example in the calculation of active and reactive power E4

table E7

values of cos ϕ and tan ϕ for commonly-used plant and equipment E4

2. why improve the power factor?

2.1 reduction in the cost of electricity

2.2 technical/economic optimization

table E8

multiplying factor for cable size as a function of cos ϕ E5

3. how to improve the power factor

3.1 theoretical principles

3.2 by using what equipment?

3.3 the choice between a fixed or automatically-regulated bank

of capacitors

4. where to install correction capacitors

4.1 global compensation

4.2 compensation by sector

4.3 individual compensation

7.1 transfert current and take-over current

7.2 types of faults involved in the transfer region

8. appendix 2␣ : ground-surface potential gradients

due to earth-fault currents

9. appendix 3␣ : vector diagram of ferro-resonance

A

E. power factor improvement and harmonic filtering

5. how to decide the optimum level of compensation

5.1 general method

5.2 simplified method

table E17

kvar to be installed per kW of load, to improve the power factor of an installation E12

5.3 method based on the avoidance of tariff penalties

5.4 method based on reduction of declared maximum apparent

power (kVA)

6. compensation at the terminals of a transformer

6.1 compensation to increase the available active power output

table E20

active-power capability of fully-loaded transformers, when supplying loads at different

values of power factor E14

6.2 compensation of reactive energy absorbed by the transformer

table E24

reactive power consumption of distribution transformers with 20 kV primary windings E16

7. compensation at the terminals of an induction motor

7.1 connection of a capacitor bank and protection settings

table E26

reduction factor for overcurrent protection after compensation E17

7.2 how self-excitation of an induction motor can be avoided

table E28

maximum kvar of P.F. correction applicable to motor terminals without risk

of self-excitation E19

8. example of an installation before and after

power-factor correction

9. the effect of harmonics on the rating of a capacitor

bank

9.1 problems arising from power-system harmonics

9.2 possible solutions

9.3 choosing the optimum solution

table E30

choice of solutions for limiting harmonics associated with a LV capacitor bank E22

9.4 possible effects of power-factor-correction capacitors

on the power-supply system

10. implementation of capacitor banks

10.1 capacitor elements

10.2 choice of protection, control devices, and connecting cables

11. appendix 1␣ : elementary harmonic filters

12. appendix 2␣ : harmonic suppression reactor

for a single (power factor correction)

capacitor bank

F. distribution within a low-voltage installation

1. general

assumed levels of transient overvoltage possible at different points of a typical

installation F8

table F12

typical levels of impulse withstand voltage of industrial circuit breakers labelled

Uimp = 8 kV F8

table F18

compatibility levels for installation materials F13

3. safety and emergency-services installations,

and standby power supplies

3.1 safety installations

3.2 standby reserve-power supplies

3.3 choice and characteristics of reserve-power supplies

table F21

table showing the choice of reserve-power supply types according to application

requirements and acceptable supply-interruption times F16

3.4 choice and characteristics of different sources

table F22

table of characteristics of different sources F17

3.5 local generating sets

4. earthing schemes

4.1 earthing connections

table F25

list of exposed-conductive-parts and extraneous-conductive-parts F20

4.2 definition of standardized earthing schemes

4.3 earthing schemes characteristics

4.4.1 choice criteria

4.4.2 comparison for each criterion

4.5 choice of earthing method - implementation

4.6 installation and measurements of earth electrodes

table F47

resistivity (Ω-m) for different kinds of terrain F33

table F48

mean values of resistivity (Ω-m) for an approximate estimation of an earth-electrode

resistance with respect to zero-potential earth F33

5. distribution boards

5.1 types of distribution board

5.2 the technologies of functional distribution boards

5.3 standards

5.4 centralized control

6. distributors

6.1 description and choice

6.2 conduits, conductors and cables

table F60

selection of wiring systems F41

table F61

erection of wiring systems F41

table F62

some examples of installation methods F43

table F63

designation code for conduits according to the most recent IEC publications F44 table F64

designation of conductors and cables according to CENELEC code for harmonized

cables F45

table F66

A

F. distribution within a low-voltage installation

7. external influences

7.1 classification

table F67

concise list of important external influences (taken from Appendix A of IEC 364-3) F48

7.2 protection by enclosures: IP code

G. protection against electric shocks

1. general

1.1 electric shock

1.2 direct and indirect contact

2. protection against direct contact

2.1 measures of protection against direct contact

2.2 additional measure of protection against direct contact

3. protection against indirect contact

3.1 measure of protection by automatic disconnection of the supply

table G8

maximum safe duration of the assumed values of touch voltage in conditions where

UL = 50 V G4

table G9

maximum safe duration of the assumed values of touch voltage in conditions where

UL = 25 V G4

3.2 automatic disconnection for a TT-earthed installation

table G11

maximum operating times of RCCBs (IEC 1008) G6

3.3 automatic disconnection for a TN-earthed installation

table G13

maximum disconnection times specified for TN earthing schemes (IEC 364-4-41) G7

3.4 automatic disconnection on a second earth fault in an IT-earthed

system

table G18

maximum disconnection times specified for an IT-earthed installation (IEC 364-4-41) G9

3.5 measures of protection against direct or indirect contact

without circuit disconnection

4. implementation of the TT system

4.1 protective measures

table G26

the upper limit of resistance for an installation earthing electrode which must not be

exceeded, for given sensitivity levels of RCDs at UL voltage limits of 50 V and 25 V G13

4.2 types of RCD

4.3 coordination of differential protective devices

5. implementation of the TN system

5.1 preliminary conditions

5.2 protection against indirect contact

table G42

correction factor to apply to the lengths given in tables G43 to G46 for TN systems G20 table G43

maximum circuit lengths for different sizes of conductor and

instantaneous-tripping-current settings for general-purpose circuit breakers G20 table G44

maximum circuit lengths for different sizes of conductor and rated currents for type B

circuit breakers G20

table G45

maximum circuit lengths for different conductor sizes and for rated currents of circuit

breakers of type C G21

6.2 protection against indirect contact

table G59

correction factors, for IT-earthed systems, to apply to the circuit lengths given

in tables G43 to G46 G28

6.3 high-sensitivity RCDs

6.4 in areas of high fire-risk

6.5 when the fault-current-loop impedance is particularly high

7. residual current differential devices (RCDs)

7.1 description

7.2 application of RCDs

table G70

electromagnetic compatibility withstand-level tests for RCDs G32 table G72

means of reducing the ratio I∆n/lph (max.) G33

7.3 choice of characteristics of a residual-current circuit breaker

(RCCB - IEC 1008)

table G74

typical manufacturers coordination table for RCCBs, circuit breakers, and fuses G34

H. the protection of circuits and the switchgear

H1. the protection of circuits

1. general

1.1 methodology and definitions

table H1-1

logigram for the selection of cable size and protective-device rating for a given circuit H1-1

1.2 overcurrent protection principles

1.3 practical values for a protection scheme

1.4 location of protective devices

table H1-7

general rules and exceptions concerning the location of protective devices H1-5

1.5 cables in parallel

1.6 worked example of cable calculations

table H1-9

calculations carried out with ECODIAL software (Merlin Gerin) H1-8 table H1-10

example of short-circuit current evaluation H1-9

2. practical method for determining the smallest

allowable cross-sectional-area of circuit conductors

2.1 general

table H1-11

logigram for the determination of minimum conductor size for a circuit H1-10

2.2 determination of conductor size for unburied circuits

table H1-12

code-letter reference, depending on type of conductor and method of installation H1-10 table H1-13

factor K1 according to method of circuit installation (for further examples refer

to IEC 364-5-52 table 52H) H1-11

table H1-14

correction factor K2 for a group of conductors in a single layer H1-11 table H1-15

correction factor K3 for ambient temperature other than 30 °C H1-12 table H1-17

case of an unburied circuit: determination of the minimum cable size (c.s.a.), derived

A

H. the protection of circuits and the switchgear

H1. the protection of circuits

2. practical method for determining the smallest

allowable cross-sectional-area of circuit conductors

2.3 determination of conductor size for buried circuits

table H1-19

correction factor K4 related to the method of installation H1-14 table H1-20

correction factor K5 for the grouping of several circuits in one layer H1-14 table H1-21

correction factor K6 for the nature of the soil H1-15

table H1-22

correction factor K7 for soil temperatures different than 20 °C H1-15 table H1-24

case of a buried circuit: minimum c.s.a. in terms of type of conductor; type of insulation;

and value of fictitious current I'z (I'z = Iz) H1-15

K

3. determination of voltage drop

3.1 maximum voltage-drop limit

table H1-26

maximum voltage-drop limits H1-17

3.2 calculation of voltage drops in steady load conditions

table H1-28

voltage-drop formulae H1-18

table H1-29

phase-to-phase voltage drop ∆U for a circuit, in volts per ampere per km H1-18

4. short-circuit current calculations

4.1 short-circuit current at the secondary terminals of a HV/LV

distribution transformer

table H1-32

typical values of Usc for different kVA ratings of transformers with HV windings i 20 kV H1-20 table H1-33

Isc at the LV terminals of 3-phase HV/LV transformers supplied from a HV system

with a 3-phase fault level of 500 MVA, or 250 MVA H1-20

4.2 3-phase short-circuit current (Isc) at any point within

a LV installation

table H1-36

the impedance of the HV network referred to the LV side of the HV/LV transformer H1-21 table H1-37

resistance, reactance and impedance values for typical distribution transformers

with HV windings i 20 kV H1-22

table H1-38

recapitulation table of impedances for different parts of a power-supply system H1-23 table H1-39

example of short-circuit current calculations for a LV installation supplied at 400 V

(nominal) from a 1,000 kVA HV/LV transformer H1-23

4.3 Isc at the receiving end of a feeder in terms of the Isc

at its sending end

table H1-40

Isc at a point downstream, in terms of a known upstream fault-current value

and the length and c.s.a. of the intervening conductors, in a 230/400 V 3-phase system H1-24

4.4 short-circuit current supplied by an alternator or an inverter

5. particular cases of short-circuit current

5.1 calculation of minimum levels of short-circuit current

table H1-49

maximum circuit lengths in metres for copper conductors (for aluminium, the lengths

must be multiplied by 0.62) H1-28

table H1-50

maximum length of copper-conductored circuits in metres protected by B-type

circuit breakers H1-29

6. protective earthing conductors (PE)

6.1 connection and choice

table H1-59

choice of protective conductors (PE) H1-33

6.2 conductor dimensioning

table H1-60

minimum c.s.a.'s for PE conductors and earthing conductors

(to the installation earth electrode) H1-34

table H1-61

k factor values for LV PE conductors, commonly used in national standards

and complying with IEC 724 H1-34

6.3 protective conductor between the HV/LV transformer

and the main general distribution board (MGDB)

table H1-63

c.s.a. of PE conductor between the HV/LV transformer and the MGDB, in terms of transformer

ratings and fault-clearance times used in France H1-35

6.4 equipotential conductor

7. the neutral conductor

7.1 dimensioning the neutral conductor

7.2 protection of the neutral conductor

table H1-65

table of protection schemes for neutral conductors in different earthing systems H1-37

H2. the switchgear

1. the basic functions of LV switchgear

table H2-1

basic functions of LV switchgear H2-1

1.1 electrical protection

1.2 isolation

table H2-2

peak value of impulse voltage according to normal service voltage of test specimen H2-2

1.3 switchgear control

2. the switchgear and fusegear

2.1 elementary switching devices

table H2-7

utilization categories of LV a.c. switches according to IEC 947-3 H2-5 table H2-8

factor "n" used for peak-to-rms value (IEC 947-part 1) H2-5 table H2-13

zones of fusing and non-fusing for LV types gG and gM class fuses

(IEC 269-1 and 269-2-1) H2-7

2.2 combined switchgear elements

3. choice of switchgear

3.1 tabulated functional capabilities

table H2-19

functions fulfilled by different items of switchgear H2-11

A

H2. the switchgear

4. circuit breakers

table H2-20

functions performed by a circuit breaker/disconnector H2-12

4.1 standards and descriptions

4.2 fundamental characteristics of a circuit breaker

table H2-28

tripping-current ranges of overload and short-circuit protective devices

for LV circuit breakers H2-16

table H2-31

Icu related to power factor (cos ϕ) of fault-current circuit (IEC 947-2) H2-17

4.3 other characteristics of a circuit breaker

table H2-34

relation between rated breaking capacity Icu and rated making capacity Icm at different power-factor values of short-circuit current, as standardized in IEC 947-2 H2-19

4.4 selection of a circuit breaker

table H2-38

examples of tables for the determination of derating/uprating factors to apply to CBs

with uncompensated thermal tripping units, according to temperature H2-21 table H2-40

different tripping units, instantaneous or short-time delayed H2-23 table H2-43

maximum values of short-circuit current to be interrupted by main and principal

circuit breakers (CBM and CBP respectively), for several transformers in parallel H2-25

4.5 coordination between circuit breakers

table H2-45

example of cascading possibilities on a 230/400 V or 240/415 V 3-phase installation H2-28 table H2-49

summary of methods and components used in order to achieve discriminative tripping H2-29

4.6 discrimination HV/LV in a consumer's substation

J. particular supply sources and loads

1. protection of circuits supplied by an alternator

1.1 an alternator on short-circuit

1.2 protection of essential services circuits supplied in emergencies

from an alternator

1.3 choice of tripping units

1.4 methods of approximate calculation

table J1-7

procedure for the calculation of 3-phase short-circuit current J6 table J1-8

procedure for the calculation of 1-phase to neutral short-circuit current J7

1.5 the protection of standby and mobile a.c. generating sets

2. inverters and UPS

(Uninterruptible Power Supply units)

2.1 what is an inverter?

2.2 types of UPS system

table J2-4

examples of different possibilities and applications of inverters, in decontamination of supplies

and in UPS schemes J11

2.3 standards

2.4 choice of a UPS system

2.5 UPS systems and their environment

currents and c.s.a. of copper-cored cables feeding the rectifier, and supplying the load

for UPS system Maxipac (cable lengths < 100 m) J21

table J2-23

currents and c.s.a. of copper-cored cables feeding the rectifier, and supplying the load for UPS system EPS 2000 (cable lengths < 100 m). Battery cable data are also included J21 table J2-24

input, output and battery currents for UPS system EPS 5000 (Merlin Gerin) J22

2.9 choice of protection schemes

2.10 complementary equipments

3. protection of LV/LV transformers

3.1

transformer-energizing in-rush current

3.2 protection for the supply circuit of a LV/LV transformer

3.3 typical electrical characteristics of LV/LV 50 Hz transformers

table J3-5

typical electrical characteristics of LV/LV 50 Hz transformers J26

3.4 protection of transformers with characteristics as tabled in J3-5

above, using Merlin Gerin circuit breakers

table J3-6

protection of 3-phase LV/LV transformers with 400 V primary windings J26 table J3-7

protection of 3-phase LV/LV transformers with 230 V primary windings J27 table J3-8

protection of 1-phase LV/LV transformers with 400 V primary windings J27 table J3-9

protection of 1-phase LV/LV transformers with 230 V primary windings J28

4. lighting circuits

4.1 service continuity

4.2 lamps and accessories (luminaires)

table J4-1

analysis of disturbances in fluorescent-lighting circuits J30

4.3 the circuit and its protection

4.4 determination of the rated current of the circuit breaker

table J4-2

protective circuit breaker ratings for incandescent lamps and resistive-type heating

circuits J31

table J4-3

maximum limit of rated current per outgoing lighting circuit, for high-pressure discharge

lamps J32

table J4-4

current ratings of circuit breakers related to the number of fluorescent luminaires to be

protected J32

4.5 choice of control-switching devices

table J4-5

types of remote control J33

4.6 protection of ELV lighting circuits

4.7 supply sources for emergency lighting

5. asynchronous motors

5.1 protective and control functions required

table J5-2

commonly-used types of LV motor-supply circuits J37

5.2 standards

5.3 basic protection schemes: circuit breaker / contactor / thermal relay

table J5-4

A

J. particular supply sources and loads

5. asynchronous motors

5.5 maximum rating of motors installed for consumers supplied at LV

table J5-12

maximum permitted values of starting current for direct-on-line LV motors (230/400 V) J43 table J5-13

maximum permitted power ratings for LV direct-on-line-starting motors J43

5.6 reactive-energy compensation (power-factor correction)

6. protection of direct-current installations

6.1 short-circuit currents

6.2 characteristics of faults due to insulation failure, and of protective

switchgear

table J6-4

characteristics of protective switchgear according to type of d.c. system earthing J45

6.3 choice of protective device

table J6-5

choice of d.c. circuit breakers manufactured by Merlin Gerin J46

6.4 examples

6.5 protection of persons

7. Appendix␣ : Short-circuit characteristics

of an alternator

L. domestic and similar premises and special locations

1. domestic and similar premises

1.1 general

1.2 distribution-board components

1.3 protection of persons

1.4 circuits

table L1-9

recommended minimum number of lighting and power points in domestic premises L6 table L1-11

c.s.a. of conductors and current rating of the protective devices in domestic

installations (the c.s.a. of aluminium conductors are shown in brackets) L7

2. bathrooms and showers

2.1 classification of zones

2.2 equipotential bonding

2.3 requirements prescribed for each zone

3. recommendations applicable to special installations

the study of an electrical installation

by means of this guide requires the

reading of the entire text in the order

in which the chapters are presented.

listing of power demands

The study of a proposed electrical installation necessitates an adequate understanding of all governing rules and regulations. A knowledge of the operating modes of power-consuming appliances, i.e. "loads" (steady-state demand, starting conditions, non-simultaneous operation, etc.) together with the location and magnitude of each load shown on a building plan, allow a listing of power demands to be compiled. The list will include the total power of the loads installed as well as an estimation of the actual loads to be supplied, as deduced from the operating modes.

From these data the power required from the supply source and (where appropriate) the number of sources necessary for an adequate supply to the installation, are readily obtained.

Local information regarding tariff structures is also required to permit the best choice of connection arrangement to the power-supply network, e.g. at high voltage or low voltage.

corresponding chapter

B - general - installed power

service connection

This connection can be made at: c High Voltage:

a consumer-type substation will then have to be studied, built and equipped. This substation may be an outdoor or indoor installation conforming to relevant standards and regulations (the low-voltage section may be studied separately if necessary). Metering at high-voltage or low-voltage is possible in this case

c Low Voltage:

the installation will be connected to the local power network and will (necessarily) be metered according to LV tariffs.

C - HV/LV distribution substations

D - low-voltage service connections

reactive energy

The compensation of reactive energy within electrical installations normally concerns only power factor improvement, and is carried out locally, globally or as a combination of both methods.

E - power factor improvement

LV distribution

The whole of the installation distribution network is studied as a complete system. The number and characteristics of standby emergency-supply sources are defined. Earth-bonding connections and neutral-earthing arrangements are chosen according to local regulations, constraints related to the power-supply, and to the nature of the installation loads.

The hardware components of distribution, together with distribution boards and cableways, are determined from building plans and from the location and grouping of loads.

The kinds of location, and activities practised in them, can affect their level of resistance to external influences.

F - distribution within a low-voltage installation

protection against electric shock

The system of earthing (TT, IT or TN) having been previously determined, it remains, in order to achieve protection of persons against the hazards of direct and indirect contact, to choose an appropriate scheme of protection.

B

circuits and switchgear

Each circuit is then studied in detail.

From the rated currents of the loads; the level of short-circuit current; and the type of protective device, the cross-sectional area of circuit conductors can be determined, taking into account the nature of the cableways and their influence on the current rating of conductors.

Before adopting the conductor size indicated above, the following requirements must be satisfied:

c the voltage drop complies with the relevant standard,

c motor starting is satisfactory,

c protection against electric shock is assured. The short-circuit current Isc is then

determined, and the Isc thermal and electro-dynamic withstand capability of the circuit is checked.

These calculations may indicate that a different conductor size than that originally chosen is necessary.

The performance required by the switchgear will determine its type and characteristics. The use of cascading techniques and the discriminative operation of fuses and tripping of circuit breakers are examined.

H1 - the protection of circuits

H2 - the switchgear

particular supply sources

and loads

Particular items of plant and equipment are studied:

c specific sources such as alternators or inverters,

c specific loads with special characteristics, such as induction motors, lighting circuits or LV/LV transformers, or

c specific systems, such as direct-current networks.

J - particular supply sources and loads

domestic and similar premises

and special locations

Certain premises and locations are subject to particularly strict regulations: the most common example being domestic dwellings.

L - domestic and similar premises and special locations

Ecodial 2.2 software

Ecodial 2.2 software* provides a complete conception and design package for LV installations, in accordance with IEC standards and recommendations.

The following features are included: c construction of one-line diagrams, c calculation of short-circuit currents, c calculation of voltage drops, c optimization of cable sizes,

c required ratings of switchgear and fusegear, c discrimination of protective devices, c recommendations for cascading schemes, c verification of the protection of persons,

c comprehensive print-out of the foregoing calculated design data.

three phase, four wire or three wire systems single phase, three wire systems nominal voltage (V) nominal voltage (V)

- 120/240

230/400(1)

-277/480(2)

-400/690(1)

-1000

-Low-voltage installations are governed by a number of regulatory and advisory texts, which may be classified as follows:

c statutory regulations (decrees, factory acts, etc.),

c codes of practice, regulations issued by professional institutions, job specifications, c national and international standards for installations,

c national and international standards for products.

2.1 definition of voltage ranges

IEC voltage standards and

recommendations

table B1: standard voltages between 100 V and 1000 V (IEC 38-1983).

1) The nominal voltage of existing 220/380 V and 240/415 V systems shall evolve towards the recommended value of 230/400 V. The transition period should be as short as possible, and should not exceed 20 years after the issue of this IEC publication. During this period, as a first step, the electricity supply authorities of countries having 220/380 V systems should bring the voltage within the range 230/400 V +6% -10% and those of countries having 240/415 V systems should bring the voltage within the range 230/400 V +10% -6%. At the end of this transition period the tolerance of 230/400 V ±10% should have been achieved; after this the reduction of this range will be considered. All the above considerations apply also to the present 380/660 V value with respect to the recommended value 400/690 V.

2) Not to be utilized together with 230/400 V or 400/690 V.

50 Hz and 60 Hz systems 60 Hz systems

series I series II (North American practice) highest voltage nominal system highest voltage nominal system for equipment (kV) voltage (kV) for equipment (kV) voltage (kV)

3.6(1) _3.3(1) ₃₍(1) _4.40(1) _4.16(1) 7.2(1) _6.6(1) ₆(1) _- -12 11 10 - -- - - 13.2(2) _12.47(2) - - - 13.97(2) _13.2(2) - - - 14.52(1) _13.8(1) (17.5) - (15) - -24 22 20 - -- - - 26.4(2) _24.94(2) 36(3) ₃₃(3) _{- -} -- - - 36.5(2) _34.5(2) 40.5(3) _{- 35}(3) _-

-table B2: standard voltages above 1 kV and not exceeding 35 kV (IEC 38-1983).

* These systems are generally three-wire systems unless otherwise indicated. The values indicated are voltages between phases.

The values indicated in parentheses should be considered as non-preferred values. It is recommended that these values should not be used for new systems to be constructed in future.

1) These values should not be used for public distribution systems. 2) These systems are generally four-wire systems.

B

2.2 regulations

In most countries, electrical installations shall comply with more than one set of regulations, issued by National Authorities or by

recognised private bodies. It is essential to take into account these local constraints before starting the design.

2.3 standards

This Guide is based on relevant IEC standards, in particular IEC 364. IEC 364 has been established by medical and engineering experts of all countries in the world

comparing their experience at an international level. Currently, the safety principles of IEC 364 and 479-1 are the fundamentals of most electrical standards in the world. IEC - 38 Standard voltages

IEC - 56 High-voltage alternating-current circuit breakers IEC - 76-2 Power transformer - Part 2: Temperature rise

IEC - 76-3 Power transformer - Part 3: Insulation levels and dielectric tests IEC - 129 Alternating current disconnectors and earthing switches IEC - 146 General requirements and line commutated converters

IEC - 146-4 General requirements and line commutated converters - Part 4: Method of specifying the performance and test requirements of uninterruptible power systems

IEC - 265-1 High-voltage switches - Part 1: High-voltage switches for rated voltages above 1 kV and less than 52 kV

IEC - 269-1 Low-voltage fuses - Part 1: General requirements

IEC - 269-3 Low-voltage fuses - Part 3: Supplementary requirements for fuses for use by unskilled persons (fuses mainly for household and similar applications) IEC - 282-1 High-voltage fuses - Part 1: Current limiting fuses

IEC - 287 Calculation of the continuous current rating of cables (100% load factor) IEC - 298 AC metal-enclosed switchgear and controlgear for rated voltages above 1kV

and up to and including 52 kV IEC - 364 Electrical installations of buildings

IEC - 364-3 Electrical installations of buildings - Part 3: Assessment of general characteristics

IEC - 364-4-41 Electrical installations of buildings - Part 4: Protection of safety - Section 41: Protection against electrical shock

IEC - 364-4-42 Electrical installations of buildings - Part 4: Protection of safety - Section 42: Protection against thermal effects

IEC - 364-4-43 Electrical installations of buildings - Part 4: Protection of safety - Section 43: Protection against overcurrent

IEC - 364-4-47 Electrical installations of buildings - Part 4: Application of protective measures for safety - Section 47: Measures of protection against electrical shock IEC - 364-5-51 Electrical installations of buildings - Part 5: Selection and erection of electrical

equipment - Section 51: Common rules

IEC - 364-5-52 Electrical installations of buildings - Part 5: Selection and erection of electrical equipment - Section 52: Wiring systems

IEC - 364-5-53 Electrical installations of buildings - Part 5: Selection and erection of electrical equipment - Section 53: Switchgear and controlgear

IEC - 364-6 Electrical installations of buildings - Part 6: Verification

IEC - 364-7-701 Electrical installations of buildings - Part 7: Requirements for special installations or locations - Section 701: Electrical installations in bathrooms IEC - 364-7-706 Electrical installations of buildings - Part 7: Requirements for special

installations or locations - Section 706: Restrictive conductive locations IEC - 364-7-710 Electrical installations of buildings - Part 7: Requirements for special

installations or locations - Section 710: Installation in exhibitions, shows, stands and funfairs

IEC - 420 High-voltage alternating current switch-fuse combinations

IEC - 439-1 Low-voltage switchgear and controlgear assemblies - Part 1: Types-tested and partially type-tested assemblies

IEC - 439-2 Low-voltage switchgear and controlgear assemblies - Part 2: Particular requirements for busbar trunking systems (busways)

IEC - 439-3 Low-voltage switchgear and controlgear assemblies - Part 3: Particular requirements for low-voltage switchgear and controlgear assemblies intended to be installed in places where unskilled persons have access for their use -Distribution boards

2.4 quality and safety of an electrical installation

Only by

c the initial checking of the conformity of the electrical installation,

c the verification of the conformity of electrical equipment,

c and periodic checking

can the permanent safety of persons and security of supply to equipment be achieved.

IEC - 787 Application guide for selection for fuse-links of high-voltage fuses for transformer circuit application

IEC - 831-1 Shunt power capacitors of the self-healing type for a.c. systems having a rated voltage up to and including 660 V. - Part 1: General - Performance, testing and rating - Safety requirements - Guide for installation and operation

B

2.6 periodic check-testing of an installation

In many countries, all industrial and commercial-building installations, together with installations in buildings used for public gatherings, must be re-tested periodically by authorized agents.

Table B3 shows the frequency of testing commonly prescribed according to the kind of installation concerned.

installations which require c locations at which a risk of degradation, annually

the protection of employees fire or explosion exists

c temporary installations at worksites c locations at which HV installations exist c restrictive conducting locations where mobile equipment is used

other cases every 3 years

installations in buildings according to the type of establishment

used for public gatherings, and its capacity for receiving the public,

2.5 initial testing of an installation

Before a power-supply authority will connect an installation to its supply network, strict pre-commissioning electrical tests and visual inspections by the authority, or by its appointed agent, must be satisfied. These tests are made according to local (governmental and/or institutional)

regulations, which may differ slightly from one country to another. The principles of all such regulations however, are common, and are based on the observance of rigorous safety rules in the design and realization of the installation.

IEC 364 and related standards included in this guide are based on an international consensus for such tests, intended to cover all the safety measures and approved installation practices normally required for domestic, commercial and (the majority of) industrial buildings. Many industries however have additional regulations related to a particular product (petroleum, coal, natural gas, etc.). Such additional requirements are beyond the scope of this guide.

The pre-commissioning electrical tests and visual-inspection checks for installations in buildings include, typically, all of the following: c insulation tests of all cable and wiring conductors of the fixed installation, between phases and between phases and earth, c continuity and conductivity tests of protective, equipotential and earth-bonding conductors,

c resistance tests of earthing electrodes with respect to remote earth,

c allowable number of socket-outlets per circuit check,

c cross-sectional-area check of all conductors for adequacy at the short-circuit levels prevailing, taking account of the associated protective devices, materials and installation conditions (in air, conduit, etc.), c verification that all exposed- and extraneous metallic parts are properly earthed (where appropriate),

c check of clearance distances in bathrooms, etc.

These tests and checks are basic (but not exhaustive) to the majority of installations, while numerous other tests and rules are included in the regulations to cover particular cases, for example: TN-, TT- or IT-earthed installations, installations based on class 2 insulation, SELV circuits, and special locations, etc.

The aim of this guide is to draw attention to the particular features of different types of installation, and to indicate the essential rules to be observed in order to achieve a satisfactory level of quality, which will ensure safe and trouble-free performance. The methods recommended in this guide, modified if necessary to comply with any possible variation imposed by a local supply authority, are intended to satisfy all pre-commissioning test and inspection requirements.

c

the standards organization concerned, or c by a certificate of conformity issued by a laboratory, or

c by a declaration of conformity from the manufacturer.

declaration of conformity

In cases where the equipment in question is to be used by qualified or experienced persons, the declaration of conformity provided by the manufacturer (included in the technical documentation) together with a conformity mark on the equipment concerned, are generally recognized as a valid attestation. Where the competence of the manufacturer is in doubt, a certificate of conformity can be obtained from an independent accredited laboratory.

mark of conformity

Conformity marks are inscribed on appliances and equipment which are generally used by technically inexperienced persons (for example, domestic appliances) and for whom the standards have been established which permit the attribution, by the standardization authority, of a mark of conformity (commonly referred to as a conformity mark).

certification of Quality

Assurance

A laboratory for testing samples cannot certify the conformity of an entire production run: these tests are called type tests. In some tests for conformity to standards, the samples are destroyed (tests on fuses, for example). Only the manufacturer can certify that the fabricated products have, in fact, the characteristics stated.

Quality assurance certification is intended to complete the initial declaration or certification of conformity.

As proof that all the necessary measures have been taken for assuring the quality of production, the manufacturer obtains certification of the quality control system which monitors the fabrication of the product concerned. These certificates are issued by organizations specializing in quality control, and are based on the international standard ISO 9000, the equivalent European standard being EN 29000.

These standards define three model systems of quality assurance control corresponding to different situations rather than to different levels of quality:

c model 3 defines assurance of quality by inspection and checking of final products, c model 2 includes, in addition to checking of the final product, verification of the

manufacturing process. This method applies, for example, to the manufacture of fuses where performance characteristics cannot be checked without destroying the fuse, c model 1 corresponds to model 2, but with the additional requirement that the quality of the design process must be rigorously scrutinized; for example, where it is not intended to fabricate and test a prototype

the standards define several

methods of quality assurance which

correspond to different situations

rather than to different levels of

quality.

B

current demand

The full-load current Ia supplied to the motor is given by the following formulae:

3-phase motor: Ia = Pn x 1,000 ex U x η x cos ϕ 1-phase motor: Ia = Pn x 1,000 U x η x cos ϕ where

Ia: current demand (in amps)

Pn: nominal power (in kW of active power) U: voltage between phases for 3-phase motors and voltage between the terminals for single-phase motors (in volts). A single-phase motor may be connected phase-to-neutral or phase-to-phase.

η: per-unit efficiency, i.e. output kW input kW cos ϕ: power factor, i.e. kW input

kVA input

an examination of the actual

apparent-power demands of different

loads: a necessary preliminary step

in the design of a LV installation.

The examination of actual values of apparent-power required by each load enables the establishment of: c a declared power demand which determines the contract for the supply of energy,

c the rating of the HV/LV transformer, where applicable (allowing for expected increases in load),

c levels of load current at each distribution board.

3.1 induction motors

the nominal power in kW (Pn) of a

motor indicates its rated equivalent

mechanical power output.

The apparent power in kVA (Pa)

supplied to the motor is a function of

the output, the motor efficiency and

the power factor.

Pa = Pn

η

cos

ϕ

motor-starting current

Starting current (Id) for 3-phase induction motors, according to motor type, will be: c for direct-on-line starting of squirrel-cage motors:

v Id = 4.2 to 9 In for 2-pole motors v Id = 4.2 to 7 In for motors with more than 2 poles (mean value = 6 In), where In = nominal full-load current of the motor, c for wound-rotor motors (with slip-rings), and for D.C. motors:

Id depends on the value of starting resistances in the rotor circuits: Id = 1.5 to 3 In (mean value = 2.5 In). c for induction motors controlled by speed-changing variable-frequency devices (for example: Altivar Telemecanique), assume that the control device has the effect of increasing the power (kW) supplied to the circuit motor (i.e. device plus) by 10%.

compensation of reactive-power

(kvar) supplied to induction

motors

The application of this principle to the operation of induction motors is generally referred to as "power-factor improvement" or "power-factor correction".

As discussed in chapter E, the apparent-power (kVA) supplied to an induction motor can be significantly reduced by the use of shunt-connected capacitors.

Reduction of input kVA means a corresponding reduction of input current (since the voltage remains constant). Compensation of reactive-power is particularly advised for motors that operate for long periods at reduced power.

it is generally advantageous for

technical and financial reasons to

reduce the current supplied to

induction motors. This can be

achieved by using capacitors without

affecting the power output of the

motors.

As noted above cos ϕ = kW input so that a kVA input

reduction in kVA input will increase (i.e. improve) the value of cos ϕ.

The current supplied to the motor, after power-factor correction, is given by: Ia x cos ϕ

cos ϕ'

where cos ϕ is the power factor before compensation and cos ϕ' is the power factor after compensation, Ia being the original current.

table of typical values

Table B4 shows, as a function of the rated nominal power of motors, the current supplied to them at different voltage levels

Note: the rated voltages of certain loads

listed in table B4 are still based on 220/380 V. The international standard is now (since

kW HP % 0.37 0.5 64 0.55 0.75 68 0.75 1 72 1.1 1.5 75 1.5 2 78 2.2 3 79 3 4 81 3.7 5 82 4 5.5 82 5.5 7.5 84 7.5 10 85 9 12 86 10 13.5 86 11 15 87 15 20 88 18.5 25 89 22 30 89 25 35 89 30 40 89 33 45 90 37 50 90 40 54 91 45 60 91 51 70 91 55 75 92 59 80 92 63 85 92 75 100 92 80 110 92 90 125 92 100 136 92 110 150 93 129 175 93 132 180 94 140 190 94 147 200 94 150 205 94 160 220 94 180 245 94 185 250 94 200 270 94 220 300 94 250 340 94 257 350 94 280 380 95 295 400 95 300 410 95 315 430 95 335 450 95 355 480 95 375 500 95 400 545 95 425 580 95 445 600 95 450 610 95 475 645 95 500 680 95 530 720 95 560 760 95 600 810 95 630 855 95 670 910 95 710 965 95 750 1020 95 800 1090 95 900 1220 95 1100 1500 95 kVA A A A A A A 0.73 0.79 3.6 1.8 1.03 0.99 0.91 0.6 0.75 1.1 4.7 2.75 1.6 1.36 1.21 0.9 0.75 1.4 6 3.5 2 1.68 1.5 1.1 0.79 1.9 8.5 4.4 2.6 2.37 2 1.5 0.80 2.4 12 6.1 3.5 3.06 2.6 2 0.80 3.5 16 8.7 5 4.42 3.8 2.8 0.80 4.6 21 11.5 6.6 5.77 5 3.8 0.80 5.6 25 13.5 7.7 7.1 5.9 4.4 0.80 6.1 26 14.5 8.5 7.9 6.5 4.9 0.83 7.9 35 20 11.5 10.4 9 6.6 0.83 10.6 47 27 15.5 13.7 12 8.9 0.85 12.3 - 32 18.5 16.9 13.9 10.6 0.85 13.7 - 35 20 17.9 15 11.5 0.86 14.7 - 39 22 20.1 18.4 14 0.86 19.8 - 52 30 26.5 23 17.3 0.86 24.2 - 64 37 32.8 28.5 21.3 0.86 28.7 - 75 44 39 33 25.4 0.86 33 - 85 52 45.3 39.4 30.3 0.86 39 - 103 60 51.5 45 34.6 0.86 43 - 113 68 58 50 39 0.86 48 - 126 72 64 55 42 0.86 51 - 134 79 67 60 44 0.86 57 - 150 85 76 65 49 0.86 65 - 170 98 83 75 57 0.86 70 - 182 105 90 80 61 0.87 74 - 195 112 97 85 66 0.87 79 - 203 117 109 89 69 0.87 94 - 240 138 125 105 82 0.87 100 - 260 147 131 112 86 0.87 112 - 295 170 146 129 98 0.87 125 - 325 188 162 143 107 0.87 136 - 356 205 178 156 118 0.87 159 - 420 242 209 184 135 0.87 161 - 425 245 215 187 140 0.87 171 - 450 260 227 200 145 0.87 180 - 472 273 236 207 152 0.87 183 - 483 280 246 210 159 0.87 196 - 520 300 256 220 170 0.87 220 - 578 333 289 254 190 0.87 226 - 595 342 295 263 200 0.88 242 - 626 370 321 281 215 0.88 266 - 700 408 353 310 235 0.88 302 - 800 460 401 360 274 0.88 311 - 826 475 412 365 280 0.88 335 - 900 510 450 400 305 0.88 353 - 948 546 473 416 320 0.88 359 - 980 565 481 420 325 0.88 377 - 990 584 505 445 337 0.88 401 - 1100 620 518 472 365 0.88 425 - 1150 636 549 500 370 0.88 449 - 1180 670 575 527 395 0.88 478 - 1250 710 611 540 410 0.88 508 - 1330 760 650 574 445 0.88 532 - 1400 790 680 595 455 0.88 538 - 1410 800 690 608 460 0.88 568 - 1490 850 730 645 485 0.88 598 - 1570 900 780 680 515 0.88 634 - 1660 950 825 720 545 0.88 670 - 1760 1000 870 760 575 0.88 718 - 1880 1090 920 830 630 0.88 754 - 1980 1100 965 850 645 0.88 801 - 2100 1200 1020 910 690 0.88 849 - - 1260 1075 960 725 0.88 897 - - 1350 1160 1020 770 0.88 957 - - 1450 1250 1100 830 0.88 1076 - - 1610 1390 1220 925 0.88 1316 - - 1980 1700 1500 1140 kvar kVA A A A A A A 0.93 0.31 0.62 2.8 1.4 0.8 0.77 0.71 0.47 0.93 0.39 0.87 3.8 2.2 1.3 1.1 1 0.72 0.93 0.48 1.1 4.8 2.8 1.6 1.3 1.2 0.88 0.93 0.53 1.6 7.2 3.7 2.2 2 1.7 1.3 0.93 0.67 2.1 10.3 5.2 3 2.6 2.2 1.7 0.93 0.99 3 13.7 7.5 4.3 3.8 3.3 2.4 0.93 1.31 4 18 9.9 5.7 5 4.3 3.3 0.93 1.59 4.8 22 11.6 6.6 6.1 5.1 3.8 0.93 1.74 5.2 22 12.5 7.3 6.8 5.6 4.2 0.93 1.80 7 31 17.8 10.3 9.3 8 5.9 0.93 2.44 9.5 42 24 13.8 12.2 10.7 7.9 0.93 2.4 11.3 - 29 16.9 15.4 12.7 9.7 0.93 2.6 12.5 - 32 18 16.4 13.7 10.5 0.93 2.50 13.6 - 36 20 19 17 13 0.93 3.37 18.3 - 48 28 25 21 16 0.93 4.12 22.4 - 59 34 30 26 20 0.93 4.89 26.6 - 69 41 36 31 23 0.93 5.57 30 - 79 48 42 36 28 0.93 6.68 36 - 95 55 48 42 32 0.93 7.25 39 - 104 63 54 46 36 0.93 8.12 44 - 117 67 59 51 39 0.93 8.72 47 - 124 73 62 55 41 0.93 9.71 53 - 139 79 70 60 45 0.93 11.10 60 - 157 91 77 69 53 0.93 11.89 64 - 168 97 83 74 56 0.93 10.98 69 - 182 105 91 80 62 0.93 11.66 74 - 190 109 102 83 65 0.93 13.89 88 - 225 129 117 98 77 0.93 14.92 93 - 243 138 123 105 80 0.93 16.80 105 - 276 159 137 121 92 0.93 18.69 117 - 304 176 152 134 100 0.93 20.24 127 - 333 192 167 146 110 0.93 23.84 149 - 393 226 196 172 126 0.93 24 151 - 398 229 201 175 131 0.93 25.55 160 - 421 243 212 187 136 0.93 26.75 168 - 442 255 221 194 142 0.93 27.26 172 - 452 262 230 196 149 0.93 29.15 183 - 486 281 239 206 159 0.93 32.76 206 - 541 312 270 238 178 0.93 33.79 212 - 557 320 276 246 187 0.93 30.78 229 - 592 350 304 266 203 0.93 33.81 252 - 662 386 334 293 222 0.93 38.44 286 - 757 435 379 341 259 0.93 39.45 294 - 782 449 390 345 265 0.93 42.63 317 - 852 483 426 378 289 0.93 44.80 334 - 897 517 448 394 303 0.93 45.66 339 - 927 535 455 397 306 0.93 47.98 356 - 937 553 478 421 319 0.93 51 379 - 1041 587 490 447 336 0.93 54 402 - 1088 602 519 473 350 0.93 57.1 424 - 1117 634 544 499 374 0.93 60.84 453 - 1183 672 578 511 388 0.93 64.60 481 - 1258 719 615 543 420 0.93 67.63 504 - 1325 748 643 563 431 0.93 68.50 509 - 1334 757 653 575 435 0.93 70.40 538 - 1410 804 691 610 459 0.93 72.26 566 - 1486 852 738 643 487 0.93 80.64 600 - 1571 899 781 681 516 0.93 85.12 634 - 1665 946 823 719 544 0.93 91.33 679 - 1779 1031 871 785 596 0.93 95.81 713 - 1874 1041 913 804 610 0.93 101.88 758 - 1987 1135 965 861 653 0.93 107.95 804 - - 1192 1017 908 686 0.93 114 849 - - 1277 1098 965 729 0.93 121.68 905 - - 1372 1183 1041 785 0.93 136.86 1019 - - 1523 1315 1154 875 0.93 167.35 1245 - - 1874 1609 1419 1079

B

3.2. direct-current motors

D.C. motors are mainly used for specific applications which require very high torques and/or variable speed control (for example machine tools and crushers, etc.).

Power to these motors is provided via speed-control converters, fed from 230/400 V 3-phase a.c. sources; for example, Rectivar 4 (Telemecanique).

The operating principle of the converter does not allow heavy overloading. The speed controller, the supply line and the protection are therefore based on the duty cycle of the motor (e.g. frequent starting-current peaks) rather than on the steady-state full-load current.

For powers i 40 kW, this solution is progressively replaced with a speed-changing variable-frequency device and an asynchronous motor. It is still used for gradual starters and/or retarders.

M

V power-supply network

In

Im

fig. B5: diagram of a low-power speed controller.

table B6: progressive starters with voltage ramp.

motor maximum power motor GRADIVAR catalogue number weight 220 V 380 V 415 V 440 V (60 Hz) In Ith kg kW kW kW kW A A 4 5.5 6 - 12 20 VR2-SA3171 3.30 - - - 6.5 12 20 VR2-SA3173 3.30 5.5 7.5 8 - 16 30 VR2-SA3211 5.10 - - - 8.5 16 30 VR2-SA3213 5.10 11 18.5 20 - 37 60 VR2-SA3281 5.50 - - - 21.5 37 60 VR2-SA3283 5.50 18.5 30 33 - 60 100 VR2-SA3361 5.50 - - - 35 60 100 VR2-SA3363 5.50 22 37 40 - 72 130 VR2-SA3401 5.60 - - - 42 72 130 VR2-SA3403 5.60 - 55 60 - 105 200 VR2-SA3441 11.00 - - - 63 105 200 VR2-SA3443 11.00

motor maximum power motor GRADIVAR catalogue number weight 220 V 380 V 415 V 440 V (60 Hz) In Ith kg kW kW kW kW A A 1.5 3 3.3 - 7 10 VR2-SA2121 1.95 - - - 3.5 7 10 VR2-SA2123 1.95 4 5.5 6 - 12 20 VR2-SA2171 3.10 - - - 6.5 12 20 VR2-SA2173 3.10 5.5 7.5 8 - 16 30 VR2-SA2211 4.90 - - - 8.5 16 30 VR2-SA2213 4.90 11 18.5 20 - 37 60 VR2-SA2281 5.30 - - - 21.5 37 60 VR2-SA2283 5.30 18.5 30 33 - 60 100 VR2-SA2361 5.30 - - - 35 60 100 VR2-SA2363 5.30 22 37 40 - 72 130 VR2-SA2401 5.40 - - - 42 72 130 VR2-SA2403 5.40 - 55 60 - 105 200 VR2-SA2441 10.00 - - - 63 105 200 VR2-SA2443 10.00

quoted by the manufacturer

(i.e. cos ø = 1).

the currents are given by:

c

3-phase case:

Ia = Pn*

e

x U

c

1-phase case:

Ia = Pn*

U

where U is the voltage between the

terminals of the equipment.

The currents are given by: c 3-phase case: Ia = Pn* ex U c 1-phase case: Ia = Pn* U

where U is the voltage between the terminals of the equipment.

Note: at the instant of switching on, the cold filament gives rise to a very brief but intense peak of current.

* Ia in amps; U in volts. Pn is in watts. If Pn is in kW, then multiply the equation by 1,000.

nominal current demand

power 1-phase 1-phase 3-phase 3-phase kW 127 V 230 V 230 V 400 V 0.1 0.79 0.43 0.25 0.14 0.2 1.58 0.87 0.50 0.29 0.5 3.94 2.17 1.26 0.72 1 7.9 4.35 2.51 1.44 1.5 11.8 6.52 3.77 2.17 2 15.8 8.70 5.02 2.89 2.5 19.7 10.9 6.28 3.61 3 23.6 13 7.53 4.33 3.5 27.6 15.2 8.72 5.05 4 31.5 17.4 10 5.77 4.5 35.4 19.6 11.3 6.5 5 39.4 21.7 12.6 7.22 6 47.2 26.1 15.1 8.66 7 55.1 30.4 17.6 10.1 8 63 34.8 20.1 11.5 9 71 39.1 22.6 13 10 79 43.5 25.1 14.4

table B8: current demands of resistive heating and incandescent lighting (conventional or halogen) appliances.

3.4. fluorescent lamps and related equipment

the power in watts indicated on the

tube of a fluorescent lamp does not

include the power dissipated in the

ballast.

the current is given by:

Ia =

Pballast + Pn

U x cos ø

If no power-loss value is indicated for

the ballast, a figure of 25% of Pn may

be used.

standard tubular fluorescent

lamps

The power Pn (watts) indicated on the tube of a fluorescent lamp does not include the power dissipated in the ballast.

The current taken by the complete circuit is given by:

Ia = Pballast + Pn U x cos ø

where U = the voltage applied to the lamp, complete with its related equipment. with (unless otherwise indicated): c cos ø = 0.6 with no power factor (PF) correction* capacitor,

c cos ø = 0.86 with PF correction* (single or twin tubes),

c cos ø = 0.96 for electronic ballast. If no power-loss value is indicated for the ballast, a figure of 25% of Pn may be used. Table B8 gives these values for different arrangements of ballast.

* "Power-factor correction" is often referred to as "compensation" in discharge-lighting-tube terminology.

B

arrangement of tube power current (A) at 220V/240 V tube lamps, starters power consumed PF not PF electronic length and ballasts _{(W) (1) (W) corrected corrected ballast (cm)}

single tube with starter 18 27 0.37 0.19 60

36 45 0.43 0.24 120

58 69 0.67 0.37 150

single tube without 20 33 0.41 0.21 60

starter (2) with 40 54 0.45 0.26 120

external starting strip _{65 81 0.80 0.41 150}

twin tubes with starter 2 x 18 55 0.27 60

2 x 36 90 0.46 120

2 x 58 138 0.72 150

twin tubes without starter 2 x 40 108 0.49 120

single tube with 32 36 0.16 120

high frequency ballast 50 56 0.25 150

cos ø = 0.96

twin tubes with high- 2 x 32 72 0.33 120

frequency ballast 2 x 50 112 0.50 150

cos ø = 0.96

(1) Power in watts marked on tube.

(2) Used exclusively during maintenance operations.

table B10: current demands and power consumption of commonly-dimensioned fluorescent lighting tubes (at 220 V/240 V - 50 Hz).

compact fluorescent tubes

Compact fluorescent tubes have the same characteristics of economy and long life as classical tubes.

They are commonly used in public places which are permanently illuminated (for example: corridors, hallways, bars, etc.) and can be mounted in situations otherwise illuminated by incandescent lamps.

type of lamp lamp power current at power consumed 220/240 V

(W) (A)

globe lamps with 9 9 0.090

integral ballast 13 13 0.115 cos ø = 0.5 (1) _{18 18 0.160} 25 25 0.205 electronic lamps 9 9 0.070 cos ø = 0.95 (1) 11 11 0.090 15 15 0.135 20 20 0.155

lamps with type 5 10 0.185

starter single 7 11 0.175

only "U" form _{9 13 0.170}

incorporated cos ø ≈ 0.35 _{11 15 0.155}

(no ballast) _{type 10 15 0.190}

double 13 18 0.165

"U" form _{18 23 0.220}

cos ø ≈ 0.45 _{26 31 0.315}

(1) Cos ø is approximately 0.95 (the zero values of V and I are almost in phase) but the power factor is 0.5 due to the impulsive form of the current, the peak of which occurs "late" in each half cycle.

table B11: current demands and power consumption of compact fluorescent lamps (at 220 V/240 V - 50 Hz).