doble tutorial - medium voltage power cables and accessories

8/17/2019 Doble Tutorial - Medium Voltage Power Cables and Accessories

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TUTORIAL:

MEDIUM VOLTAGE POWER CABLES

AND ACCESSORIES

2011

International

Conference

of

Doble

Clients

Thursday,

March

31,

2011

7:30

AM

–

12:00

PM

Westin

Copley

Place

Hotel

America

North,

4th

Floor


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Doble Client Conference: ICEA Standards Review March 31, 2011

Insulated CableEngineers Association

(ICEA)

Standards Review


I. Overview of ICEA

Energy Division – Power Cable Section

II. Industry Wide Input & Standards Coordination

III. ICEA Cable, Test & Application Standards

That Apply To Power Cables

IV. Navigating The ICEA Website


Overview of ICEA

Composed strictly of engineers who are employed by

cable manufacturing companies.

These companies are sponsors of the association.

Members cannot be involved in sales, pricing or order placement.

IPCEA was formed in 1925 by a group of power cable engineers.

Evolved into 3 separate sections – Control & Instrumentation

Cables, Power Cables & Portable Power Cables.

In 1979 Communication Cables were added and the name was changed

to Insulated Cable Engineers Association (ICEA).


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Overview of ICEA

The organization was later reorganized into two Divisions Energy Cables

Communications Cables

The Energy Cables Division retained

Control & Instrumentation (C&I)

Power

Portable

The Communication Cables Division was further subdivided into

Copper

Fiber


Overview of ICEA

The association meets quarterly in March, June, September

and December.

The association maintains a website at ICEA.net

The association is a “Not-For-Profit” organization who’s sole

support is from member dues & fees and standards sales.

Since 1925 the objective has been to ensure safe, economical

and efficient cable systems utilizing proven state-of-the-art

materials and concepts.


Industry Wide Input & Standards Coordination

The Utility Power Cable Standards Technical Advisory Committee

UPCSTAC was formed in 1996.

Outgrowth of a long felt need for a comprehensive, national

standard for concentric neutral power cable.

UPCSTAC membership is comprised of

ICEA Power Cable Section members

AEIC Cable Engineering Committee members

The primary documents covered by UPCSTAC are for Medium and

High Voltage Utility Power Cables.

The documents are also reviewed by IEEE Insulated Conductors

Committee (ICC) and American National Standards Institute (ANSI)


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Cable, Test & Application Standards for Power Cables

Test Standards



Test Standards include:

ANSI/ICEA T-24-380 Standard for Partial-Discharge Test Procedure

ICEA T-25-425 Guide for Establishing Stability of Volume

Resistivity for Conducting Polymeric Compounds of Power Cables

ANSI/ICEA T-26-465 Guide for Frequency of Sampling Extruded

Dielectric Cables

ANSI/ICEA T-28-562 Test Method for Measurement of Hot Creep

of Polymeric Insulation

ANSI/ICEA T-27-581 Test Methods for Extruded Dielectric Cables



Test Standards include: (continued)

ANSI/ICEA T-31-610 Test Method for Conducting Longitudinal

Water Penetration Resistance Tests on Blocked Conductors

ICEA T32-645 Guide for Establishing Compatibility of SealedConductors with Conductor Stress Control Materials

ICEA T-33-655 Low Smoke, Halogen-Free Polymeric Jackets

ANSI/ICEA T-34-664 Test Method for Conducting Longitudinal Water

Penetration Resistance Tests on Longitudinal Blocked Cables


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Application Standards


Cable, Test & Applications Standards for Power Cables

Application Oriented Standards include:

ANSI/ICEA P-32-382 Short-Circuit Characteristics of Insulated Cable

ICEA P-54-440 Ampacities of Cables in Open-Top Trays

ANSI/ICEA P-45-482 Short-Circuit Performance of Metallic Shields

& Sheaths

ANSI/ICEA P-79-561 Guide for Selecting Aerial Cable Messengers

& Lashing Wires



Non-shielded Cable Standards


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Non-shielded Cable Standards include:

ANSI/ICEA S-76-474 Neutral Supported Power Cable Assemblieswith Weather-Resistant Extruded Insulation Rated 600 Volts

ANSI/ICEA S-70-547 Weather Resistant Polyethylene Covered

Conductors

ANSI/ICEA S-81-570 600 Volt Rated Cables of Ruggedized Design

for Direct Burial Installations as Single Conductors or Assemblies

of Single Conductors



Non-shielded Cable Standards include: (continued)

ANSI/ICEA S-95-658 Non-Shielded Power Cables Rated 2000 V

or Less

ICEA S-96-659 Non-Shielded Power Cables Rated 2001 – 5000 V

ANSI/ICEA S-105-692 600 Volt Single Layer Thermoset Insulated

Utility Underground Distribution Cables



Shielded Cable Standards


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Shielded Cable Standards include:

ANSI/ICEA S-93-639 Shielded Power Cables 5,000 – 46,000 V

ANSI/ICEA S-94-649 Concentric Neutral Cables Rated 5 Through

46 kV

ANSI/ICEA S-97-682 Utility Shielded Power Cables Rated 5

Through 46 kV

ANSI/ICEA S-109-720 Extruded Insulation Power Cables Rated

Above 46 kV Through 345 kV


Working Groups for New Standards

• WG 684 Performance Based Utility 5 – 46 kV

• WG 726 Pellet Inspection Systems

• WG 728 Non-Metallic Shielded Mining Cables

• WG 733 Tree Wire and Spacer Cable

• WG 734 New Electric Distribution Ampacity Tables


Navigating The ICEA Website


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We reorganized the ICEA Web site at http://www.icea.net

to make it easier to find the Standard you need.

• Added a “New & Recently Added Documents” Direct Link

• Separated Energy & Communication Documents

• Divided Energy Documents into:

• Power Cable

• Portable Cable

• Control & Instrumentation (C&I) Cable

• Added a Preview & Purchase Link for Each Document

• Cover, Table of Contents, Scope


About ICEAThe Insulated Cable Engineers Association (ICEA) is a professionalorganization dedicated to developing cable standards for theelectric power, control, and telecommunications industries. Since1925, the objective has been to ensure safe, economical, andefficient cable systems utilizing proven state-of-the-art materialsand concepts. Now with the proliferation of new materials andcable designs, this mission has gained in importance. ICEAdocuments are of interest to industry participants worldwide, i .e.cable manufacturers, architects and engineers, utility andmanufacturing plant personnel, telecommunication engineers,consultants, and OEM'S.

ICEA is a "Not-For-Profit" association whose members aresponsored by over thirty of North America's leading cablemanufacturers. The technical development work is performed infour semi-autonomous Sections; namely, the Power, Control &Instrumentation, Portable, and Communications Cable Sections. In

addition there are currently two very active major TechnicalAdvisory Committees, one for Telecommunications Wire and CableStandards (TWCS TAC) and another Utility Power Cable Standards(UPCS TAC).

INSULATED CABLE ENGINEERS ASSOCIATION, Inc.



ICEA Engineering DocumentsIt is ICEA's mission to keep these standards up-to-date on acontinuing basis. These Documents may be purchased throughIHS.

ICEA Standards fall into four categories:

Refer to our Ordering Info page for purchasing details.

Back


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New & Recently Added Documents

These standards were developed by the Insulated CableEngineers Association, Inc. (ICEA), within the past 3 years. TheseDocuments may be purchased through IHS.

You may view the first pages including the Table of Contents for some documents by clicking on the Preview Documents linkand/or purchase them by clicking on the Purchase Now link. Notall documents have previews available.

Energy Cable Standards

ANSI/ICEAT-24-380-2007Guide For Partial-Discharge Test Procedure$60.00 Preview Document Purchase Now





Energy Documents

Back


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Thanks For Including ICEA

In Your Conference

&

Any Additional Questions


12/109


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1

AEIC Cable EngineeringCommittee Specifications,

and Guides

by Mike Smalley – We Energies, Chair, AEIC Cable Engineering Committee

Doble Conference – March 31, 2011

2

Association of Edison Illuminating

Companies (AEIC)

Established in 1885 by Thomas Edison

Members are electric utilities, generationcompanies, transmission companies, anddistribution companies – internationally.

Through a committee structure, the Associationaddresses technological problems associatedwith planning, building and operating an electricutility system.

3

AEIC (Cont)

Includes investor-owned, federal, state,

cooperative, and municipal systems

Associate members include organizationsresponsible for technical research and for

promoting, coordinating, and ensuring the

reliability and efficient operation of the bulk

power supply system (e.g. EPRI).


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4

AEIC Committees

The AEIC's six committees are staffed withexperts from management of membercompanies and meet regularly during the year toexplore issues in their particular areas: Load Research

Meter and Service

Power Apparatus

Power Delivery

Power Generation

Cable Engineering

5

Cable Engineering Committee (CEC)

28 Members and 2 Technical Advisors

Cable Engineers from Electric Utilities

Engineers from Research Labs and

Organizations

6

CEC Purpose

The purpose of the

CEC is to develop

and maintain

specifications andguides for electric

utility cable system

design, maintenance,

and operations.

7 Specifications

11 Guidelines


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7

CEC Procedures

Goals:

Reaffirm, Revise, or Withdraw specifications every 5years

Reaffirm, Revise, or Withdraw guides every 7 years

A Task Group chair, Vice Chair, and TG

members are assigned to each document

Once complete, documents are balloted within

the task group. After TG approval, the whole

CEC is balloted

8

Outline for All Cable Specs

Conductor

Conductor Shield

Insulation

Insulation Shield

Metallic Shielding

Moisture Barrier

Jacket

9

Outline for All Cable Specs (Cont)

Cable Identification

Production Test Procedures

Shipment and Reels

Guarantee

Tests During and After Installation


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10

CEC Paper (Laminar) Cable Specs

These Specifications are considered to be theindustry standard (there is no NEMA, ANSI orICEA cable standard associated with them): CS1-90 PILC

CS2-97 High Pressure Pipe Type

CS3-90 Low Pressure Gas-Filled Type

CS4-93 Low and Medium Pressure Self-ContainedLiquid Filled Cable

CS31-95 Pipe Filling Liquids

11

CEC Extruded Dielectric Cable Specs

CS5, Obsolete, replaced by CS8

CS6, Obsolete, replaced by CS8 and CS9

CS7, Obsolete, replaced by CS9

CS8-07 Extruded Dielectric 5-46 kV, supplements: NEMA WC74/ICEA S-93-639 (Shielded Power Cables 5-46 kV)

ICEA S-94-649 (Medium Voltage CN cables)

ICEA S-97-682 (Utility Shielded Power Cables 5-46 kV)

CS9-06 Extruded Dielectric Cables and Their Accessories Rated Above 46 kV through345 kV AC, supplements: ICEA S-108-720 (Extruded Power Cables 46-345 kV)

12

CEC Guides

CG1-96 Maximum Temperatures for Paper-Insulated Cables, use with: CS1 through CS4

CG3-05 Installation of Pipe-Type CableSystems, use with: CS2

CG4-97 Installation of Extruded DielectricCables 69-138 kV, use with: CS9

CG5-05 Extruded Power Cable Pulling, use with: CS8, CS9, ICEA S-81-570, S-95-658, S-94-649,

S96-659, S108-720, T-33-655


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13

CEC Guides (Cont)

CG6-05 Maximum Temperatures ofExtruded Dielectric Cables, use with:

CS8, CS9, S-94-649, S-97-682, S-108-720,

S-93-639

CG7-05 Replacement and Life Extension

of Extruded Dielectric 5-35 kV Cables, use

with:

CS8, S-94-649, S-97-682

14

CEC Guides (Cont)

CG8-03 Electric Utility Quality Assurance

Program for Extruded Dielectric Cables, use

with:

CS8, CS9, S-94-649, S-97-682, S-93-639, S-108-720

CG9-00 Installing, Operating, and Maintaining

Lead Covered Cables 5-46 kV, use with:

CS1, CS2, CS3, CS4, and CS8

CG10-02 Developing Specs for Extruded Cables

5-46 kV, use with: CS8

15

CEC Guides (Cont)

CG11-02 Reduced Diameter Extruded

Dielectric Cables 5-46 kV, use with:

CS8, S-94-649, S-97-682, S-XX-684 (future)

CG12-05 Minimizing the Cost of Extruded

Dielectric Cables 5-46 kV

CS8, S-97-682, S-94-649, S-93-639


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16

CS1-90 PILC Cable

Specification forImpregnated Paper-Insulated Metallic-Sheathed Cable,Solid-Type11th Edition, October

1990

Revision in progress

17

CS1-90 Scope

This specification applies to impregnated

paper-insulated, metallic-sheathed cable

of the "solid" type which is to be used for

the transmission and distribution of

electrical energy on electric utility systems.

Cables Rated 1 kV to 69 kV

18

CS1-90 Scope

The term solid-type cable designates a

hermetically sealed type of mass-

impregnated cable having an essentiallysolid cross-section impregnated with a

saturant of suitable viscosity, and

designed for operation without a pressure

medium.


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19

CS2-97 High Pressure Pipe-Type

Cable

Specification forImpregnated Paperand Laminated PaperPolypropylene Cable,High Pressure Pipe-Type 6th Edition, March

1997


20

CS3-90 Low Pressure Gas Filled

Cable

Specification for

Impregnated Paper

Insulated Metallic

Sheathed Cable, Low

Pressure Gas Filled-Type

3th Edition, October 1990


21

CS4-93 Self Contained Liquid

Filled Cable

Specification forLow and Medium

pressure SCLFcable8th Edition,

January 1993

Revision inprogress


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22

CS8-07 Extruded Cable 5-46 kV

Specification for Extruded Dielectric,Shielded Power Cables Rated 5 Through

46 kV

3rd Edition, February 2007

34 pages

23

CS8-07 Scope

Supplements ANSI/ICEA S-94-649 and

S-97-682

This specification covers cables rated 5-

46 kV, which are used for the distribution

of electric energy on electric utility

systems.

24

CS8-07 Additional Items

Qualification Tests

Appendixes

Industry Specifications, Standards, and

References

History of Cable Diameters

Procedure for Determining Diameters of

Cables

ANSI/ICEA Tables


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25

CS8-07 Additional Items

Partially replaced CS5 and CS6 (covers bothEPR and XLPE/TRXLPE cables): CS5 covered XLPE insulated cables from 5-46 kV

Originally published: 1969

CS6 covered EPR insulated cables from 5-69 kV Originally published: 1972

ANSI/ICEA standards have provided a way togreatly simplify the AEIC specifications.

The 2007 version largely adopted ICEA cablediameters; which use lower minimum pointthicknesses... Example next page->

26

Insulation Thickness Comparisons

175-mil average (previous AEIC)

158 190

176

176

min max

27

Insulation Thickness Comparisons

min-max (ANSI/ICEA)

165 205

min max


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28

Example

Install two joints and a short piece of newcable into section of failed old cable

Both cables 1000 kcmil 260 mil 25 kV

Old cable manufactured in 1979 to AEIC

CS5-79 Specification

New cable manufactured to ANSI/ICEA

Standard

29

CS8-00 Ranges of 1000 kcmil 25

kV Cable and Three Joints

1660 160

1665 120

1515 265

1645 95

1710 60

1500 1550 1600 1650 1700 1750 1800 1850

Diameter in mils

Z

Y

X

ANSI/ICEA

AEIC

30

CS8-07 Some Differences from 649

Includes “Guarantee” section

Includes Field Strippability Test

Shipment and Reels

Tree Count Test


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31

CS9-06 Extruded Cables and

Accessories rated 46-345 kV

Specification for Extruded InsulationPower Cables and their Accessories rated

above 46 kV Through 345 kV AC

1st Edition, December 2006

64 pages

32

CS9-06 Background Info.

Partially replaced CS6 and CS7: CS6 Covered EPR insulated cables from 5-69 kV


CS7 covered XLPE insulated cables from 69-138 kV


The first AEIC specification covering a complete cablesystem including joints/terminations

Covers both EPR and XLPE/TRXLPE cable systems

A system specification, not just a cable standard

Some differences from S-108-720 in conductor shieldmaterial and in the number and size of voids in the

insulation

33

CS9-06 Contents

General

Cables

Terminations

Joints Sheath Bonding/Grounding Systems, Link Boxes, and

SVL’s

Qualification Tests on System

Prequalification Tests on System

Electrical System Test After Installation

Quality Assurance

Shipping

Appendices (informative)


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34

CEC Guidelines

In the early days of the cable industry, noother guidelines were available within the

industry concerning cable operations,

installation, and maintenance.

CEC decided to begin developing some

guidelines for utilities to use.

35

Temperature Guides CG1 and CG6

CG1 – PILC Cables

CG6 – Extruded Dielectric Cables

Emergency Operations and Temperature

Limits

Principles and Basic Background Factors

Limiting Factors

Determination of Ampacity

36

CG1-07 PILC Temperatures

Guide for Establishing the MaximumOperating Temperatures of Impregnated-

Paper- and Laminated-Paper-Polypropylene-Insulated Cable4th Edition, June 2007

Scope: Operating temperature limits fortransmission and distribution paper andpaper-polypropylene insulated cable.


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37

CG6-05 Extruded Cable

Temperatures

Guide for Establishing the MaximumOperating Temperatures of Extruded

Dielectric Insulated Shielded Power

Cables

2nd Edition, November 2005

38

CG6-05 Scope

This guide primarily covers temperatures

limits for extruded dielectric cable in

underground installations.

Some guidance is provided for other

applications such as aerial installations

and riser pole applications.

39

CG5-05 Extruded Cable Pulling

Underground Extruded Power Cable

Pulling Guide

2nd Edition, June 2005


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40

CG5-05 Scope

Outlines the pulling parameters that needto be considered when installingunderground power cable in duct.

Based on EPRI Project EL-3333“Maximum Safe Pulling Lengths for SolidDielectric Insulated Cables”

Some sidewall pressure and tensionrecommendations differ from those ofcable manufacturers

41

CG5-05 Scope (Cont)

Pulling guides and computer software areavailable from many cable manufacturersand lubricant manufacturers.

Several of these guides provide a basicintroduction to cable pulling criteria.

Some of these manufacturers’ guides arelisted in the bibliography.

CG5 is intended to complement these

publications.

42

CG5-05 Scope (Cont)

The major points covered in the guideinclude:

Factors that influence pulling tensions such ascable type, conduit type and size, lubricants,and installation practices

Calculation of maximum pulling lengthsallowable without damaging the cable

Limits on cable tension and sidewall bearingpressure


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43

CG5-05 Contents

Cable Removal

Economic Considerations

Design Criteria and Pulling Limits

Pulling Tension Formulae

Sidewall Bearing Pressure Formulae

Sample Calculations

References

44

CG7-05 Extruded Cable

Replacement 5-35 kV

Guide for Replacement and Life Extension

of Extruded Dielectric 5-35 KV

Underground Distribution Cables

2nd Edition, November 2005

45

CG7-05 Scope

Covers extruded dielectric utility

distribution system cables rated 5-46 kV

Includes options for cable replacementand cable life extension based upon

current options within the industry today.


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46

CG7-05 Contents

Identifying Problem Cable Systems Decision Making Tools

Selection and Implementation of Solution

or Corrective Action

Reliability and System Enhancements to

Reduce Cable Failures

47

CG8-10 Quality Assurance

Extruded Cables 5-46 kV

Guide for Electric Utility Quality Assurance

Program for Extruded Dielectric Power

Cables

3rd Edition, August 2010

48

CG8-10 Scope

Techniques and procedures that an

electric utility may use to establish a

quality assurance program for extrudeddielectric power cable

Helps to ensure that the utility consistently

receives cable with the characteristics it

desires


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49

CG8-10 Contents

The Utility Cable Specification

Manufacturing Plant Audits Cable Inspection and Testing Keeping Records of Installation and

Operating Experiences Outline of a Cable Specification

Manufacturer Questionnaire

Inspection List

50

CG9-00 Installing and Operating

Lead Covered Cable 5-46 kV

Guide for Installing, Operating, and

Maintaining Lead Covered Cable Systems

Rated 5 kV Through 46 kV

1st Edition, May 2000

Reaffirmed in 2008

51

CG9-00 Scope

Lead-covered cables have been in use for

over 80 years and have demonstrated

exceptional service reliability. Two of the most common constructions in

use are paper-insulated lead-covered cable

(PILC) and lead-covered extruded-dielectric

cable.


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52

CG9-00 Scope (Cont)

Dealing with the lead on these types ofcables has become costly due to Federal

and State safety regulations.

Consequently, the use of lead covered

cables has declined and the expertise

needed to install and maintain them has

declined as well.

53

CG9-00 Scope (Cont)

This guide is intended to outline generally

accepted installation, operation, and

maintenance practices for lead covered

cables.

54

CG9-00 Contents

Manholes

Cable Handling

Cable Installation in Duct and Direct Buried Cable Accessories (Joints and Terminations)

Grounding

Identification and Installation Records

Inspection and Maintenance


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55

CG10-10 Developing Specs for

Extruded Power Cables 5-46 kV

Guide for Developing Specifications forExtruded Power Cables Rated 5 through

46 kV

2nd Edition, December 2010

56

CG10-10 Scope

This guide describes the various choicesthat an engineer must consider whendeveloping a medium voltage (5-46 kV)cable specification for utility use.

It is designed to acquaint the user withthose criteria necessary to ensure thecable will perform as intended.

57

CG10-02 Contents

The contents of CG10 basically follows the

outline of CS8 (MV Cable Spec) and CS9

(HV Cable Spec)


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58

CG11-02 Reduced Diameter

Extruded Dielectric Cables 5-46 kV

Guide for Reduced Diameter ExtrudedDielectric Shielded Power Cables Rated 5

Through 46 kV

1st Edition, January 2002

59

CG11-02 Scope

Replacing smaller PILC cables in existing,

space-limited infrastructure.

Provides general information to be used

when specifying and using cables with

reduced diameters.

60

CG11-02 Contents

Design Variables

Jacket

Metallic Shield

(Flat Strap or

Longitudinally

Corrugated Tape)

Insulation

Shield

Insulation

Conductor Shield

Center Conductor


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61

CG11-02 Contents (Cont)

Operating ConditionsMaximum Conductor Temperatures

Emergency Operating Temperatures

Metallic Shield Short Circuit Rating

Ampacity Requirements

62


Field Considerations

Duct Clearances

Duct Configurations

Terminations and Joints

Pulling Methods

Cable Handling

Proof Testing

63

CG12-05 Minimizing the Cost of

Extruded Cables 5-46 kV

Guide for Minimizing the Cost of Extruded

Dielectric Shielded Power Cables Rated 5

through 46 kV1st Edition, June 2005


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CG12-05 Scope

This guide provides general informationthat can be used to minimize the initial

purchase cost of extruded dielectric cable

rated 5-46 kV.

The variables allow the user to be aware of

some options to consider when attempting

to reduce the initial purchase cost of their

cable.

65

CG12-05 Contents

Design Variables

Jacket

Metallic Shield

(Concentric Neutral orTape Shield)

Insulation

Shield

(Semicon)

Insulation

Conductor Shield

Center Conductor

(Strand-filled)

66


Labeling

Packaging

Production Tests Quality Assurance Documentation

Qualification Tests

Industry Specifications, Standards,Guides, and Contact Information


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67

Conclusions

Standards and Specifications affect every aspect of

how we design our cable systems.

Many Standards and Specifications are

interrelated.

Individual Company specifications should

coordinate with these industry standards for an

optimal cable system design.

Industry Guides may be used to gain greater insight

into the application of the cable system

68

Standards, Specs, and Codes

A technical standard is an established

norm or requirement. It is usually a formal

document that establishes uniform

engineering or technical criteria, methods,

processes, and practices.

A specification is an explicit set of

requirements to be satisfied by a material,

product, or serviceWikipedia.org

69

Standards, Specs, and Codes (Cont)

Codes are rules established or adopted by

a governmental agency, required to be

followed. Codes represent the minimumacceptable requirements.

Governmental agencies usually obtain

adherence to codes by requiring permits.


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70

Standards and Specifications

Affecting Cable Systems

American National Standards Institute(ANSI)

ASTM International (ASTM)

Institute of Electrical and ElectronicsEngineers (IEEE)

71

Standards and Specifications

Affecting Cables

International Electrotechnical Commission(IEC)

Insulated Cable Engineers Association(ICEA)

Association of Edison IlluminatingCompanies (AEIC)

72

Codes Affecting Cables and

Systems

National Electrical Code (NEC)

National Electrical Safety Code (NESC)


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73

Codes Affecting Cables and

Systems

Code of Federal RegulationsOperating requirements

74

American National Standards

Institute (ANSI)

Established in 1918 by 5 engineering

societies and 3 government organizations

Composed of volunteer member

companies

75

ANSI Scope

ANSI oversees the development of

voluntary consensus standards for

products, services, and processes in theUnited States.

ANSI also coordinates U.S. standards with

international standards so that American

products can be used worldwide.


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76

ANSI Scope (Cont)

Accreditation by ANSI signifies that theprocedures used by the standards body in

connection with the development of

American National Standards meet the

Institute’s essential requirements for

openness, balance, consensus, and due

process.

77

ANSI Standards for Cable

ANSI/IEEE 386 – IEEE Standard for

Separable Insulated Connector Systems for

Power Distribution Systems above 600 V

ANSI C119.4 – Standard for Electric

Connectors

Connectors Used Between Conductors

Aluminum-to-Aluminum or

Aluminum-to-Copper

78

ASTM International (ASTM)

Originally known as American Society for

Testing and Materials

Uses a Consensus ProcessFrom http://en.wikipedia.org/

Consensus Process – “A group decision

making process that not only seeks the

agreement of most participants, but also the

resolution or mitigation of minority objections.”


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79

ASTM Publication Types

Standard Specification, that defines therequirements to be satisfied by the subject

of the standard.

Standard Test Method, that defines the

way a test is performed. The result of the

test may be used to assess compliance

with a Specification.

80

ASTM Publication Types (Cont)

Standard Practice, that defines a

sequence of operations that, unlike a test,

does not produce a result.

Standard Guide, that provides an

organized collection of information or

series of options that does not recommend

a specific course of action.

81

ASTM Standards for Cable

ASTM B 230 – Standard Specification for

Aluminum 1350-H19 Wire for Electrical

Purposes ASTM B 8 – Standard Specification for

Concentric-Lay-Stranded Copper

Conductors, Hard, Medium-Hard, or Soft

Others for plastic and other materials


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82

Institute of Electrical and Electronic

Engineers (IEEE)

The IEEE is an international non-profit,professional organization for the

advancement of technology related to

electricity.

It has the most members of any technical

professional organization in the world, with

more than 365,000 members in around

150 countries.

83

IEEE Background

IEEE was formed in 1963

Power and Energy Society (PES)

(Formerly Power Engineering Society)

Main group of the IEEE PES that develops

standards for cables and accessories is

the Insulated Conductors Committee (ICC)

84

IEEE Standards and Guides (ICC)

Develops and Maintains Standards andGuides for Cables Systems and

Accessories: IEEE Std 386 – Separable Connectors

IEEE Std 404 – Cable Joints

IEEE Std 48 – Cable Terminations

IEEE Std 400 (and associated pointdocuments) – Diagnostic Testing in the Field

Many others


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85

National Electrical Code (NEC)

NEC 2008, NFPA 70 90.2 Scope (B) Not Covered – (5)

“Installations under the exclusive control of

an electric utility where such installations…

b. Are located in legally established easements

or rights-of-way designated by or recognized by

public service commissions, utility

commissions, or other regulatory agencies

having jurisdiction for such installations....”

86

NEC (Cont)

The NEC does not have jurisdiction over

utilities.

However, the NESC does have jurisdiction

over utilities.

87

National Electrical Safety Code (NESC)

Work began on the

NESC in 1913 at the

National Bureau of

Standards (NBS) As NBS Handbooks

The 4th edition (1927)

is shown here.

ANSI gets approval

by sending out to

interested

committees.


42/1093

88

NESC (Cont)

IEEE C2 (IEEE is the

secretariat)

Recognized by ANSI

Adopted as law by

most states within the

US as the binding

code for electrical

power systems.

89

NESC (Cont)

“…Applicable to the systems operated byutilities, or similar systems and equipment ofan industrial establishment or complexunder the control of qualified persons.”NESC Abstract, 2007 Edition

Part 3 – Safety Rules for the Installation andMaintenance of Underground ElectricSupply and Communication LinesSection 33 Supply Cable

Section 35 Direct-buried Cable

90

International Electrotechnical

Commission (IEC)

The IEC is a not-for-profit, non-

governmental international standards

organization that prepares and publishesinternational standards for all electrical,

electronic, and related technologies

Instrumental in developing the International

System of Units (SI) (metric system)


43/1093

91

IEC (Cont)

ANSI is represented on the IEC throughthe US National Committee

IEC Technical Committee 20 is

responsible for Electric Cables

92

IEC Cable Standards

IEC 60502 – Power cables with extruded

insulation and their accessories for rated

voltages from 1 kV up to 30 kV



voltages above 30 kV up to 150 kV - Test

methods and requirements

93

IEC Cable Standards (Cont)



voltages above 150 kV up to 500 kV IEC 60287 – Calculation of the continuous

current rating of cables

IEC 60228 – Conductors of insulated

cables


44/1093

94

Insulated Cable Engineers

Association (ICEA)

The ICEA is an organization that developsstandards for electric power, control,

telecommunications, and portable cables

Established in 1925

Not-For-Profit association

Members are sponsored by about thirty

North American cable manufacturers

Works with cables only – not accessories.

95

ICEA Document Types

Publications or Guides

ICEA P-32-382-2007 Short-Circuit

Characteristics of Insulated Cable

Test Methods

ANSI/ICEA T-31-610-2007 Test Method for

Conducting a Longitudinal Water Penetration

Resistance Test on Blocked Conductors

Standards

ANSI/ICEA S-94-649-2004 Concentric NeutralCables Rated 5 Through 46 kV

96

ICEA MV Cable Standards for

Utilities

ANSI/ICEA S-94-649-2004 Concentric

Neutral Cables Rated 5 Through 46 kV

ANSI/ICEA S-97-682-2007 Utility ShieldedPower Cables Rated 5 Through 46 kV

ANSI/ICEA S-108-720-2004 Extruded

Insulation Power Cables Rated Above 46

Through 345 kV


45/109

Medium Voltage Cable

OverviewManufacturing, Testing, Cable

Prep and Installation

Doble Tutorial, Boston

March 31, 2011

Background

Joe Zimnoch Jr• Sr Applications Engineer- Okonite

• 27 years

– 8 Years in HV Lab

– Remainder in Application Engineering

Cable Design - Components

• Conductor

• Semiconducting Strand Screen

• Insulation

• Semiconducting Insulation Screen

• Metallic Shield

• Protective Covering

– Jacket / Armor

Conductors -Purpose

• To provide a low resistance path for the flow ofcurrent such that the

(1) cable’s temperature ratings are notexceeded

(2) voltage regulation (drop) is withinacceptable limits

In other words, why do we

have different conductor sizes?

Conductors

• Conductivity

100% Copper

61% Aluminum

16.6% Steel

15% Tin

8% Lead

108% Silver

• Shapes – Class B

Concentric – Compressed - Compact

• Other Classes C,D,H, …..

Conductor Terminology

What are MCM and kcmil ?

• Answer: Thousands of circular mils

• M and k: M = Roman Numeral; MKS abbreviation for thousand

• 1 mil = 0.001” (¼” = 0.25” = 250 mils; 1” = 1000 mils)

• CM and cmil = circular mil (area of a circle w/o )• If Area (sq in.) = r 2

• Then 1 circular mil = D2 (diameter of wire in mils squared)

• Example

Thus for a solid #10 awg wire

– Diameter = 0.1019” or 101.9 mils

– CM area = (101.9)2 = 10,380 circular mils

AWG- American Wire Gauge


46/109

CMA Calculation for 500 MCM Conductor

For a 500 mcm (class B – 37 x 0.1162”)

Diameter of = 0.1162” or 116.2 mils

area of 1X = (116.2 mils)2 = 13,502 circular mils

(13,502 circular mils) x (37) = ~500,000 circular mils

500,000 circular mils = 500 mcm (or kcmil)

For a 500 mcm (class I – 1225 x 0.0201”)

Diameter of = 0.0201” or 20.1 mils

area of 1X = (20.1 mils)2 = 404 circular mils

(404 circular mils) x (1225) = ~500,000 circular mils

500,000 circular mils = 500 mcm (or kcmil)

Conductors - Classes

500 mcmClass B – 37 wires (116.2 mils/wire)

Class C – 61 wires (90.5 mils/wire)

Class H – 427 wires (34.2 mils/wire)

Class I – 1225 wires (20.1 mils/wire)

EHB Excerpt, P. 1, Table 1.1

Conductor Size

Circular Mil Area

(circular mils)

#1 83,690

1/0 105,600

4/0 211,600

250 mcm 250,000

500 mcm 500,000

Conductors – Class B

1

1 + 6 = 7

1 + 6 + 12 = 19

1x, 7x, 19x, 37x, 61x, 91x, 127x, etc…

7 wires

#24-#2

19 wires

#1 – 4/0

37 wires

250-500 mcm

61 wires

750-1000 mcm

Conductors: Stranding – Class BClass B Conductor Stranding Types

500 mcm (37 strand) Diameters Differences

0.813” 0.788” 0.736”

(-3%) (-10%)

All three have the SAME cross sectional area

i.e. all are 500 kcmil.


47/109

ass on uctor tran ng

Types

Cross sectional area of each conductor

500 kcmil 500 kcmil 500 kcmil

All three have the SAME cross sectional area i.e. all are 500 kcmil.

The main difference is that the concentric has a large amount of

space between the individual strands that is not accounted for in the

cross section area calculation. Conversely the compact round

conductor has very little trapped area between the strand

Trapped air NO Trapped

air

Compressed, Compact & Flex

Flex Compressed Compact

Round, C/R

Rope Strand

• 350 kcmil

• 37 Ropes

• 24 wires/rope

• 37x34=888 wires total

• 1 wire OD=20 mils

• 202= 400 cm/wire

• 400 x 888=355 kcmil

Compact vs. Compressed

in a Connector

• When compressed into the same size

connector, both the compact conductor

AND compressed look almost identical

since they both have the same cross

sectional area (the area is based on the area

of EACH individual strand times the

number of strands.

• The cross sectional area is NOT based onthe overall diameter of the conductor.

500 mcm connector:

•1 compressed conductor in one side

•1 compact round conductor in the other side.

They were then crimped using 500 mcm

die and then cut across the crimps


48/109

Conductor A - crimped in 500

mcm connector

Conductor B - crimped in 500

mcm connector

Which is compact? A or B? Which is compact? A or B?

A=Compact Conductor B=Compressed Conductor

A=Compact Conductor

(notice SQUARED strands

on left side of picture)

B=Compressed Conductor

(notice ROUNDED strands

on left side of picture)

400 mcm vs. 500 Connector

500

mcm

400

mcm Diff

Length 3.53” 3.00” -0.53”

OD 1.06” 0.965 -0.095”

ID 0.841” 0.767” -0.074”

Wall 0.110” 0.100” -0.010

500 mcm c/r OD = 0.736”


49/109

Why?

• Connectors are designed based on compressionratio.

• The compression ratio is the area of theconductor (not counting the air gaps betweenthe strands) and the area of the connector before and after the crimp.

• The area of the conductor (again not countingthe air gaps between the strands) is the samefor both the compressed and compactconductor.

Connectors for

Pre-Molded Accessories

( Elbows, Tee-Bodies, Splices, etc)

• Shorter crimp length

• Heavy wall of rubber

–Use connector/lug per

manufacturers recommendation.

Wire Drawing - Mechanical forming

by tension through a die.

5/16"ROD SLIGHTLY SMALLER WIRE

TUNGSTAN CARBIDE DIE

PULL DIRECTION

American Wire Gauge (AWG)

• In order to make a # 10 awg wire from

a 5/16” Cu or Al rod, the rod must be

drawn through - 10 die.

• Likewise, a #24 awg must go through -

24 die.

American Wire Gauge (AWG)

• Industry standard for electrical wire.

• Based on 40 sizes between #36 and 4/0.

• OD of a 4/0 = 0.46” (~ 0.50”)• OD of a #36 = 0.0050”

• Using geometric progression, the ratio ODdiameters is:

Therefore an increase in AWG size increases OD by 12.3%

OR


50/109

The End Result

• A #10 awg has:

– OD = 0.10” – Area = 10, 380 circular mils

– DC Resistance = 1 ohm/mft (copper)

– Weight = 10 π (or 31.4 lbs/mft)

• Increasing or decreasing 10 awg sizes changes thearea, resistance and weight by a factor of 10.

–#10 to #20

–10, 380 to 1,020 cm

–0.999 to 10.1 ohms/mft

–31.4 to 3.1 lbs/mft

The Not’s

You can determine the OD of 40 different sizes from

a #36 up to a 4/0. Using:

To determine the the OD of a #24, substitute 24 for n;

likewise for a #1, n = 1.

In order to determine the next larger size above #1

(remember there are 40 sizes) n = 0 (Or 1 zero aka

1/0).

Now for a 2/0 substitute n = -1, for 3/0 n = -2 and for

4/0 n = -3.

Calling the sizes -1,-2 and -3 does not play well, so

they are are called 1/0, 2/0, etc..

Not

• Not - Function: adverb Etymology: Middle

English, alteration of nought, from nought,

• 1 —used as a function word to make negative

a group of words or a word

• 2 —used as a function word to stand for the

negative of a preceding group of words

An increase of 1 AWG size

→ 12.3% OD increase

→ 26.1% Area increase

↑ # 2 to #1 (solid)

→ 257.6 mils * 1.123 = 289.3

→ 66,360 cm * 1.261 = 83,680

AWG Trivia

An increase of 2 AWG sizes

→ 26.1% OD increase

→ 59 % Area increase

↑ #14 to #12 (solid)

→ 64.1 mils * 1.261 = 80.8

→ 4110 cm * 1.59 = 6,535

An increase in 2 AWG sized yields ~60% weight increase.

For example a #12 weighs 20.1 lbs/mft versus 12.66 for a #14.

Romex, 250 ft - 14/2 w/g $55Romex, 250 ft - 12/2 w/g $84

5000 lbs coils (bales) of 5/16” copper rod in Paterson. 5000 lbs bales of 5/16” copper rod in Santa Maria, CA


51/109

5000 lbs coils (bales) of 1/4” aluminum rod in Santa Maris, C 5/16” copper rod being paid off.

Copper rod thru die. Larger OD on Left; smaller on Right.

Multiple die w/Copper rod. Multiple die w/Copper rod in action.

Oil and water mixture for cooling and lubrication


52/109

Empty shop reel (bobbin) be ing loaded w/drawn wire. Bobbins loaded w/drawn wire . Approx 600 lbs of wire per bobbin .

A #14 wires exits the drawing process at approx 4000 ft/minute.

One wire fed into front of strander

•6 wires spun around 1•12 wires spun around 7

•etc..

Bobbin

loaded

onto head.

One wire fed into front of strander.


53/109

Wires being spun around center wire(s). Close up of 6 wires being spun around center wire at closing die.

Close up of 18 wires being spun around center 19 wires.

Finished conductor now ready to be insulated.

Corona or Partial Discharge

In Air

A partial arc ordischarge to moisture,dust, or grounded areas.

In a Cable

Discharge that can occuroff the conductor (sharp points), between layers,at a void or contaminateand at the shield.


54/109

Corona Likes Sharp Points

Corona discharge off sharp points at 500 kV-AC. Used to

draw voltage upwards away from grounded base of pothead.

800 kV AC

Transformer

Connected

to 230 kV

Pipe Cable

in 500 kV

Lab

Potheads.

Conductor, Conductor Screen, Insulation,

Insulation Screen, Shield/Neutral, Jacket

Insulation and Screens

Insulation Screen

EPR or XLPE

Insulation

Conductor Scree

Discharge-Free vs. Discharge Resistant

Discharge-Free Discharge Resistant

Okonite Company X

Company A

Company B

Company C

Company D

Company J

Company F

Company G

Company H

Company M

Company J

Vulcanizing

Curing

Cross-linking (XL)

All are equal terms:

to convert a rubber or plastic compound into a

“Thermoset” state

Equal Terms


55/109

Over Cooked Spaghetti Analogy

Thermoplastic

• Can be melted back to liquid

• Fair deformation resistance (memory)

• Limited temperature rating (75C)

Thermoset

• Cannot be melted back to liquid

• Excellent deformation resistance (memory)

• Higher temperature rating (90C to 105C)

Thermoplastic

Melts back to its

original liquid form

Thermoset burns

but never reverts

back to its

original liquid form

Insulation – Typical Materials

Thermoset

• Ethylene Propylene Rubber (EPR)

• Crosslinked Polyethylene (XLPE)

• Tree Retardant Crosslinked Polyethylene (TR-XLPE)

Thermoplastic

• Polyethylene (PE)

• Polyvinyl Chloride (PVC)

• PVC/Nylon

Insulation – Thicknesses

Voltage

Rating 100 % 133%

5 kV

(shielded)

90 mils 115 mils

15 kV 175 mils 220 mils



0.001”= 1 mil, alternately

1 inch = 1000 mils

Insulation – Thicknesses

100 % 133 % 173%

Relay Clears

< 1min.

Relay Clears

< 1hour

Indefinite

For 3 phase

systems

For 3 phase

systems

For delta systems

where one phase

may be indefinitely

grounded.


56/109

133% and 173% Insul Level

Protects Un-faulted Cables

when One Fails

• When one cable fails, the voltage on the twoun-faulted cables may increase from 133 to

173% of the phase-to-ground voltage.

• Depends if Wye or Delta and how balanced

the loads are.

Fault

Extrusion

• Deformation process.

• Shaping by pushing material through a die.

RAM

DIE

CYLINDER

LIQUID METAL, RUBBER, ETC..

EXTRUDED ROD, BAR, ANGLE, ETC..

Four Types of CV TubesFour Types of CV Tubes


57/109

ORANGEBURG

MANUFACTURING

• CV Extrusion equipment located in peak of roof

• CV curing tube runs length of building

CV Curing Tube CV Equipment

• CV Extrusion equipment located in peak of roof

Continuous Vulcanization (CV) ExtrusionContinuous Vulcanization (CV) Extrusion

• CV curing tube runs length of building

CV Curing Tube

Curved

CV Curing Tube

Support Beam

Straight


58/109

CV Curing Tube

Curved to Accommodate

Catenary Shape of Cable

• Finished Cable Core:

• Conductor

• Conductor Screen

• Insulation• Insulation Screen

Why is a Shield Needed?

• Controls stresses within the insulation

–Permits thinner insulation

• Confines field within shield

– No potential on surface of cable

• Controls discharge to ground

• Above 2000 volts is when the above

becomes apparent.

Greater than 2000 VOLTS


59/109

5 kV NS at 4160 volts

The 2005 NEC reduced rating from 5 to 2.4 kV for NS

Also completely eliminated 8 kV NS cables

Discharge from phase-to-phase

5 kV NS at 4160 volts

Discharge

from

phase-to-

phase

and

phase-to-

ground

Shielding

• Confines the electrical field within the insulation.

• Reduces the chance of electrical shock

• Provides a symmetrical distribution of stress

• Prevents surface discharge

• Reduces electrical interference

• Monitor voltage

• Provides a path for fault currents

• Can be used as a neutral

• Can affect ampacity rating (circulating current)

Factors to Consider for Shield Design

• Fault current capability

• Use as neutral (single phase or 3 phase)

• Shield voltage (single point grounding)

• Shield circulating current (multi-point grdg)

and its effect on ampacity

• Flexibility and minimum bending radius

• Ease of making ground connections

Effect of Fault Current in

Shield on Jacket

• Fault current returning to ground on theshield will produce higher than normal heat.

• Excessive heat can melt the overlying jacket.

• A lower the resistance shield, produces lessheat.

• Adding more copper (wires, tape, armor)lowers the shield resistance.


60/109

Copper Tape Shield Wire Shield or Concentric Neutral

Copper Tape and WiresLongitudinally Copper Shield (LCS)

Flat Copper Straps

(PILC Replacement Cable)Lead Sheath


61/109

Single Conductor w/Armor

Shield Fault Current Capability

Shield Design Circular Mil Area

(CM)

Fault Capability

-10 cycles (kA)

5 Cu Tape, 12.5% lap 18,974 3.22

5 Cu Tape, 25% lap 20,494 3.48

5 Cu Tape, 50% lap 25,100 4.26

5 Cu LCS, ¼” overlap 31,000 5.26

6 x 20 x 175 Cu Straps 26,738 4.54

16 x 35 x 200 CS (90% Coverage) 32,870 5.58

11 x #14 wires (1/3rd N for 2/0 Cu) 45,197 7.67

18 x #14 wires (1/3rd N for 350 Al) 73,959 12.55

5 Cu Tape, 12.5% lap/Al Armor 103,423 17.55

0.095” Lead Sheath 511,100 86.74

1.25” core OD, thermoplastic jacket (constant=0.288)

Per Okonite EHB, Page 15

Shielding – Types, Listed from

High Resistance to Low

• Flat copper tape (High Resistance)

• Longitudinally corrugated tape(LCS) copper or bronze tape

• Concentric Cu wires & Flat Straps

• 1/C Al. Armor-CLX

• Lead sheath (Low Resistance)

Shielding Resistance dictates amt of circulating current

GRAPHIC OF SINGLE POINT GROUND

a.k.a – open circuited shield

CONDUCTOR SHIELD

DISTANCE

SHIELDVOLTS

25 to 100 V

CURRENT FLOW

MAGNETIC FIELD

Leakage I thru Insul is shunted to grd via shield. Current

thru shield resistance produces voltage.

GRAPHIC OF MULTI-POINT

GROUND

CONDUCTOR SHIELD

DISTANCE

SHIELDVOLTS

0 V

a.k.a – short circuited shield

TRANSFORMER EFFECT OF

MULTI-POINT GROUND

CONDUCTOR SHIELD

SHIELDCONDUCTOR

a.k.a – short circuited shield


62/109

Shield Circulating Current

• When multi-point grounded acts like atransformer.

• The lower the shield R, the closer we approach

1:1.

• If the shield R is ½ of the conductor

resistance, theoretically as much as 50% of the

load current may circulate on the shield.

Concentric Neutral (Shield)

• Acts as both a neutral and a shield.

• Concentric wires return phase current

– Full neutral for single phase (2/C

Cable)

– 1/3rd neutral for three phase

Concentric Neutral (Shield)

• Acts as both a neutral and a shield.

• Concentric wires return phase current

– Full neutral for single phase (2/C Cable)

– 1/3rd neutral for three phase (return current

120° out of phase).

1/0 AWG AL1/0 AWG AL

16 x #14 WIRES -EQUAL TO 1/0 AL

11 x #14 WIRES

- EQUAL TO 1/3RD

OF A 4/0 AL

SINGLE PHASE 1/0 ALUM

ANY VOLTAGE

THREE PHASE4/0 ALUM

ANY VOLTAGE

4/0

Scenario D (grounded at ONE point)1-1/C 500 kcmil Cu, 220 Okoguard, 1/3 rd Neutral Cables per 3”

duct, 3 ducts 7.5” on center

Ampacity = 583 amps

Losses = 29.16 watts/ft total

Scenario E (grounded multiple points)1-1/C 500 kcmil Cu, 220 Okoguard, 1/3 rd Neutral

Cables per 3” duct, 3 ducts 7.5” OC,

Ampacity = 424 amps


Ampacity Comparison

Single Point

vs.

Multi-pointGrounding

Scenario A (3-1/C’s per Duct)3-1/C 500 kcmil Cu, 220 Okoguard, 1/3 rd Neutral Cables

Ampacity = 449 amps


Scenario E (1/C per Duct)1-1/C 500 kcmil Cu, 220 Okoguard, 1/3 rd Neutral Cables

per 3” duct, 3 ducts 7.5 ” OC

Ampacity = 424 amps


Ampacity Comparison

1/C per Duct

vs.

3-1/C’s per Duct(Both Multi-point grounded)

15 kV, Aluminum Condr, URD, Direct Buried, 1 Ckt,

Conductor

Size

Triangular Config Flat Spcd Config

75% LF 100% LF 75% LF 100% LF

1/0 (1/3) 207 187 231 206

4/0 (1/3) 308 276 340 301

350 (1/3) 405 362 430 376

500 (1/3) 488 432 499 431

750 (1/3) 593 521 578 494

1000 (1/6) 698 609 666 570

Soil=90 RHO, 90C Condr, 25C Soil

Comparison Triangular & Flat Spaced Configuration

Use Flat Spacing for Small Conductor Installations

S o u r c e : N R

E C A


63/109

Shield/Neutral Summary

• Controls voltage stress in the insulation.

• Some shields can also be used as a neutral.• Multi-point grounding recommended to

reduce shield voltage and for safety.

• Shield must also be designed to carry the

available phase-to-ground fault current

• The more copper in the shield, the greater

the circulating current depending on the

physical arrangement and load current.

Jackets

• Cable Jacket – Nonmetallic Outer Coveringof a Cable

• Two Broad Categories: Thermoset and

Thermoplastic

• For each application, the operating

temperature and environment must be

considered

Jacket – Desired Characteristics

• PHYSICAL

• CHEMICAL

• TEMPERATURE

• MOISTURE

• AGING

• FLAME

• SMOKE

Types of Cable JacketsThermoplastic

– PE (Polyethylene HD, MD, LD, LLD)

– PP (Polypropylene aka living hinge)

– PVC (Polyvinyl Chloride)

– TP-CPE (Thermoplastic-Chlorinated Polyethylene)

– TPPO (Thermoplastic Polyolefin - low smoke zero halogen-

transit industry)

Thermoset

– Neoprene (PCP - Polychhloroprene)

– Hypalon (CSPE – Chlorosulfonated Polyethylene)

(discontinued)

– TS-CPE (Thermoset-Chlorinated Polyethylene)

– XLPO (Cross Linked Polyolefin - low smoke zero halogen-

transit industry)

Factory Tests Factory Electrical Tests

• DC Conductor Resistance

• Insulation Resistance (Megger)

• Shield Continuity

• Corona (4 times operating;


64/109

AC Withstand – 5 MinutesNominal Voltage

Rating

Nominal

Wall

Thickness

(mils)

200 v/mil

AC Test

Voltage

(kV)

5 kV-100% 90 18

5 kV-133% 115 23

5/8 kV-133/100% 140 28

15 kV-133% 175 35

15 kV-133% 220 44

25 kV-100% 260 52

28 kV-100% 280 56

25 kV-133% 320 64

28/35 kV-133/100% 345 69

35 kV-133% 420 84

200 v/mil x 220 mils = 44,000 v or 44 kV

AEIC PARTIAL DISCHARGE REQUIREMENTS

Maximum Permissible Discharge

______________________________________________________________________

Stress as a Percent of Rated Voltage to Ground

150% 200% 250% 300% 400%

1973 5 30 55 80 80

1975 5 20 35 50 -

1982 5 20 35 50 -

1983 Okonite established internal “flat line” requirement

1987 5 5 5 5 10

1996 5 5 5 5 5

Cable

Prep


65/109


66/109

80%

80%

High Voltage but Low Stress

High Stress Area/Near Ground

Knife Cuts = Termination Failures

Wide SC Strips = Higher Stripping Tension

Outer Semicon Thickness-URD

Concentric Neutral Wires

Insul OD

(inches)

Min/Max

(mils)

Cable Sizes

(conductor/insul thickness)

0-1.000 30/60 #2 to 3/0,220

#1 to 2/0, 260

1.001-1.5 40/75 4/0 to 750, 220

3/0 to 500, 260

1/0 to 350, 345

1.501-2.0 55/99 1000, 220

750 to 1000, 260

500 to 1000, 345


67/109

Outer Semicon Thickness- Non-URDCu Tape, LCS, fine wires

Insul OD

(inches)

Min/Max

(mils)

Cable Sizes

(conductor/insul thickness)

0-1.000 24/60 #2 to 3/0,220

#1 to 2/0, 260

1.001-1.5 32/60 4/0 to 750, 220

3/0 to 500, 260

1/0 to 350, 345

1.501-2.0 40/75 1000, 220

750 to 1000, 260

500 to 1000, 345

Outer Semicon Thickness- Non-URD

Insul OD

(inches)

Min/

Max

(mils)

Cable Sizes

(conductor/insul

thickness)

0-1.000 24/60 #2 to 3/0,220

#1 to 2/0, 260

1.001-

1.5

32/60 4/0 to 750, 220

3/0 to 500, 260

1/0 to 350, 345

1.501-

2.0

40/75 1000, 220

750 to 1000, 260

500 to 1000, 345

ICEA

now allows

24 mils

ALL SIZES

Ripley Banana Peeler

(Semicon Scoring Tool)Olfa 300 Cutter

Speed Systems Spiral Semicon

Scoring Tool


68/109

AB

Pull Direction ?

A to B ?

B to A ?

Question?

Cradled Triplexed or Triangular•Cradled – When cables are pulled in parallel.

•Triplexed – When cables are twisted together at factory.

•Triangular – When cables pulled in parallel, but with a percent fill that is greater than 40%.

Triplexed (twisted) Cable on ReelParalleled (side-by-side) Cable on

One Reel


69/109

If the maximum pulling tension is

exceeded, the strands next to the

pulling eye can elongate and break.

It is possible to exceed the max

pulling tension and not damage the

Maximum Pulling Tension Calculation

Tmax = 0.008 x n x CMA {For 1/C or Triangular}

and

Tmax = 0.008 x (n-1)x CMA {For Cradled}

where,

0.008 is the maximum force per circular mil area that can be

exerted on the conductor without exceeding the tensile strength of

the conductor.

Examples

For 3-1/C 350 mcm - Triangular

Tmax = 0.008 x 3 x 350,000

Tmax = 8400 lbs

For 3-1/C 350 mcm - Cradled

Tmax = 0.008 x (3-1) x 350,000Tmax = 5600 lbs

Conductor Si ze No. of Conductors

AWG Cir. Mils n=1 n=2 n=3

2 66,360 530 1060 1595

1 83,690 670 1340 2010

1/0 105,600 845 1690 2535

2/0 133,100 1065 2130 3195

3/0 167,800 1342 2684 4026

4/0 211,600 1693 3386 5079

250 mcm 250,000 2000 4000 6000

350 mcm 350,000 2800 5600 8400

500 mcm 500,000 4000 8000 10000

750 mcm 750,000 6000 10,000 10000

1000 mcm 1,000,000 6000 10,000 10000

1250 mcm 1,250,000 6000 10,000 100001500 mcm 1,500,000 6000 10,000 10000

2000 mcm 2,000,000 6000 10,000 10000

Tension, Lbs

Maximum Pulling Tension Limits

Max Tension Limits

1 conductors = 6000 lbs

2 or more conductors = 10,000 lbs

EXAMPLES

OF

COMPRESSION TYPE

PULLING EYES AND BOLTS

Pulling eye.Pulling eye.

Pulling bolt.

Pipe Cable

Pull


70/109

3-1/C Pulling Bolts in Yoke3/C Common Pulling Eye

3/C Common

Pulling Eye

Maximum Pulling Tension

Limit Pulling Grips

to

1000 lbs per Grip

• Not just pulling on conductor

• Pulling on jacket, shield andinsulation also.

• Damage can occur to theseother layers.

• Where the damage starts orstops cannot be determined.

Condux

Re-useable Pulling Eye

Re-Usable Pulling Eye Graphic


71/109

Tapping in Wedge

Completed

3 and 4 Conductor Sling


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3 and 4 Conductor Sling

Attached to Common Head Dynamometer set-up on pull. Complicated:Most measure angles and distances then input into

formula.

Line

Tensiometer


73/109

Sidewall PressureSimplified

For Single Conductor:

SWP = Tout/rbendExpressed in Lbs/foot of radius

Smaller Radius = Higher “SWP”

Larger Radius = Lower “SWP”

Kirk

1000 LBS

SWP on Rope

1000 LBS/1 ft=

1000 lbs/ft of radius

George

SWP on Rope

1000 LBS/10 ft=

100 lbs/ft of radius

1000 LBS

•Damage from excessive sidewall

pressure.

•Shield can cut into insulation and

cause failure.

Shield Damage from

Over-bending

Copper Tape Shield


74/109

Simple Min Bend Radii Gauge

NEC fill limits were designed to prevent fire hazards. They did not

want an electrician installing 20 - #12 wires in a ½” conduit andcreating a fire.

Percent Fill Calc

• 3-1/C 500 mcm, 15 kV in 5” Duct

• Cable OD = 1.49”

• Duct ID = 5.047”• A = πR 2 -or- πD2

4

• Area Cable = (π(1.49”)2/4) x 3 = 5.23 sq inch

• Area Duct = π(5.047”)2 = 20 sq inch, EHB p39, T 7-1

• Fill = 5.23/20 x 100 = 26.15 %

Percent Fill Calc

• 3-1/C 500 mcm, 15 kV in 4” Duct

• Cable OD = 1.49”

• Duct ID = 4.026”• A = πR 2 -or- πD2

4

• Area Cable = (π(1.49”)2/4) x 3 = 5.23 sq inch

• Area Duct = π(4.026”)2 =12.72sq inch, EHB p39, T 7-1

• Fill = 5.23/12.72 x 100 = 41.16 %


75/109

Effects of Duct Size

3-1/C 500 mcm Cu, 90C in 4” PVC,

36” to Top of Duct

Insulation

Thkns

175 mils 508 amps

220 mils 509 amps

580 mils 510 amps

Cable Clearance (min ½”)

Utilities are not bound by NEC % Fill Limits. They

use cable clearance.

Jam Ratio in Round Duct

JR=2.8 JR=3.2In Round Duct it does not make sense:

• at 2.8 there is not enough room for them to jam

•at 3.2 there is enough room for the three of them

•So why ????

JR=3.2JR=2.8

JAM RATIO (ELONGATED DUCT)Conduit Manufacturers are permitted, per industry

standards, to make sweeps as much as 10% out of

round or Elongated.

In Elongated Sweeps:

• at 2.8 there is enough room for them to jam in the vertical direction

•at 3.2 there is enough room for them to jam in the horizontal direction

Jamming

• If the jam ratio falls between 2.8 and 3.2, it does

not mean the cables will automatically jam; it just

means there is a possibility of jamming.

• The tendency to jam increases with pull length and

the number of bends. Both of these increase

tension.

• Remember, each bend increases tension

significantly.

• It is always better to set up a pull with the majority

of the bends closest to the feed location (reel).


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Preventing Cable Jamming

• There are two ways of preventing cable

jamming:

•Change cable or conduit

size to avoid 2.8 – 3.2 Ratio

•Install Triplexed cable. Triplexed

Cable

Jam Ratio

and

% Fill

and

Weight

Correction

Factor, c

Coincidentally, percent

fill values between 29

and about 40% usually

land up in the 2.8 to 3.2

Jam Ratio range.

Typical Pull Orientations

•Straight Pull

•Bends (Sweeps)

•Incline

•Vertical

Straight Section

T = Tension at pulling eye (lbs)

L = Length of run (ft)

W = Weight of cable (lbs/ft)

C = Weight correction factor

f = Coefficient of friction

T = L x W x C x f

Coefficient of Friction (f)

The friction that exists between the

cable jacket and the duct surface

• f = 0.50 for dry cable

• f = 0.35 for well lubricated cable

f = Ff /Fn (Ff = force to move object/Fn = weight of object)


77/109

Weight Correction Factor (C)

• Adjusts the cables weight to account for thenumber of cables in contact with the duct

• Also adjusts for the force exerted by the

cable to the adjacent cables

Typical Values

Cradled = 1.44

Triangular = 1.22

Weight Correction Factor adjusts

the equation to account for number

of cables in contact with duct

C = 1 C = 1.44 C = 1.22

Weight Correction Factor Weight Correction Factor

2

d-D

d-1

1c

2

d-D

d4/31c

⎥⎦

⎤⎢⎣

⎡=

⎥⎦

⎤⎢⎣

⎡+=Cradled:

Triangular:

d=Cable ODD=Conduit ID Bends and Sweeps

Bends (Sweeps)

• Friction between cable and duct increases as

cable traverses bend

• Act as tension multipliers

• Tension increases exponentially due to

change in direction

• Analogy: Tension in household extension

cord increases as it is pulled around edge of

doorway

Tension Out of a Bend

Tout = Tension out of the bend (lbs)

Tin = Tension into bend (lbs)

e = Naperian Log Base (2.7180)

f = Coefficient of friction

a = angle of bend (radians)

Tout = Tinecfa


78/109

Values of ecfa

For Conduit Bends

cf 30° 45° 60° 90°0.30 1.17 1.27 1.37 1.60

0.35 1.20 1.33 1.45 1.74

0.40 1.23 1.37 1.52 1.88

0.50 1.30 1.48 1.69 2.20

0.60 1.37 1.60 1.88 2.57

0.85 1.48 1.80 2.20 3.25

Hi f

Hi C

90°Bend

200

Bend Multiplier Effect

.

1000 lbs IN

3250 lbs OUT

Tout = Tinecfa

Tout =1000 lbs x (3.25

)

Tout = 3250 lbs

AB

Pull Direction ?

A to B ?

B to A ?

Question?

Answer - A to B

Each bend, approximately,

doubles the amount of

tension, thus if the cable is

pulled trough the bendsearly in the pull, the

tension that is multiplied is

much smaller.


79/109

Multi-wheel Sheaves –

Larger Radii, can fit thru

MH openings

Quadrant block

Roller assemblies are

designed to fit

through the chimneyof the manhole.

Model No. Radius Sheaves

HQB18R

HQB24R

HQB30R

HQB36R

HQB48R

HQB60R

18''

24''

30''

36''

48''

60''

5-6x5

6-6x5

5-12x7

5-12x7

6-12x7

7-12x7

HIS Quad Block Rollers 1 Wheel Sheaves – Sizes and Radii

Wheel Diameter Actual Radius

1 ft 4 inches

1.5 ft 7 inches

2 ft 10 inches

One wheel sheaves

are categorized by

DIAMETER, not

RADIUS. Thus a 1

ft DIAMETER

sheave will have a

true RADIUS of only

4 inches.

A well lubricated (triplexed) cable.


80/109

Lubricating cable with a pump.Power driven lube pump.

Hand type lube pump.

Creative Cable Lubing

Homemade Mop & Coco Mat

Swivels

• Always use a swivel

• Swivels on basket grips (socks) do notrotate under load

• Ball bearing types are recommended

• The working load should be greater than themaximum allowable pulling tension

• Swivels that do not spin are NOTrecommended-some pulling line supplierssupply these to prevent twisting of theirwire rope or line.

Swivel Photo

Install with short end toward pulling line.


81/109

Basket Grip with Ball Bearing Swivel attached

Swivels that are part of the

Basket Grip do not spinwhen tension is applied.

Ball Bearing Swivel

Back-Out or Z-ing

• Cable that backs out of test hole on reel isreferred to as “Back-Out”.

• Caused by allowing loose winds to developon reel. Slight back-tension should be used.

• If cable is restricted at test hole, cable will bunch up on drum in a “Z” pattern, a.k.a. “Z-ing”.

• Also influenced by jacket type, drumtype/smoothness and cable stiffness.

•Cable “ acking Out” of the Reel

Eliminate the loose turns and reduce cable loss

“Roll This Way” – See Arrow

If rolled in this direction, cable gets tight,

wrong way loosens cable.

Z-ing


82/109

Z-ing

Z-ing

Z-ing

Z-ing

(knuckles)

No Loose Winds

Paying Off Bottom -Zero Backout


83/109

Equipment

Elaborate

Reel Brake

Using

Disc Brake

18

Simple Reel Brake/Tensioner

Tree Cable

Tree Cable

Summary• Pull thru max number of bends as early as possible

(when possible).

• Use sweeps with larger radius on difficult pulls to

minimize SWP .

• Use plenty of lube.

• Use BB Swivels.

• Dispose of a few feet of cable adjacent to basket

grip.

• If unsure of pull, perform a pulling tension calc in

both directions.

Available

as a binder

or CD


84/109

Pull-Planner ™

Cable Pulling

Software

A Program for Cable Pulling Tension Calculation

and Conduit System Design

DESCRIPTION

Pull-Planner ™ 3000 for Windows ™ calculates cable pulling tension and

sidewall pressure around bends using the pulling equations. Tension

estimates are useful in designing conduit systems and planning cable

pulls.

USE YOUR HEAD – WISELY – WHEN INSTALLING CABLE

Oops!!!

Reel Trouble

Conductor The conductor is really a

resistor. If you put ampsthru it, heat will be produced, but how much?

Conductor

Size

AluminumDC Resistance

@ 25ºC

(ohms/1000’)

Copper DC Resistance

@ 25ºC

(ohms/1000’)

#10 1.7 1.04

1/0 0.168 0.102

1000 0.0177 0.0108

Okonite EHB Table 1-3


85/109

Watts Generated by Conductor

#1 Al, at 90 C with 100 amps

R dc(ac) = 0.211 ohms/1000’ at 25Cadjust to 90C (EHB Table 1-4)

0.211 x 1.258 = 0.265

W = I2 x R

= 1002 x 0.265

= 5,300 watts/1000’

or

5.3 watts/ft (approx 5 – 100w light bulbs/1000’)

Chart of Ohmic Losses

#1 Al@90C w/Full Neutral Watts/ft Watts/1000 ftConductor Losses 5.66 5660

Neutral Losses 5.379 5379

Total Losses 11.04 1104

Equal to 11 – 100 watt light bulbs every 1000 ft.

Dielectric Losses (N-M Eq 36)

WD = 0.00276 x E2 x SIC x Pwr Factor

Log10 Di/Dc

= 0.00276 x (15/√3)2 x 2.9 x 0.0024

Log10 0.460”/0.90”

E = 0.0051 w/ft

D-Loss is negligible compared to Ohmic Losses

Chart of Losses w/ValuesTR-XLPE Okoguard (EPR)

Dielectric Losses 0.00007 0.00514

Conductor Losses 5.66 5.66

Neutral Losses 5.379 5.379

Total Losses 11.03907 11.04414

Difference 0.00507 watts/1000’

% Difference -- + 0.046/1000’

Therefore the difference is less than 5 thousandths of a watt

(or 5 hundredths of one percent) per 1000 installed feet per year.

Or a 0.0051 watt light bulb per 1000’

#1 Al, 220, Full Neutral, @13.8 kV, 90C


86/109


87/109

©3M 2008. All Rights Reserved.

1

Medium Voltage Accessories -

Sandy Cox

EMD Technical Service

Design, Standards, and Installation

3M Company


2

Agenda

Termination Theory & Design Considerations

Splice Theory & Design Considerations

Installation – What is critical?


3

Good cable prep is critical to the reliableoperation of any medium voltage accessory

– regardless of the manufacturer of thecable OR the accessory.


88/109


4

SHIELDED POWER CABLE

COMPONENTS

1. Conductor

2. Strand Shield

3. Insulation

Insulation Shield

4. Semi-conducting Layer

5. Metallic Shield

6. Jacket


5

Corona (Partial Discharge)


6


89/109


90/109


10

Semi-Con: Intended to shield the insulation from

the air that is between the insulation and metallic

shield


11

Metallic Shielding: Connected to ground and in

direct contact with semi-con


12

Jacket: Intended to provide physical protection

and keep moisture out of the cable


91/109


13

SPLICING & TERMINATING

“What Cable Info Do I Need?”

?

• Voltage Class (and insulation level)? _____________

• Conductor Size (and Copper or Aluminum)? ________________

• Cable Type (type of shield, armor, 3/C, etc.)?_______

• Location (indoor, outdoor, manhole, pole, etc.)? ____

• Other? ______________________________________


14

Definition of a Termination

To terminate a shielded power cable

means to discontinue, or end, its

insulation shield.

Semi-Conducting Shield Layer

Cable Shield Terminus


15

Functions of a Class 1 Termination(per IEEE-48 Standard)

To provide “Electrical Stress Control” for the

cable shield terminus.

To provide “External Leakage Insulation”

between the high voltage conductor and ground.

(Tracking protection.)

To provide a “Seal” against the environment, as

well as to help maintain the pressure, if any,

within the cable system.


92/109


16

I. Electric Stress Control forCable Shield Terminus

Stress Concentration

Near Cable Shield End


17

ELECTRICAL STRESS is the

concentration of electrical

potential (voltage) over a

defined distance.

TYPICAL UNITS: V/mil or kV/cm

Electrical Stress

When splicing or terminating, the

stress must be controlled and

minimized


18

A stress-cone is used to reduce the stress at the shield

discontinuity by extending the shield and gradually increasing

the thickness of insulation under the shield.

Geometrical Stress-Control


93/109


19

Dielectric (High-K) Stress Control

A device made with High-K (dielectric constant)

material is used to reduce stress at shield

discontinuity by field refraction due to the

difference in K values of two ne ighboring

dielectric layers.

©3M 200