LOW VOLTAGE XLPE INSULATED POWER CABLES ...tkne.net/downloads/power/maintainaneoflines/powercabels.pdfLOW VOLTAGE XLPE INSULATED POWER CABLES Advanced Cable Solutions Through Technology

LOW VOLTAGE XLPE INSULATEDPOWER CABLES

Advanced Cable Solutions Through Technology and Innovation

B I C C

Introduction .................................................................................................................................... 1

Customer Service............................................................................................................................ 2-3

Product Range ................................................................................................................................ 4

Specification and Construction ...................................................................................................... 4 – 5

Salient Features of Ducab Cables Design .................................................................................... 6

Installation and Electrical Data ...................................................................................................... 6 – 19

XLPE Insulated Cables to BS 5467: Technical Data Tables ........................................................ 20-33

● 600/1000V rated, Copper and Aluminium Conductors........................................................... 20-31

● Single Core Cables................................................................................................................ 20-21

● Two Core Cables................................................................................................................... 22-23

● Three Core Cables................................................................................................................. 24-25

● Four Core Cables .................................................................................................................. 26-27

● Four Core Cables with Reduced Neutral Conductors........................................................... 28-29

● Three and Four Core Armoured Cables................................................................................. 30

● 1900/3300V rated, Armoured Copper Conductors.................................................................. 31

● XLPE insulated Lead Sheathed Armoured Cables to BS 5467............................................... 32-33

Advantages of XLPE Insulated Cables........................................................................................... 34

LSF Cables...................................................................................................................................... 34

XLPE Cable Voltage Drop Data for partial loads........................................................................... 35

Components Reference Chart......................................................................................................... 36-37

Ducab is listed in the following publication issued by the Department of Trade and Industry ofthe United Kingdom.

“THE DTI QA REGISTER - PRODUCTS AND SERVICES LIST”

Only those companies whose quality system is assessed and certified by U.K. accredited certificationbodies appear in the above publication.

CONTENTS

Page

B I C C

INTRODUCTION

Dubai Cable Company (Private) Limited – Ducab – is a joint venture between the Government of Dubai, the Governmentof Abu Dhabi. Ducab is located on a site of 54 hectares in Jebel Ali, Dubai, in the United Arab Emirates. A major factoryexpansion took place in 1991 with production capacity being more than doubled. In 1999, Ducab again increasedproduction capacity for low voltage cables and commissioned a world class production and testing facilities for DucabPowerplus Medium Voltage cables. In 2001, Ducab installed the second Medium Voltage CCV line. The currentfactory floor area is 16,000 m2. Ducab manufactures electric cables to the highest quality standards.

This catalogue provides working information on Ducab’s complete range of XLPE Power Cables rated up to 3.3 kV andalso includes data on components. Separate catalogues are available for Ducab’s range of Control and Auxiliary Cables,Wiring Cables, Ducab Smokemaster LSF Cables and Ducab Powerplus Medium Voltage Cables. Details ofPVC Power Cables are available on request.

Due to the wide range of cables in the catalogue, it is advisable, when ordering, to provide as much information aspossible. Please use the following table as a guide:

Specialist advice and assistance on all matters concerning PVC or XLPE insulated Power cables isavailable from Ducab Sales Offices or direct from Dubai Cable Company (Private) Limited,P. O. Box 11529, Dubai, U. A. E., Tel: 971-4-8082500, Fax: 971-4-8082511. E-mail: [email protected] Website: www.ducab.ae

TECHNICAL ADVISORY SERVICE

The following details will ensure that your enquiries and orders are dealt with quickly and efficiently:

1. Length of cables required and individual drum lengths.*

2. Voltage designation.

3. Relevant British or International Standard.

4. Number of cores.

5. Conductor size and, where applicable, size of reduced neutral conductor.

6. Conductor material i.e. copper, aluminium.

7. Type of insulation.

8. Type of bedding.

9. Type of armour.

10. Type of outer sheath.

11. Any other special requirement, e.g. circular conductors, special PVC sheath material, drum

weight limitation, etc.

* Cables are normally supplied in lengths of 300 metres, 500 metres and 1000 metres depending on conductor size. Other lengths can be supplied if required.

ORDERING ADVICE

1

B I C C2

Dubai Cable Company - Ducab - is the leading cable manufacturer in the United Arab Emirates and, since 1979, hasbeen meeting the requirements of customers throughout the Middle and Far East. Ducab’s cables are used by some ofthe most demanding utilities in the world, for the following reasons:

Product QualityDucab is committed to supplying its customers with the highest quality of product and of service. Ducab’s Powercables have been type approved by Lloyd’s Register of the UK and have undergone rigoroustype testing by the British Standards Institution (via BASEC) of the UK. They fully conformto BS 6346 and BS 5467 specifications for PVC and XLPE insulated cables respectively, forelectricity supply, up to and including 600/1000 V ratings.

In addition, Ducab was presented with the Dubai Quality Award 1994, for the best localindustrial company of the year. Four years later, Ducab was presented with the Dubai QualityAward ’98 Gold Category. The Gold Award rewards the most distinguished companies whichare judged to be world class.

ReliabilitySpecifying the right cable for a particular application is the first step. The key to reliability however, is in themanufacturing process. The cable must be free from material and manufacturing defects, and weaknesses that will berevealed in service.

Ducab constantly monitors its manufacturing processes and operates stringent quality assurance procedures to givelong term reliability. This is of vital significance where cables are to be installed in locations where future accesswould be difficult and this is where Ducab’s reputation and the resources give peace of mind.

PerformanceOptimum cable performance can be provided only by a company such as Ducab, with access to the latestdevelopments in conductor, insulation and protective materials technology. In addition, Ducab’s knowledge ofapplication requirements throughout the Middle and Far East is an assurance of high performance.

Where required, Ducab can incorporate special features, for example to give the cable low smoke and fume (LSF) orreduced flame propagation characteristics, or to resist damage from chafing or impacts.

Our experienced Technical staff can provide guidance on cable selection and installation and can ensure that you getthe right cable for the job.

SafetyDucab is able to maintain a close watch on world developments in cable technology and regulations and therefore ensurethat its products are designed and constructed to be hazard-free under the prescribed conditions of use.

Ducab uses only tried and tested materials and processes in full compliance with all relevantBritish and International Standards. Our cables are therefore manufactured for safe use withoutrisk to health on the understanding that users will exercise the same degree of care in theirselection and application.

Safety is an important issue for Ducab, and the strictest standards are adhered to throughoutthe company. Ducab is proud of its safety record and has been awarded RoSPA (Royal Societyfor the Prevention of Accidents) Gold Awards for safety from 1991 to 1999. In 2000, Ducabwas awarded the prestigious President’s Award for Health and Safety which is a recognitionof Ducab winning 10 consecutive annual Gold awards and acknowledges Ducab’s totalcommitment to health and safety. In 2002, Ducab was declared the joint winner of theManufacturing Industry Sector Award from RoSPA.

Ducab is the first organisation in the Middle East to receive accreditation to BS 8800 by the BASEC (BritishApprovals Service for Cables). Certification to BS 8800 provides a recognisable Occupational Health and SafetyManagement standard against which an organisation’s management systems can be assessed and certified. Based onthe structure of ISO 14001, the standard requires continual improvement in health and safety related activities.

CUSTOMER SERVICE

B I C C 3

Quality Management System Certified to ISO 9001Ducab’s Quality Management System conforms to the ISO 9001:1994 International Quality SystemStandard and is certified by the British Standards Institution who are an internationally recognised qualityauthority accredited in the UK and throughout the world. Ducab also holds ISO 9001:1994 certificateissued independently by BASEC.

Certification to the ISO 9001 International standard demonstrates that Ducabhas drawn up written procedures to ensure full compliance with allrequirements of the standard and that these procedures are followed by everydepartment in the company, thus ensuring that the goods leaving Ducab’sfactory are of the highest quality and meet each customer’s requirements inevery respect.

Ducab is particularly proud to have achieved certification to the stringent ISO9001:1994 standard as it is an independent conformation that it designs, manufactures and tests cablesconsistently to accepted standards. ISO 9001 is widely used throughout Europe, and is therefore areassurance to Ducab’s customers that the products and service supplied by the company are equal to thebest in the world.

Environmental Management System Certified to ISO 14001Ducab’s Environmental Management System conforms to the ISO 14001:1996 InternationalEnvironmental Management Standard and is certified by the British Standards Institution who are aninternationally recognised certifying authority accredited in the UK and throughout Europe.

Certification to the ISO 14001:1996 International standard shows that Ducabhas a well defined structure and established working practices aimed at limitingits impact on the environment. Measurement and monitoring of effects, issuingwork instructions, training of personnel and taking corrective actions are allessential elements to limiting the impact on the environment. Ducab has setimprovement targets to reduce the significant environmental impacts associatedwith its activities.

Ducab is proud to be the first cable manufacturer in the region to achieve certification to ISO 14001 andthis certification along with its quality, business success and safety record demonstrates that Ducab is aworld class organisation and can hold its head up to any business community throughout the world.

BASEC CertificationDucab is also proud to hold a Product Marketing Licence issued by BASEC(British Approvals Service for Cables) for several cables in its product range.

Customer SatisfactionDucab’s customer satisfaction programme, ‘The Value Edge’ is designed to ensure that customers receivea consistently high level of service from Ducab’s dedicated staff.

B I C C4

INSULATIONThe rated voltage level of the cable depends on the dielectric strength and thickness of the insulation.

Material: Cross-linked polyethylene (XLPE) Type GP8 as per BS 7655:Section 1.3.

Colour Masterbatch:Ultra-violet (UV) resistant polyethylene masterbatch is used for colouring of insulation. This protects the insulationfrom deterioration when exposed to continuous sunlight.

Core identification is by colour as follows (unless otherwise agreed):No. of cores Core Colours

1 Red or Black2 Red and Black3 Red, Yellow and Blue4 Red, Yellow, Blue and Black5 Red, Yellow, Blue, Black and Green/Yellow

For providing circular shape to the cable non-hygroscopic compatible fillers (wherever necessary) are included betweenlaid up cores.

METALLIC SCREEN: If required by the customer screening may be provided for electrical shielding.

Material:Copper tapeAluminium PE tape along with tinned copper drain wire (for providing screen continuity).

SPECIFICATION AND CONSTRUCTION

CONDUCTORSIt is the current carrying component of the cable.

Material:Plain, stranded, compacted copper as per BS 6360/IEC:228 Aluminium, stranded, compacted conductors

CORE IDENTIFICATION

FILLERS

PRODUCT RANGEVoltage range: 0.6/1kV and 1.9/3.3 kV

Cable Types:1) Armoured/unarmoured XLPE insulated cables 2) Lead sheathed cables 3) Copper or Aluminium PE tape (with drain wire) shielded

Cable sizes: Single core up to and including 1000 mm2

2 core up to and including 300 mm2



Specification:BS 5467..........................for XLPE insulated armoured cablesBS 7889..........................for XLPE insulated single core unarmoured cables IEC 60502 (Part 1) ........for XLPE insulated single/multicore armoured/unarmoured cablesAny other International Specification as per VDE/DIN,GOST and as per customer’s specifications.

B I C C 5

BARRIER TAPE:

Material:

Polypropylene/PETP tape is used as a barrier tape over the laid up cores.

Functions:

Holds the cores together and prevents them from opening out.

Works as a separator between different polymers used in a cable.

LEAD SHEATH

Material:

Extruded Lead Alloy “E” Sheath.

Thickness of applied lead sheath is as per EEMUA - 133 (Engineering Equipment and Material Users Association).

Function:

Protects insulation from corrosion by petroleum products in oil and gas industries.

Extruded bedding serves as a bedding for the armour and as a protection for the laid-up cores.

Material:

Extruded PVC Type 9 Compound as per BS 7655.

Reduced propagation flame retardant (RPLHCL)/RP PVC Compound for reduced flame propagation characteristics.

Smokemaster Low smoke and fume for installations where fire hazards exist.

Armour provides mechanical protection to the cable. It also serves as an Earth Continuity Conductor (ECC).

One layer of round wire is applied helically over the bedding.

Material:

Galvanised round steel wire (GSW).

Galvanised round steel wire (GSW) along with tinned copper wires (TCW) for maintaining specified conductivityof armour (if required by the customer).Aluminium round wire armour (AWA) is generally used for single core ac circuits as aluminium is a non-magnetic

material and this will reduce losses due to armour.

Note: Aluminium glands should be used in conjunction with cables having aluminium wire armour.

Following types of materials may be specified for oversheathing.

● General Purpose: Extruded PVC Type 9 Compound as per BS 7655.

● Medium Density Polythylene (MDPE): Offers higher protection from water ingress and mechanical abrasion.

● Anti Termite: Termite resistance can be built in both types described above by compounding with proper additives.

● Reduced Propagation (RP): Retards propagation of flame in fire situation. (Oxygen Index ≈30)

● Reduced Propagation and Low Acid Fumes (RPLHCL): Retards propagation of flames and gives low emission of

hydrochloric acid fumes. (OI ≈ 30 & acid gas emission is less than 18 %)

● Smokemaster Low Smoke & Fume (LSF): Smokemaster cables are ideal for installations where the dense

black smoke generated by PVC cables in a fire are a danger to people. Smokemaster is characterised by the

features as Oxygen Index greater than 35, acid-gas liberation almost nil (<0.5%) and smoke density within controllable

limit of 40% smoke density. Smokemaster cables are offered to BS 6724.

OVERSHEATH - FINISH

BEDDING

ARMOUR

B I C C6

INSTALLATION

Whichever form of conductor is used, XLPE insulated cables are simple to handle, install and joint. All the cablesdescribed in this publication can be used indoors or outdoors, but some reservations are necessary concerning cables fordirect burial in the ground or for use in sustained wet conditions as follows:

(i) Unarmoured cables are not generally recommended for laying directly in the ground.

(ii) Cables laid directly in the ground, particularly in sustained wet conditions, should have extruded bedding andpreferably MDPE - Medium Density Polyethylene - as the outersheath material.

Other important factors to be taken into account are:

Sheath DamageCare should be taken to ensure that the oversheath is not damaged during installation. This is especially important wherealuminium wire armour is used, as ingress of moisture could lead to corrosion or ultimate loss of earth continuity.

SALIENT FEATURES OF DUCAB CABLE DESIGN(1) XLPE insulation Ultra-violet (UV) colour masterbatch:

Ultra-violet (UV) resistant polyethylene masterbatch is used for colouring of insulation. This protects the insulationfrom deterioration when exposed to continuous sunlight.

(2) Polypropylene/PETP tape over the laid up cores:

Acts as a separator between different polymers used in a cable.

(3) Fillers:

For ensuring proper circular shape to the cable, non-hygroscopic compatible fillers (wherever necessary) are includedbetween laid up cores.

(4) Special requirements:

Ducab cables can be custom designed to incorporate special requirements of the client as follows:

(a) Screening: Copper tape or Aluminium PE tape (along with tinned copper drain wire) can be used for shieldingpurposes.

(b) Tinned copper wire can be used along with galvanised round steel wires to maintain specified armour conductivityrequirements.

(c) Reduced propagating flame retardant bedding (RPLHCL/RP) and outersheath material can be offered to meetreduced flame propagation characteristics and low hydrogen acid gas emission.

(d) Cable with bedding and outersheath material of special LSF (low smoke and fume) compound can be offered forinstallations where fire and its associated problems - the emission of smoke and toxic fumes - offer a seriouspotential threat. (For details on LSF cables refer page 34)

(e) In water logged areas or where the cables are required to be abrasion resistant, cable with medium densitypolyethylene (MDPE) can be offered.

(f) For protection from insects, anti-termite protection can be added to the outersheath.

B I C C 7

Minimum installation radiusCable should not be bent during installation to a radius smaller than that recommended below. Wherever possible largerinstallation radii should be used.

Table 1

Type of Cable Overall Diameter (D)Minimum internal

radius of bend

Circular copper conductors armoured or unarmoured Any 6D

Shaped copper or aluminium conductors, armouredor unarmoured

For lead sheathed cables

Any

Any

8D

12D

CABLE SUPPORT SPACING

As per Clause 522-08-04 of 16 th Edition of IEE Wiring Regulations where the cable is not continuously supported itshall be supported by suitable means at appropriate intervals in such a manner that the cable does not suffer damage byits own weight.

ConnectorsThe use of compression type connectors is recommended for XLPEinsulated cables since the use of solderedconnectors would limit the maximum short circuit temperature of the cable to 160˚C (and consequently reduce the finalshort circuit current by approximately 30 per cent).

Overhead terminationsUltra violet resistant sleeving or taping should be provided on XLPE insulated cores to avoid degradation due toexposure to solar rays.

Armoured Single Core Cables for AC OperationSingle core cable armour should not be bonded/earthed at both ends, otherwise it carries a circulating current, whichmay cause overheating in the cables, sometimes resulting in early failure. However single end bonding results in aninduced voltage (of low magnitude) at the unearthed end of the armour. Ducab strongly recommend use of an InsulatedAdaptor in the cable gland, while terminating single core cables for AC operation. The insulated adaptor could beprovided as per part design No. 481 AA - Series.

Single core cables for AC operation should not pass through steel conduit or steel gland plate, as it produces a heatingeffect.

B I C C8

CURRENT RATINGS

Current ratings for XLPE insulated cables for ‘ground’and ‘duct’installation are derived from the latest issue of ERAReport 69-30 Part 5 which is based upon IEC Publication 287. The ratings for ‘In Air’installation are taken from IEEWiring Regulations, 16th Edition.

All the ratings given are for single circuits installed thermally independent of other circuits or any other heat source andon the basis of the standard conditions of installation given in relevant Tables between 18 to 34. For other ambient orground temperatures, depth of laying, soil thermal resistivity, the rating must be multiplied by relevant rating factors inTables 2 to 6 and 8 to 12.

It should be noted that if XLPE insulated cables, are subjected to operating temperatures appreciably higher than the90˚C permissible for continuous operation, the insulation will undergo premature ageing thus affecting the normal lifeof the cable. However, limiting maximum conductor temperature to 105˚C during overloads with duration not exceeding4 hours on any one occasion, or a maximum of 100 hours in any 12 consecutive months, or a total of 500 hours in thecable’s lifetime, would be tenable.

IEE Wiring Regulations 16th edition - requirement for cables

The IEE Wiring Regulations for installation and selection of cables cannot be approached in isolation from the otherequipment in the installation. In particular the devices providing protection against overload, short circuit, shock byindirect contact and over-heating of protective conductors during an earth fault, affect the selection of cables.

For guidance and assistance, given below are some of the IEE Wiring Regulation’s requirements for cables:

Protection against overload current: (Clause 433-01-01 of the 16th Edition of theIEE Wiring Regulations)

This states the requirements which effectively determine the sustained current ratios of the cable viz:

(i) The current rating of the cable should not be less than the nominal current or current setting of the device providingprotection against overload, which in turn should be not less than the circuit current.

(ii) The overload protection should operate at not more than 1.45 times the current rating of the cable.

The second requirement (ii) is met if the first (i) is met when the protective device is any of the standard fuses or MCB’smentioned in the regulations,except rewirable types of fuse to BS 3036.

With fuses to BS 3036 the current ratings of the cable should not be less than 1.38 times the fuse rating to satisfy (ii).

Protection against short circuit: (Clause 434 of the 16th Edition of the IEEWiring Regulations)

The cable has to have adequate short-circuit capacity for the current let through by the device providing short circuitprotection for the time it will flow.

The formula in Section 434-03-03 is effectively that used by cable makers to give the short-circuit ratings in theirpublications.

If the device providing protection against short circuit is the same as that providing protection against overload and,therefore, has a rating not higher than the rating of the cables, the short circuit capacity of the cable will automaticallybe adequate, there is no need to check.

B I C C 9

Protection against indirect contact by interruption of supply: (Clause 412 ofthe 16th Edition of IEE Wiring Regulations)

Protection against shock due to contact with exposed conductive parts of equipment during a fault to earth is deemed tobe provided if disconnection due to flow of the fault current through the protective device will occur, either

within 0.4 seconds for final circuits supplying socket outlets. (Table 41A of the 16th Edition of the IEE WiringRegulations)

or

within 5 seconds for final circuits supplying fixed equipment. (Clause 413-02-12 of the 16th Edition of the IEE WiringRegulations)

Regulation 413 gives values of earth fault loop impedances which satisfy these conditions when the standard types ofprotective devices are used.

Cables make the major contribution to earth fault loop impedance, but the impedance of the supply external to theinstallation has to be taken into account.

It is not possible to say what maximum length of standard cables may be used in the installation without exceeding therequirements for earth fault loop impedance in the absence of information on the external impedance for the particularinstallation.

Table 16 gives estimated values of the contribution to earth loop impedance by XLPE insulated copper conductor, steelwire armoured cables to BS 5467.

Cross sectional areas of protective conductors: (Clause 543 of the 16th Edition ofIEE Wiring Regulations)Regulation 543 explains how the cross sectional area of the circuit protective conductor should be calculated to avoid itover-heating during a fault to earth. Again the area required depends on the characteristics of the device providingprotection against short circuit.

The steel wire armour of standard cables to BS 5467 (XLPE) and BS 6346 (PVC) provides the required area, or more,when the protective device is one of the standard fuses or MCB’s with a rating not higher than the current rating of thecable (assuming disconnection within 5 seconds).

For the most of the cables the armour is still adequate when the fuse rating is one or two steps, or even more, above thecurrent rating of the cable, the margins being greater for the small sizes and 4 core cables than for the larger sizes andtwo core cables.

B I C C10

Voltage drop is normally only of importance for cables of voltage rating 600/1000V or below. If the installation is to beincompliance with Regulation 525 of the 16th Edition of the IEE Wiring Regulations, it is stipulated that “the voltagedrop within the installation does not exceed a value appropriate to the safe functioning of the associated equipment innormal service. The requirement is deemed to be satisfied if the drop in voltage from the origin of the installation(usually supply terminals) and the fixed current using equipment does not exceed 4 per cent of the nominal voltage ofthe supply, disregarding starting conditions.”

(Note: Diversity can be taken into account when calculating voltage drop).

Since the actual power factor of the load is often not known, the most practical approach to the question of voltage dropis to assume the worst conditions i.e. where the phase angle of the load is equal to that of the cable. The voltage dropvalues in the tables have been based on this assumption. For conductor sizes up to and including 120 mm2 the figuresprovided apply with sufficient accuracy where the power factor lies between 0.6 lagging and 1.0, and for large cableswhere the power factor of the load does not exceed 0.8 lagging. Where the phase angles of the loads fall outside thisrange, the voltage drop deduced from the tables may be unduly conservative and more exact methods of calculationshould be employed.

The values of voltage drop for 600/1000 V rated cables are given in the current rating tables.

In those cases where the actual current differs greatly from the tabulated current rating, the results obtained from thetables are only approximate; for a more accurate assessment, allowance should be made for the change in conductorresistance with operating temperature. Refer to page 35 and Table 32 for details. It should also be ensured that the cablesize ultimately selected is capable of carrying the required current under the site conditions of installation.

Values of voltage drop are tabulated for a current of one ampere for a 1 metre run, i.e. for a distance of 1 metre alongthe route taken by the cables, and represent the effect of the voltage drop in all the circuit conductors. For balanced threephase ac circuits, the values relate to the line voltage. For any given run the values need to be multiplied by the lengthof the run (in metres) and by the current (in amperes) that the cables are to carry.

Examples: Consider a route of 200 metres of 4 Core armoured cable to be installed in air and to carry 100 amperes loadper phase, with the supply voltage being 415 volts, three phase 50 Hz and the cable to be Copper XLPE/SWA/PVC.

Using the tables:

Let Vd be the voltage drop in volts.

Vd = mV x I x L or mV = Vd x 10001000 I x L

where I = Current in amperes L = Route length in metres mV = Approximate volt drop/ampere/metre

Assume maximum permissible volt drop = 4 per cent of 415 volts = 16.6 volts

Substitute for current, route length and maximum permissible volt drop

then mV = 16.6 x 1000 = 0.83200 x 100

Select a cable from the relevant Current Rating Table 27 such that the “mV value” from the voltage drop column is equalto or less than the 0.83 mV calculated, ensuring that it will carry the current. It will be seen that this value is 0.6 givinga cable size of 70mm2. However, 100 Amp load could be less than 80% current carrying capacity of 50mm2 cable, inwhich case of 50 mm 2 cable will suffice.

Note: Please refer to pages 30 and 35 for additional information on voltage drop.

VOLTAGE DROP

B I C C 11

RATING FACTORS

Rating factors for ground temperature

Rating factors for variation in thermal resistivity of soil(average values)

CABLES LAID DIRECTLY IN GROUND

Where the conditions of installation differ from those defined in the current rating tables, the following rating factors may be usedfor cables size selection.

Ratings for cables installed directly in the ground are based on values of soil temperature and soil thermal resistivity which aregenerally representative of conditions in the United Kingdom. Rating factors to take account of variation in ground temperatures aregiven in Table 2. Where conditions of operation can be fairly accurately estimated and knowledge of the soil along the route isavailable, it is possible to determine the ratings more precisely by the use of the soil thermal resistivity factors, grouping factors, andfactors for the depths of laying given in Tables 3 to 6. These factors are more fully tabulated in ERA Report 69 - 30 Part II Tables61 - 71.

In ERA Report 69-30 Part III, the types of load are classified under three headings, viz:

Type A Cables carrying a constant load throughout the year.

Type B Cables carrying varying loads, maximum in summer period.

Type C Cables carrying varying loads, maximum in winter period.

With knowledge of the type of load to be imposed on the cable it is then possible to determine the soil thermal resistivity along thecable route in accordance with recommendations in ERA Report 69-30.

Table 2

Table 3

Ground temperature 15˚C 20˚C 25˚C 30˚C 35˚C 40˚C 45˚C

XLPE Insulated 1.0 0.97 0.93 0.89 0.86 0.82 0.76

Cable Type Rating factor

Size of cables

mm2

Single core cablesUp to 150From 185 to 300From 400 to 1000

Multicore cablesUp to 16From 25 to 150From 185 to 500

1.161.171.17

1.121.121.12

1.071.071.07

0.910.910.91

0.810.800.80

0.730.730.73

0.660.660.66

1.121.141.15

1.081.101.10

1.051.061.07

0.930.920.92

0.840.820.81

0.770.750.74

0.720.690.67

Soil thermal resistivity in ˚C m/W

0.8 0.9 1.0 1.5 2.0 2.5 3.0

B I C C12

Rating factors for depth of laying (to centre of cable or trefoilgroup of cables)

Group rating factors for circuits of three single core cables intrefoil or laid flat touching, in horizontal formation

Table 4

Table 5

Depth of laying

m

0.500.600.801.001.251.501.752.002.503.00

or more

1.000.990.970.950.940.930.920.910.900.89

1.000.980.960.930.920.900.890.880.870.85

1.000.970.940.920.890.870.860.850.840.82

--

1.000.980.960.950.940.920.910.90

--

1.000.970.950.930.910.890.880.86

Up to 50mm2

600/1000 Volt 1900/3300 Volt

70mm2

to 300mm2Above 300mm2 Up to 300mm2 Above 300mm2

Number of Circuits

600/1000Volt cables

1900/3300Volt cables

23456

0.780.660.610.560.53

0.780.660.590.550.52

0.800.680.620.580.55

0.820.710.650.610.58

0.860.770.720.680.66

0.890.800.770.740.72

0.910.830.800.780.76

0.810.700.640.600.57

0.830.730.680.640.61

0.880.790.730.730.71

0.910.840.810.790.78

0.930.870.850.850.82

23456

Spacing of Circuits

Touching +

Trefoil Laid flat 0.15 m* 0.30 m 0.545 m 0.60 m

* This spacing will not be possible for some of the larger diameter cables.

+ For high current carrying cables (i.e. large size) it is advisable to allow spacing between circuits. Alternatively the mostappropriate group rating factor must be applied when determining the cable size and required number of cables in parallel.

SPACINGSPACING

13B I C C

SPACING

Group rating factors for multicore cables in horizontal formation

Recommended duct dimensions and cable sizes

Table 6

Table 7

Number of Cables in Group

Overall cable diameter

mm

Up to and including 65

Above 65 up to and including 90

100

125

130

160

Inside diametermm

Outside diametermm

Spacing

Duct

Touching+ 0.15 m 0.30 m 0.45 m 0.60 m

600/1000volt cables

1900/3000volt cables

23456

0.810.700.630.590.55

0.870.780.740.700.68

0.910.840.810.780.77

0.930.880.860.840.83

0.950.900.890.870.87

23456

0.800.680.620.570.54

0.850.760.710.660.64

0.890.810.770.730.71

0.910.840.810.780.77

0.930.870.840.820.81

CABLES INSTALLED IN DUCTS


The term ducts applies to single way earthenware, fibre or ferrous pipes.

Ratings for cables installed in single way ducts, underground, have been based on values of soil temperature and soil thermalresistivity which are generally representative of conditions in the United Kingdom. Rating factors to take account of variations inground temperatures are given in Table 3. Where conditions of operation can be fairly accurately estimated, and knowledge of thesoil along the route is available, it is possible to determine the ratings more precisely by the use of estimated maximum groundtemperature, the soil thermal resistivity factors, grouping factors, and factors for the depths of laying given in Tables 8 to 11.

Rating factors for ground temperature

Note: Same as for direct in ground, refer to Table 2.

B I C C14

Rating factors of variation in thermal resistivity of soil(average values)

Table 8

Size of cablemm2

Single Core CableUp to 150From 185 to 300From 400 to 1000

Multicore CablesUp to 16From 25 to 150From 185 to 500

Soil thermal resistivity in ˚C m/W

0.8

1.101.111.12

1.041.061.07

1.071.081.08

1.031.041.05

1.041.051.05

1.021.031.03

0.940.930.93

0.970.950.95

0.860.850.84

0.920.900.88

0.800.790.78

0.880.850.83

0.760.750.74

0.860.810.78

0.9 1.0 1.5 2.0 2.5 3.0

Rating factors of depth of laying (to centre of ductor trefoil group of ducts)

Table 9

Depth in laying

m

0.500.600.801.001.251.501.752.002.503.00

or more

1.000.980.950.930.910.890.880.870.860.85

1.000.990.980.960.950.940.940.930.920.91

--

1.000.980.950.930.920.900.890.88

--

1.000.990.970.960.950.940.930.92

600/1000 Volt 1900/3300 Volt

Single Core Multicore Single Core Multicore

Group rating factors for single core cables in trefoilsingle way ducts, horizontal formation (average values)

Table 10

Number of Circuits

600/1000Volt Cables

1900/3300Volt Cables

23456

0.870.780.740.700.69

0.850.750.700.670.64

0.880.800.770.740.72

0.900.830.800.780.76

0.910.840.810.790.78

0.930.870.850.830.82

23456

Spacing

Touching + 0.45 m 0.60 m

SPACING


B I C C 15

Group rating factors for multicore cables in single way ducts,horizontal formation (average values)

Rating factors for other ambient air temperatures

Table 11

Table 12

Number of Ductsin Ground

Spacing

Touching + 0.30 m 0.45 m 0.60 m

600/1000volt cables

1900/3000volt cables

23456

0.900.830.790.750.73

0.880.800.760.720.69

0.910.850.810.780.76

0.930.880.850.830.81

0.940.900.880.860.85

0.930.880.850.830.82

0.950.910.890.880.87

0.960.930.920.910.90

23456

SPACING


It is anticipated that many of the “in air” installations will be in buildings, and the ratings are therefore given in accordance with IEEWiring Regulations for Electrical Installations, 16th Edition.

It should be noted that all ratings for cables run in free air have been based on the assumption that they are shielded fromthe direct rays of the sun without restriction of ventilation. The rating for cables subjected to direct sunlight should bereduced to take account of this factor and further guidance on this subject is available on request.

Defined conditions of installationThe ‘in-air’current ratings given in relevant Tables between 18 to 34 are based on the installation conditions in air as follows:(a) Single core cables

(1) Two single core cables are installed one above the other, fixed to the vertical surface of a wall or open cable trench, the distance between the wall and the surface of the cable being not less than 20mm.

Cables are installed at a distance between centres of twice the overall diameter of the cable, i.e. 2D, where D = overall diameter of cable.

(2) Three single core cables are installed in trefoil formation, fixed to the vertical surface of a wall or open cable trench, the cables touching throughout and the distance between the wall and the surface of the nearest cable being not less than 20mm.

The cables are assumed to be remote from iron, steel or ferro-concrete, other than the cable supports. Single core armoured cables to be electrically bonded at each end of the run.

(b) Multicore CablesCables of all types other than single core cables are installed singly, fixed to the vertical surface of a wall or open cable trench,the distance between the surface of the cable and the wall being not less than 20 mm in every instance.

If it is necessary for cables to be installed at distances less than those described above, then the values tabulated under the heading“Clipped direct to a surface...” in the IEE Wiring Regulations should be employed.

CABLES INSTALLED IN AIR

Air Temperature

XLPE Insulated

25˚C

1.04 1.0 0.96 0.91 0.87 0.82 0.76

30˚C 35˚C 40˚C 45˚C 50˚C 55˚C

B I C C16

Table 13

SHORT CIRCUIT RATINGS – CONDUCTORS

Copper Conductors

Aluminium ConductorsThe values of fault current given in the graph are based on thecable being fully loaded at the start of the short circuit (conductortemperature 90˚C) and a final conductor temperature of 250 ˚C.It should be ensured that the accessories associated with thecables are also capable of operation at these values of faultcurrent and temperature.

Note: With XLPE cables the use of soldered type connectors(instead of the compression type) is not recommended since theiruse in the system would limit the final conductor temperature to160 ˚C (and consequently reduce the fault current rating byapproximately 30 per cent).

Conductor size Short circuit ratings for 1 second in KAmm2 Copper conductor Aluminium Conductor

1.5 0.21 0.142.5 0.36 0.244 0.57 0.386 0.86 0.56

10 1.43 0.9416 2.29 1.5025 3.58 2.3535 5.00 3.2950 7.15 4.7070 10.01 6.5895 13.59 8.93

120 17.16 11.28150 21.45 14.10185 26.46 17.39240 34.32 22.56300 42.90 28.20400 57.20 37.60630 90.09 59.22800 114.40 75.20

1000 143.00 94.00

Note:For any other duration ‘t’seconds divide the givenvalue by √t

0.5

0.1

B I C C

SHORT CIRCUIT RATINGS – ARMOUR

XLPE INSULATED CABLES

Armour Fault currents to earth (for a fault duration of 1 second) Table 14

NominalArea of

Conductor

mm2

16

253550

7095

120

150185240

300400500

630800

1000

Aluminium Wire Armour Steel Wire Armour

600/1000 V 1900/3300 V600/1000 V

Single Core

amp

Single Core

amp

Two Core

amp

Three Core

amp

Four Core

amp

Four Core(reduced neutral)

amp

Three Core

amp

XLPE

-

--4000*

4700*5200*5700*

640071007900

88001240013800

154002130023400

XLPE

-

--4700*

5200*5700*6100

640071007800

85001200013300

14900--

XLPE

1800

190028003100

36005100

-

---

---

---

XLPE

2000

280032003500

410058006400

92001010011500

12300--

---

XLPE

2200

320036004100

600067009400

105001170013200

146002070022500

---

XLPE

-

320034003900

590066007500

100001150012800

139002070022500

---

XLPE

3700

420047005600

620069009400

101001080011900

13000--

---

1900/3300 V

* Based on wire diameters larger than those specified in BS 5467. Refer to Table 17, 33 and 35 for single core cable armour wirediameter

Notes: 1. The ratings given in the Table above are based on a fault duration of one second and an armour temperature rise from 80˚C at commencement of the fault to a final temperature of 200˚C.

2. The asymmetrical fault rating of the smaller sizes may be decided by the short circuit capability of the conductor rather than the armour rating. It is therefore necessary to compare the two ratings.

17

B I C C18

B I C C 19

CONTRIBUTION BY CABLE TO EARTH FAULT LOOP IMPEDANCE

Copper conductor, XLPE insulated armoured cables to BS 5467/BS6724

Table 16600/1000 V

Conductor

mm2

16

253550

7095

120

150185240

300400

6.67

5.874.023.55

2.982.11

-

---

--

6.42

4.353.773.17

2.731.981.79

1.231.100.97

0.89-

5.91

4.103.392.92

1.981.731.25

1.100.980.86

0.780.60

-

4.103.523.05

2.101.731.49

1.141.000.88

0.810.72

2 core

Contribution by cable to earth fault loop impedance milli ohms/metre

4 core3 core4 core

(with reduced neutral)

The following table gives the estimated impedance of copper phase conductor and steel wire armour in series, i.e. thecontribution to earth fault loop impedance by the cable, allowing for the estimated increase in temperature due to theflow of the earth fault current. The earth fault current is taken to be that which gives interruption in 5 seconds whenthe protective device is a standard type having a rating not higher than the current rating of the cable.

Note: For information on maximum length of cable that meets the earth fault loop impedance requirement for 5 seconddisconnection, refer to Ducab’s Technical Department.

B I C C20

XLPE INSULATED CABLES TO BS 5467

DIMENSIONS AND WEIGHTS

STRANDED COPPER & ALUMINIUM CONDUCTORS –SINGLE CORE CABLES

600/1000 V Table 17†Unarmoured and armoured, PVC sheathed cables

Nominalarea of

conductor

mm2

507095

120150185240300400500630800

1000

1.01.11.11.21.41.61.71.82.02.22.42.62.8

14.216.218.320.222.424.727.730.634.238.042.947.853.0

250330430510630760970

119015001900242031203780

540760

1020127015601930251031203970498064008210

10275

12.614.516.418.019.822.024.627.331.236.040.045.850.8

1.6*1.6*1.6*1.6*1.61.61.61.62.02.02.02.52.5

18.420.222.324.227.430.032.835.640.544.248.855.460.6

460560690800970

11501380164021302610318042305000

800990

1280155019002320293035804600568071609315

11490

Thicknessof

insulation

mm

Cablediameteroverall

mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Diameterunder

armour

mm

Armour⊗

wirediameter

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Unarmoured Cables (approximate values) Armoured Cables (approximate values)

† Single core unarmoured cables are as per BS 7889.* Wire diameters are larger than those specified in BS 5467.⊗ Aluminium wire armour for AC system.

B I C C 21

Stranded Aluminium Conductors

600/1000 V

507095

120150185240300400500630800

1000

235290345390435490560630700770840888942

235280330370405440500550580620670692735

222285346402463529625720815918

102711191214

0.870.620.470.390.330.280.240.210.200.180.170.170.16

0.930.700.560.480.430.390.350.320.300.280.260.250.24

0.870.620.470.390.330.280.240.210.200.180.170.170.16

175220260295330375435490540580630

180220260295330365410455480510540

162207252292337391465540625714801

1.400.980.720.580.480.390.310.270.350.310.28

1.601.000.790.660.570.490.420.380.380.350.32

1.400.980.740.600.490.410.340.290.250.220.20

Table 18

CURRENT RATINGS (AC)

Stranded Copper Conductors

Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Current Ratings Current RatingsApproximate voltage drop perampere per metre

Approximate voltage drop perampere per metre

Direct in ground – Trefoil touchingSingle way ducts - ducts touchingSpacing in air - As shown above (D = Cable diameter)

Installation conditions for above ratings:Ambient air temperature:30˚CGround temperature: 15˚CDepth of laying:0.5 mSoil thermal resistivity: 1.2˚C m/WMaximum conductor operating temperature at rated current is 90˚CFor rating factors see Tables 2 to 6 and 8 to 12

Aluminium Conductors

600/1000 V

507095

120150185240300400500630800

1000

230285335385435490570650740840960

11201300

240295345395445500580650750850960

11301320

209270330385445511606701820936

106912141349

0.850.610.450.360.310.260.220.190.170.160.150.150.14

0.930.700.560.480.430.390.350.320.300.280.260.250.24

0.870.610.450.370.310.260.220.200.180.160.150.150.14

175215255295325370430490550620690

180220260300335375440510570640730

159206253296343395471544638743849

1.400.980.710.570.470.390.310.260.360.330.28

1.501.100.790.660.570.490.420.380.380.350.32

1.450.980.730.590.470.390.320.270.230.200.19

Table 19


Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Current Ratings Current RatingsApproximate voltage drop per

ampere per metreApproximate voltage drop per

ampere per metre

STRANDED COPPER & ALUMINIUM CONDUCTORS –SINGLE CORE CABLES

Armoured PVC sheathed cables

Unarmoured PVC sheathed cables

3D 3D

3D3D

B I C C22



600/1000 V Table 20Unarmoured and armoured, PVC sheathed cables

Nominalarea of

conductor

mm2

16*25*35*507095

120150185240300

0.70.90.91.01.11.11.21.41.61.71.8

17.020.222.520.423.126.528.431.735.140.344.3

415480497690850

11701450181022802760

475740955

11001520205026103220403052006430

15.218.521.518.721.524.626.829.733.338.142.3

1.251.251.601.601.602.002.002.002.502.502.50

20.424.127.725.829.033.136.139.344.749.053.5

915125514301780195024403050369043805100

9001240171018002320315038804820592073008770

Thicknessof

insulation

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Diameterunder

armour

mm

Armourwire

diameter

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km


STRANDED COPPER & ALUMINIUM CONDUCTORS –TWO CORE CABLES

* Circular conductor, all others are sector shaped

Note: Unarmoured cables are as per IEC 60502 (Part 1)

B I C C 23


600/1000 V

16*25*35*507095

120150185240300

140180215255315381410472539636732

115145175210260313344384432504560

115152188228291354430480540630700

2.91.91.31.00.70.50.40.40.30.20.2

2.91.91.31.00.70.50.40.40.30.20.2

2.91.91.31.00.70.50.40.40.30.20.2

135165195240288

110130155195237

112138166211254

3.12.21.71.10.8

3.12.21.71.10.8

3.12.21.71.10.8

Table 21



Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV




600/1000 V

16*25*35*507095

120150185240300

140180215255315380410473542641741

115140170205255311344384432504560

115149185225289352430480540630700

2.91.91.31.00.70.50.40.40.30.20.2

2.91.91.31.00.70.50.40.40.30.20.2

2.91.91.31.00.70.50.40.40.30.20.2

135165195240285

105130150195235

108135164211257

3.12.21.71.20.8

3.12.21.71.20.8

3.12.21.71.20.8

Table 22Stranded Copper Conductors

Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV



STRANDED COPPER & ALUMINIUM CONDUCTORS –TWO CORE CABLES



Direct in ground – Cables touchingSingle way ducts - ducts touching* Circular conductors, all others are sector shapedNote: (1) 50 mm2 and above are with D-shaped conductor

(2) Unarmoured cables are as per IEC:60502 (part 1)


* Circular conductor, all others are sector shaped

B I C C24



600/1000 V Table 23

Nominalarea of

conductor

mm2

16*25*35*507095

120150185240300400

0.70.90.91.01.11.11.21.41.61.71.82.0

18.021.524.024.628.031.034.838.544.049.553.559.2

500610740

10501170144023002750302036603730

675990

12951640222029803730519564708380

1042011575

16.020.022.723.026.030.032.836.841.546.051.556.4

1.251.61.61.61.62.02.02.52.52.52.52.5

21.626.729.428.532.237.040.445.549.855.160.266.6

12201415155018102500287036604320517061007050

113017102100245031204310516071608600

107551308015810

Thicknessof

insulation

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Diameterunder

armour

mm

Armourwire

diameter

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km


STRANDED COPPER & ALUMINIUM CONDUCTORS –THREE CORE CABLES

Unarmoured and armoured, PVC sheathed cables

* Circular conductors, all others are sector shaped.


B I C C 25


600/1000 V

162535507095

120150185240300400

115150180215265315360405460530590667

94125150175215260300335380440495570

99131162197251304353406463546628728

2.51.71.20.90.60.50.40.30.30.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.2

89115135165200240275310350410460520

7294

110135165200230255295340385443

7498

120145185224264305350418488562

4.22.71.91.41.00.70.60.50.40.30.30.2

4.22.71.91.41.00.70.60.50.40.30.30.2

4.22.71.91.41.00.70.60.50.40.30.30.2

Table 24



Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV



Direct in ground – Cables touchingSingle way ducts - ducts touchingNote: Unarmoured cables are as per IEC 60502 (Part 1)


Stranded Copper Conductors Stranded Aluminium Conductors

600/1000 V

162535507095

120150185240300400

120145180215265315365405465540600675

93125145175215255300330380440500575

100127158192246298346399456538621741

2.51.71.20.90.60.50.40.30.30.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.2

115135165200240275310350415465523

92110135165195225255290340385443

97120146187227263304347409471570

2.71.91.41.00.70.60.50.40.30.30.2

2.71.91.41.00.70.60.50.40.30.30.2

2.71.91.41.00.70.60.50.40.30.30.2

Table 25

Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV



STRANDED COPPER & ALUMINIUM CONDUCTORS –THREE CORE CABLES



B I C C26




Nominalarea of

conductor

mm2

16*2535507095

120150185240300400

500#

0.70.90.91.01.11.11.21.41.61.71.82.02.2

20.021.024.526.531.035.239.043.549.054.561.067.574.2

-520650900

121015501910241029903890473057807500

78011601540210029503970496061607690

10070124901562019900

18.020.022.825.529.533.537.541.546.052.557.565.072.6

1.251.61.61.62.02.02.52.52.52.52.53.153.15

23.426.128.632.037.741.747.151.456.663.068.878.182.0

-1200142017702500298039504600543066607770

1038012200

13201840231029704240540070008350

1013012840155301995024360

Thicknessof

insulation

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Diameterunder

armour

mm

Armourwire

diameter

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km


STRANDED COPPER & ALUMINIUM CONDUCTORS –FOUR CORE CABLES

* Circular conductors, all others are sector shaped.# Cable as per IEC 60502 (Part 1)


B I C C 27

Direct in ground – Cables touchingSingle way ducts - ducts touchingNote: Unarmoured cables are as per IEC 60502 (Part 1)

Installation conditions for above ratings:Ambient air temperature: 30˚CGround temperature: 15˚CDepth of laying: 0.5 mSoil thermal resistivity: 1.2˚C m/WMaximum conductor operating temperature at rated current is 90˚CFor rating factors see Tables 2 to 6 and 8 to 12

Stranded Copper Conductors Aluminium Conductors

600/1000 V

162535507095

120150185240300400500

120145180215265315365405465540600675730

93125145175215255300330380440500575610

100127158192246298346399456538621741814

2.51.71.20.90.60.50.40.30.30.20.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.20.2

89115135165200240275310350415465523565

7292

110135165195225255290340385443470

7497

120146187227263304347409471570626

4.22.71.91.41.00.70.60.50.40.30.30.20.2

4.22.71.91.41.00.70.60.50.40.30.30.20.2

4.22.71.91.41.00.70.60.50.40.30.30.20.2

Table 28Unarmoured PVC sheathed cables

Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV




600/1000 V

162535507095

120150185240300400500

115150180215265315360405460530590667720

94125150175215260300335380440495570605

99131162197251304353406463546628728800

2.51.71.20.90.60.50.40.30.30.20.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.20.2

2.51.71.20.90.60.50.40.30.30.20.20.20.2

89115135165200240275310350410460520561

7294

110135165200230255295340385443470

7498

120145185224264305350418488562618

4.22.71.91.41.00.70.60.50.40.30.30.20.2

4.22.71.91.41.00.70.60.50.40.30.30.20.2

4.22.71.91.41.00.70.60.50.40.30.30.20.2

Table 27



Nominalarea of

conductormm2

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV

Direct ingroundamps

In singleway ducts

amps

Installedin airamps

Ground

mV

Duct

mV

Air

mV



ampere per metre

STRANDED COPPER & ALUMINIUM CONDUCTORS –FOUR CORE CABLES


B I C C28




Nominalarea of

conductor

mm2

Nominalarea ofneutral

conductormm2

2535507095

120150185240300400

500#

16*16*25*355070

70*95

120*150*185*240*

0.90.91.01.11.11.21.41.61.71.82.02.2

21.423.226.130.434.839.442.547.753.459.067.074.0

--

860108013901820219026303500424055606700

107013601920261035004540544067608900

110001390017560

19.122.024.528.532.035.539.543.550.255.062.568.8

1.61.61.62.02.02.02.52.52.52.53.153.15

26.127.931.236.641.045.350.055.361.166.773.883.9

--

171023402800334043605020622072209950

11200

17502130277038704910606076109150

11620139801825022000

Thicknessof

insulation(phase)

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km

Diameterunder

armour

mm

Armourwire

diameter

mm


mm

Cableweight

Aluminium

kg/km

CableweightCopper

kg/km


STRANDED COPPER & ALUMINIUM CONDUCTORS –FOUR CORE CABLES WITH REDUCED NEUTRAL CONDUCTOR

* Circular stranded conductors, all others are sector shaped.# Cable as per IEC 60502 (Part 1)


B I C C

Nominalarea of

conductor

mm2

29

600/1000 V

2535507095

120150185240300400500

16*16*25*

355070

70*95

120*150*185*240*

150180215265315360405460530590667720

125150175215260300335380440495570605

131162197251304353406463546628728800

1.71.20.90.60.50.40.30.30.20.20.20.2

1.71.20.90.60.50.40.30.30.20.20.20.2

1.71.20.90.60.50.40.30.30.20.20.20.2

115135165200240275310350410460520561

94110135165200230255295340385443470

98120145185224264305350418488562618

2.71.91.41.00.70.60.50.40.30.30.20.2

2.71.91.41.00.70.60.50.40.30.30.20.2

2.71.91.41.00.70.60.50.40.30.30.20.2

Table 30



Nominalarea of

conductor

mm2


conductor

mm2

Direct inground

amps

In singleway ducts

amps

Installedin air

amps

Ground

mV

Duct

mV

Air

mV

Direct inground

amps

In singleway ducts

amps

Installedin air

amps

Ground

mV

Duct

mV

Air

mV



Direct in ground – Cables touchingSingle way ducts - ducts touching* Circular conductors, all others are sector shapedNote: Unarmoured cables are as per IEC 60502 (Part 1)


600/1000 V Table 31Unarmoured PVC sheathed cablesStranded Copper Conductors Stranded Aluminium Conductors

2535507095

120150185240300400500

16*16*25*355070

70*95

120*150*185*240*

145180215265315365405465540600675730

125145175215255300330380440500575610

127158192246298346399456538621741814

1.71.20.90.60.50.40.30.30.20.20.20.2

1.71.20.90.60.50.40.30.30.20.20.20.2

1.71.20.90.60.50.40.30.30.20.20.20.2

115135165200240275310350415465523565

92110135165195225255290340385443470

97120146187227263304347409471570626

2.71.91.41.00.70.60.50.40.30.30.20.2

2.71.91.41.00.70.60.50.40.30.30.20.2

2.71.91.41.00.70.60.50.40.30.30.20.2


conductor

mm2

Direct inground

amps

In singleway ducts

amps

Installedin air

amps

Ground

mV

Duct

mV

Air

mV

Direct inground

amps

In singleway ducts

amps

Installedin air

amps

Ground

mV

Duct

mV

Air

mV



ampere per metre

STRANDED COPPER & ALUMINIUM CONDUCTORS –FOUR CORE CABLES WITH REDUCED NEUTRAL CONDUCTOR

Stranded Copper Conductors Stranded Aluminium Conductors

* Circular conductors, all others are sector shaped.

B I C C

999793898480746862

16

265260250245235225215205195

115112110105100

97948984

70

251240230220210195185170150

0.6070.5990.5890.5800.5720.5620.5540.5450.536

185

463450430415395370345320290

0.2550.2520.2490.2460.2430.2400.2370.2350.232

460450435420405390375355335

2.502.502.472.432.392.352.312.272.23

Currentin ground

A

Voltagedrop

mV/A/m

Currentin air

A

Conductorsizemm2

215210200195190185175165155

0.8650.8520.8390.8260.8130.8000.7870.7740.761

197190180175165155145135120

50 150

406395375365345325305280250

0.3030.2990.2950.2920.2880.2840.2800.2770.273

405395385370360345330315295

400

728715685655620585545500450

0.1660.1630.1620.1610.1600.1590.1580.1570.156

667640620600580560535505475

315305300290280270255245230

150145140135130125120115110

25

131130125120110105999182

1.651.591.561.541.511.491.461.441.41

95

304295290270255240225210190

0.4460.4390.4330.4270.4210.4150.4080.4020.396

240

546530510490465440410375340

0.2110.2080.2060.2040.2030.2000.1990.1970.195

530515500485470450430410385

180175170165160150145140130

35

162155150145135130120110100

1.151.151.131.111.091.081.061.041.02

120

353340325310300280260240215

0.3660.3570.3520.3470.3420.3370.3330.3280.323

360350340330320305295280260

300

628605580555530500465430390

0.1850.1830.1810.1800.1790.1770.1760.1740.174

590575560540520500480455430

Currentin ground

A

Voltagedrop

mV/A/m

Currentin air

A

Conductorsizemm2


CURRENT RATINGS (AC) AND VOLT DROPS

STRANDED COPPER CONDUCTORSThree and four core armoured, PVC sheathed cables

Installation conditions for above ratings:Ambient temperature:30˚CGround Temperature: 15˚C

Soil Thermal resistivity:1.2˚Cm/WDepth of laying: 0.5m

600/1000 V Table 32Conductor

sizemm2

Currentin air

A

Voltagedrop

mV/A/m

Currentin ground

A

30

B I C C 31



Stranded Copper Conductors - Single core cables

Stranded Copper Conductors - Single core cables

Stranded Copper Conductors - Three core cables

1900/3300 V Table 33Armoured PVC Sheathed Cables

Approximate Values

Nominalarea of

conductormm2

Thicknessof

insulationmm

Thicknessof

insulationmm

Diameterunder

armourmm

Diameterunder

armourmm

Armour^wire

diametermm

Armourwire

diametermm


mm


mm

Cableweightcopperkg/km

Cableweightcopperkg/km

Nominalarea of

conductormm2

Approximate Values

507095

120150185240300400500630800

1000

2.02.02.02.02.02.02.02.02.02.22.42.62.8

15.016.618.419.821.223.025.527.731.036.040.045.850.8

1.6*1.6*1.6*1.61.61.61.61.62.02.02.02.52.5

20.622.424.327.228.830.833.536.140.544.248.855.460.6

81010401330168019702370296036104600568071609150

11270

16+25+35+507095

120150185240300

--

2.02.02.02.02.02.02.02.02.02.02.0--

21.524.526.525.228.431.036.638.542.547.851.4

--

1.61.61.62.02.02.02.52.52.52.52.5--

29.332.234.834.738.041.445.748.551.956.961.2

--

160020602400320038004730607070108270

1031012300

--

CURRENT RATINGS

Stranded Copper Conductors - Three core cables

1900/3300 V Table 34

Nominalarea of

conductormm2

Nominalarea of

conductormm2

Direct inground

amps

Direct inground

amps

In singleway ducts

amps

In singleway ducts

amps

Installed inair

amps

Installed inair

amps

507095

120150185240300400500630800

1000

222271324366409460528589651720789831880

219264310342376414464506535579624650689

228285350407463528623710808915

103011191214

162535507095

120150185240300

--

114147175207254304345387436502563

--

96124147174214257293328371428480

--

106142168202255312361410471554634

--

Direct in ground – Trefoil touchingSingle way ducts - ducts touchingSpacing in air - As shown above (D=Cable diameter)*Wire diameters are larger than those specified in BS 5467^Aluminium wire armour for AC system

Installation conditions for above ratings:Ambient air temperature: 30˚CGround temperature: 15˚CDepth of laying: 0.5 mSoil thermal resistivity: 1.2˚C m/WMaximum conductor operating temperature at rated current is 90˚CFor rating factors see Tables 2 to 6 and 8 to 12

Armoured PVC Sheathed Cables

+ Circular conductors, all others are sector shaped

B I C C32

600/1000 V Table 35

XLPE INSULATED CABLES TO BS 5467DIMENSIONS AND WEIGHTS

Lead Sheathed Armoured Power Cables to BS 5467 and EEMUA 133

50*70*95*

120*150185240300400500630800

1000

1625

35+507095

120150185240300

162535

50+7095

120150185240300400

1625+

35507095

120150185240300400

13.015.016.818.520.522.825.528.132.337.040.847.552.5

15.518.921.319.022.224.827.230.333.738.942.9

16.520.523.024.026.530.533.537.842.848.252.257.8

18.820.523.226.230.534.837.843.247.853.858.565.9

1.61.61.61.61.61.61.61.62.02..02.02.52.5

1.251.251.61.61.62.02.02.02.52.52.5

1.251.61.61.61.62.02.02.52.52.52.52.5

1.251.61.61.62.02.02.52.52.52.52.53.15

20.822.624.526.228.530.833.536.441.846.650.859.264.2

21.825.529.427.230.534.537.841.146.351.756.3

23.028.631.232.035.040.543.549.454.560.265.271.8

25.528.531.334.640.544.849.855.060.066.572.582.6

13001620204023802840336541805060640080009720

1270015400

1540206026702640340045305170612077109650

11510

17502650322036304560611073008980

10870135001615019550

2120280034304260585073409400

1128013600170002015026100

Nominalarea of

conductor

mm2

Nominal lead sheaththickness

mm

Overlead

mm

ArmourWire

mm

Overallcable

mm

Approx. weight

kg/km

Approximate diameter

* Cable with 1.6mm wire armour, a deviation from BS 5467.Tolerance on the above dimensions are -0.3mm and +0.5mm.Cable sizes marked + and higher have sector shaped conductors.

Lead sheath thicknesses are nominal values based on EEMUA 133.For 2 core cables, 50 mm2 and above have D-shaped conductors.

1.11.11.11.21.21.31.41.41.61.71.82.02.1

1.11.21.31.21.31.41.41.51.61.81.9

1.11.21.31.31.41.51.61.71.92.02.22.3

1.21.21.31.41.51.61.71.92.02.22.32.5

B I C C 33

1900/3300 V Table 37

RESISTANCE OF LEAD SHEATH AND ARMOUR


Nominal area ofconductor

mm2

Single coreLead Armour

1.52.5

46

10162535507095

120150185240300400500630800

1000

-----

8.146.636.015.244.564.073.303.032.482.031.861.411.160.980.760.65

8.987.566.375.854.914.293.212.603.192.522.101.891.581.331.020.87

----

6.215.514.884.594.013.102.641.691.881.641.141.040.950.690.610.55

----

8.547.096.275.404.714.112.962.412.371.951.601.321.130.890.760.620.53

----

5.965.264.814.312.932.641.581.421.401.270.870.780.580.520.470.420.39

----

7.726.295.414.914.103.312.932.381.961.591.301.110.880.750.610.530.43

----

5.594.844.313.022.632.361.571.411.270.870.770.570.510.470.420.380.26

----

-----

2.421.971.681.611.541.371.101.000.860.730.610.53

----

-----

1.371.221.130.840.810.770.540.520.480.430.400.37

----

-----

0.620.540.500.470.420.390.350.320.290.260.240.170.150.130.090.08

Two coreLead Armour

Three coreLead Armour

Four coreLead Armour

Three coreLead Armour

600/1000 V 1900/3300 V

Maximum Resistance (ohms) per 1000 metres of cable at 20˚C

Note: Single core cables with Aluminium Wire Armour and Multicore cables with Steel Wire Armour


1900/3300 V Table 36

XLPE INSULATED CABLES TO BS 5467DIMENSIONS AND WEIGHTS


162535

50+7095

120150185240300

22.926.128.629.831.132.738.039.843.848.953.3

1.61.61.62.02.02.02.52.52.52.52.5

31.834.937.640.241.743.550.452.756.662.366.9

27503412404548225560658284409540

112721381916456

Nominalarea of

conductor

mm2

Nominal lead sheaththickness

mm

Overlead

mm

ArmourWire

mm

Overallcable

mm

Approx. weight

kg/km

Approximate diameter

+ Cable sizes 50 mm2 and higher have sector shaped conductors.

1.31.41.51.51.51.61.71.81.92.02.2

B I C C34

Ducab can manufacture a dedicated cable called LSF (Low Smoke and Fume) for installations where fire and its associated problems- the emission of smoke and toxic fumes - offer a serious potential threat. LSF compound is free from halogens (fluorine, chlorineand bromine) and when tested to BS 6425 Part 1 and IEC 754 Part 1 the acidic gas evolved during combustion is less than 0.5% byweight of material. Furthermore, when tested in accordance with BS 2782 Method 141D, the oxygen index of both bedding andsheath will not be less than 30. These cables comply with BS 6724 and also meet the requirements of IEC 332 Part 3.

LSF Cable:

● is slow to ignite,burns slowly and gives off reduced smoke and fumes which can kill people● does not produce corrosive halogen acid gases which destroy sensitive electronic equipment ● helps people to escape from a fire - helps them to see and to breathe for longer● wins time for people to escape and for emergency services to help● is essential in public buildings, transport or confined areas where larger numbers of people - many of them strangers to the

surroundings or infirm - regularly congregate

Some of the key benefits of LSF cables are as follows:

... to the Public● much improved safety margins to help them survive a fire situation in enclosed areas or high population, high-tech commercial

offices in which they might work or visit

... to the Specifier● enhanced fire damage protection for both structure and sensitive electronic equipment● demonstrates proper concern for public and environmental safety

... to the Contractor

● no loss of versatility● can be installed wherever conventional cables would be used and are compatible with standard accessories

LSF cables should be used in any location where the outbreak of fire would constitute an immediate threat to life and to theperformance of sensitive electronic equipment.

LSF cables with their slow burning and no-smoke qualities are most essential in ‘high population’public or commercial buildings,enclosed areas such as tunnels or public transport, or places where large numbers of people, perhaps unfamiliar with theirsurroundings or with limited mobility, congregate - for example:

- places which are densely occupied on a regular basis - multi storey dwellings, office blocks, hotels, educationalestablishments, factories.

- places where large number of people congregate without being familiar with the layout - cinemas, theatres, shoppingcomplexes, tunnels, underground and surface passenger terminals and concourses.

- for housing people with limited mobility - hospitals, retirement homes.

- places involving high security - defence installations, prisons, research establishments, computer centres

- where operating critical processes - power stations, nuclear reprocessing petro-chemical installations.

Note: For technical data for LSF cables, please refer to Technical Department.

WHICH SITUATIONS DEMAND LSF CABLE?

ADVANTAGES OF XLPE INSULATED CABLES1. Does not soften beyond the normal range of conductor operating temperatures and is called THERMOSETTING insulation. 2. Due to greater capacity to withstand heat, the permissible maximum continuous conductor operating temperature is 90˚C and for

momentary short circuits the permissible temperature is 250˚C.3. Higher insulation strength and superior mechanical properties allow lower insulation thickness. The insulation resistance value

of the cable does not appreciably change with conductor operating temperature. 4. XLPE insulation dissipates heat from conductors much faster as its thermal resistivity is 3.5˚C m/W.5. Heat generation in the insulation itself is low due to very low “loss angle”. 6. Due to the foregoing reasons, an XLPE cable can carry 15% to 30% higher current than a PVC cable with the same conductor

size. 7. Density of XLPE is 0.92 to 0.94 gm/ml and due to lower insulation thickness, XLPE insulated cables are lighter and easier to

install.8. Jointing and terminating of XLPE insulated cables does not require any special techniques.

LSF CABLES

B I C C 35

XLPE CABLE DATA FOR PARTIAL LOADS

The current ratings given in relevant tables of this publication assume that cables are fully loaded i.e. conductor operatingtemperature is 90˚C and conductor resistances at this temperature have been used in the tabulated figures of volt drop perampere per metre for various sizes of cables.

In many situations the conductor size which is ultimately chosen may not be carrying its maximum permissible current (i.e. its fullrated current) and consequently it will not be operating at its maximum designed temperature. Table 32 shows the reduced voltagedrop / ampere/metre/ data corresponding to reduced operating temperature due to reduced load currents. The first line is applicableto 90˚C conductor temperature. Examples are given below to illustrate situations where over-designing can be avoided. “Standardconditions” in the following refer to those obtained in the United Kingdom on which the current rating /voltage drop tables arebased. For situations other than “standard conditions” such as those in the Middle East, suitable rating factors can be applied forutilising data in Table 32 as shown in example (3) in the following:

It should also be ensured that the cable size ultimately selected is capable of carrying the required current under site conditions ofinstallation. Formula Vd = mV x I x L or mV = Vd x 1000

1000 I x Lwhere Vd = maximum acceptable volt drop (in volts)

I = current per phase (in amps)mV = appropriate volt drop (in mV/amp/metre)L = route length (in metres)

Examples: At standard defined conditions:1) Consider a route of 120 metres of four core copper XLPE/SWA/PVC to be installed in air (at standard conditions) and to carry300 amps per phase at 415 volts. Maximum voltage drop to be 2.5 per cent. 2.5 per cent of 415 V = 10.4 VSubstitute for current, route length and maximum volt drop

mV = 10.4 x 1000 = 0.289 mV/A/m300 x 120

From Table 32, the first line of figures per conductor size (corresponding to IEE Wiring Regulations) and giving a voltage dropvalue less than 0.289 is 185 mm 2. By studying the table to find a voltage drop value equal to, or less than the 0.289 calculated, butat the same time representing the 300 A load required, it will be seen that a voltage drop of 0.280 corresponds to a current of 305A and a reduced conductor size of 150 mm2. Therefore it is possible to select a 150 mm2 cable rather than the 185 mm2 cable firstindicated.

The actual volt drop of this installation is Vd = 300 x 120 x 0.280 = 10.1 V

1000

2) Consider a route of 130 metres of four core copper XLPE /SWA/PVC cable to be installed partly in air, partly underground, andto carry 260 amps per phase at 380 V. Maximum voltage drop to be 3 per cent. 3 per cent of 380 V = 11.4 VSubstitute for current, route length and maximum volt dropmV = 11.4 x 1000 = 0.337 mV/A/m

260 x 130

Selecting a voltage drop corresponding to the maximum rating the size would be 150 mm2 but selecting from Table 32 such thatmV/A/m is equal to, or less than the 0.337 calculated and is capable of carrying 260 A (in ground and in air), it will be seen thatthis value is 0.333 for a 120 mm2 cable (instead of 150 mm 2).and the actual voltage drop = 260 x 130 x 0.333 = 11.3 V

1000(See Tables 2 to 12 for site conditions other than standard defined conditions)

Examples: At site conditions other than standard defined conditions3) Consider example (1) but at an ambient temperature of 45˚C. Derating factor for this temp. = 0.87 (see Table 12). Using thisfactor, calculate the ‘equivalent current’at standard conditions by dividing the actual current by the derating factor.Thus ‘equivalent current’ = 300 = 345 A

0.87and from previous example (1) the mV/A/m figure needs to be 0.289 or less. Selecting a cable from Max Rating figures as previously - the cable would be 185 mm2.However selecting from Table 32 with a current of 345A and a volt drop of 0.289 (or less), gives a cable size of 150 mm2 with avoltage drop value of 0.288 mV/A/m at 345A. (instead of the 185 mm2).

and the actual voltage drop = 300 x 120 x 0.288 = 10.4 V1000

For installations where XLPE insulated cables are not fully loaded andconductor operating temperatures are below 90˚C.

B I C C

XLPE INSULATED CABLE TO BS 5467Table 38600/1000 V STRANDED COPPER CONDUCTORS

36

B I C C 37

Dubai Cable Company (Pvt) LtdP O Box 11529DubaiUnited Arab EmiratesTel: (971-4) 808 2500Fax: (971-4) 808 2511email: [email protected]: www.ducab.ae

Advanced Cable Solutions Through Technology and Innovation

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