cable pulling methods

For Hydro Ottawa Use Only © 2008 GCS0004 Rev.1 of 15

TITLE:

Engineering Specification

RECOMMENDED: K. McRoberts NO: 1 REV:

APPROVED: C. S. Malone P. Eng. OF

REV. DATE: 2008-12-03 GCS0004

15 1

XLPE CABLE INSTALLATION

15kV, 28 kV, 1000V AND 600V CABLES

See Hydro Ottawa’s Web site for the

Latest revisions at: www.hydroottawa.com


REVISION SHEET

Revision Description Date Initial

0 Original Document 2002-09-30 km/csm.

1 Sections added / Corrected Table 3-3 metric

SWBP RWU table added / 5-2 Ref. to

direct buried plant removed 2008-12-03 kh/km/csm


TABLE OF CONTENTS PAGE

1.0 INTRODUCTION............................................................................................................. 4

2.0 REFERENCE.................................................................................................................... 4

3.0 SCOPE ............................................................................................................................... 4

4.0 CABLE PULLING METHODS ...................................................................................... 4

5.0 PREPARATION ............................................................................................................... 5

6.0 LUBRICANT..................................................................................................................... 5

7.0 CABLE PULLING............................................................................................................ 6

7.1 ONE WAY PULL IN........................................................................................................... 6

7.2 ONE WAY FEED IN........................................................................................................... 8

7.3 TWO WAY PULL .............................................................................................................. 9

7.4 AFTER THE PULL............................................................................................................ 10

8.0 CABLE IDENTIFICATION ......................................................................................... 10

9.0 CABLE TRAINING ....................................................................................................... 10

10.0 CABLE RACKING ........................................................................................................ 11

11.0 SECONDARY SERVICES ............................................................................................ 11

APPENDIX A.............................................................................................................................. 12


1.0 Introduction

This specification covers the installation of primary voltage, 15kV & 28kV XLPE cables ranging

from 1/0 AWG aluminum/copper conductor through to 1000 kcmil aluminum conductor and

600V secondary aluminum triplex cables ranging from 1/0 AWG aluminum to 500 kcmil

aluminium/copper which comply with Hydro Ottawa Engineering Specification document

number GMS0005 and GMS0008. These cables shall be installed in a concrete encased duct and

manhole system, or a direct buried duct system. For cable pull in duct, the cable-duct

configuration shall be determined/approved by Hydro Ottawa.

2.0 Reference

Hydro Ottawa - ECS0002: 120/240V Underground Residential Meter Socket

Hydro Ottawa - GCS0012: Electrical Underground Distribution Plant Identification U/C

Hydro Ottawa - GMS0005: Underground Secondary

Hydro Ottawa - GMS0008: Underground Primary XLPE Concentric Neutral Cable

Hydro Ottawa - UTS0004: Single – Phase Padmount Transformer 2.4kV-16kV – Secondary

Wiring Detail

Hydro Ottawa - UTS0005: Single – Phase Padmount Transformer 2.4kV – 16kV – Primary

Wiring Detail

Prysmian – Handling and Installation Excerpt from Prysmian’s Wire and Cable Engineering

Guide

3.0 Scope

This specification covers how Hydro Ottawa and its contractors are to install underground cables

for Hydro Ottawa as well as maximum pulling tensions and sidewall bearing pressures.

4.0 Cable Pulling Methods

Cable that cannot be pulled in manually shall be installed by means of a cable puller, an electric

winch or a winch on a radial boom derrick. In each case, the machine operator shall have access

to a means of determining the pulling tensions on the cable (e.g. gauges which indicate direct

line pressure or gauges which indicate hydraulic pressure which can be converted to line tension

via a conversion table or a dynamometer). Cable pulling with trucks, backhoes or any other

method whereby the amount of pulling tension is not measurable, is unacceptable.


5.0 Preparation

First, establish the direction of the pull based on safe pulling tensions, sidewall bearing pressure

calculations and minimum bending radius for a Hydro Ottawa specific cable to be installed; see

Appendix A Tables 5-1, 5-2, 5-3, 5-4, 5-5A & 5-5B.

Based on the safe pulling tension, determine if the cable pull requires a basket grip or a pulling

eye attached to the conductor; see Appendix A Table 5-1. Basket grips or pulling eyes shall be

attached to the pulling rope or cable by an appropriate sized swivel head.

Rod each duct with an appropriate size brush and mandrel to ensure ducts are properly fitted and

they are clean and free of all dirt, stones, scale, water etc.

For installation in conduit, place cable guides wherever necessary to avoid abrasion and/or

damage to the cable e.g. when guiding the cable from the reel to the duct mouth or trench, when

passing through or exiting manholes, when exiting a duct run. Cable guides shall be in the form

of large diameter, smooth-surfaced free turning sheaves or rollers. They shall be designed to

ensure that cable will not ride off the end of the roller or be pinched into a sheave contour.

Guide tubes or chutes may be used provided they have a smooth burr-free working surface, well

flared entrances, largest possible bending radius and are securely fastened so that the cable

passes smoothly over them. In any case, equipment shall be installed to ensure the minimum-

bending radius of the cable is not exceeded; see Appendix A Tables 5-5A & 5-5B.

Using suitable reel mounting equipment, locate and position the reels such that cable tension at

the feeding end is minimized.

Select pulling equipment, which can provide smooth speed control at the anticipated tensions.

Ensure the pull rope or flat line has the required tensile rating. Avoid the use of elastic materials.

6.0 Lubricant

Pre-lubricate duct runs or setup lubrication points along the duct run (e.g. feed in point, manholes

etc to reduce pulling tension and abrasion to the cable jacket). For long heavy pulls, pre-

lubrication of conduit and pull rope is essential to prevent abrasion at the bends, particularly

plastic conduit bends, which can become softened due to frictional heating. In the case of long

duct lengths or excessive curvatures in the duct the cable may have to be pulled in from two

directions.

The recommended amount of lubricant is depended on the size and length of the conduit system

into which the cable is being pulled. Typically, a ratio of 6.4 liters of lubricant per 100 linear

meters of 100 mm PVC duct would be used.

Hydro Ottawa will accept water-based Bentonite Clay lubricants. Compounds containing oils or

greases are not acceptable since they can adversely affect the cable jacket. The following chart

provides a list of pulling lubricants, which are acceptable to Hydro Ottawa. Lubricant not shown

on this chart, shall not be used without prior approval by Hydro Ottawa.


TABLE 6-1 Cable Pulling Lubricants

Product Trade Name Manufacturer

Polywater J American Polywater Corporation

Cable Glide CRC Industries

7.0 Cable Pulling

Poly rope is not to be used for any mechanical pulling (e.g. conductor/winch line, overhead or

underground). Poly rope stretches when subjected to high tension and can create a hazard.

Manual pulling (by hand) using poly rope is allowed.

When using a mechanical means to complete a pull, (e.g. capstan, collapsible wheel, clutch-able

capstan, boom, vehicle), a Samson rope or equivalent, flat line, shall be used, as it does not

stretch in the same way that poly rope does, and presents less of a hazard.

Provide two-way voice communication and adequate resources at both feeding and pulling ends

of the run and at any interim location (e.g. manhole). Apply pulling lubricant liberally during the

cable pull.

To minimize back reel tension accelerate slowly and smoothly from rest to a constant pulling

speed of approximately 30 m/minute. Avoid stopping the pull midway through the installation;

the drag due to friction is greatly increased when pulling is restarted.

Record dynamometer readings at frequent intervals during each pull.

7.1 One Way Pull In

Position the pulling equipment at the pulling manhole or transformer base. Set up

equipment to maintain the minimum-bending radius of cable being pulled. See example

in Figure 7-1 and Figure 7-2.


Figure 7-1 Pull End Setup for XPLE cable – Transformer Base

Figure 7-2 Pull End Setup for XLPE cable – Manhole


7.2 One Way Feed In

Position the cable reel so that the cable can be handfed into the manhole. When possible

the cable shall be pulled off the reel by hand to reduce pulling tensions; see Figure 7-3 and Figure 7-4.

Figure 7-3 Reel End Setup for XPLE cable – Transformer Base

Figure 7-4 Reel End Setup for XLPE cable – Transformer Base


7.3 Two Way Pull

Position the cable reel near the center of your pull and pull required cable one way

according to all tension guidelines and pertinent specifications; see Figure 7-5.

Figure 7-5 Initial Setup for 2-way Pull

Back reel cable length required for pull in other direction on debris free ground or a tarp

in a coil formation, large enough to not exceed minimum cable bending radius; see

Figure 7-6.

Figure 7-6 Back reel cable in a coil formation

Position puller at pulling end and begin pulling. Maintain slack loop of cable at feed end

into duct structure; see Figure 7-7.


Figure 7-7 Final Setup for 2-way pull

7.4 After the Pull

Seal the ends of the installed cable and the ends of unused cable remaining on the reel,

pending splicing or terminating, to prevent ingress of moisture.

Observe the minimum-bending radius when training cable into final position. Secure

cables to manholes, riser poles, etc., as per Hydro Ottawa Engineering Specifications.

Provide suitable mechanical protection during project construction for exposed cables.

8.0 Cable Identification

All cables shall be identified as per Hydro Ottawa specifications GCS0012, UTS0004, UTS0005,

and ECS0002.

9.0 Cable Training

At transformer bases and primary pedestals, primary cables shall be trained from the bottom of

the base to the elbow insert. Care should be taken in order to install elbow compression

connectors with the proper turn to fit the insert, cables are not crossed or tangled with adjacent

cables. Freedom of movement for energized switching operations is essential; see Hydro Ottawa

Engineering Specification UTS0005.

Secondary cables shall be trained from the bottom of the transformer base to the secondary bus

of the transformer with care taken to ensure cables are not crossed and do not cause a downward

force on the transformer bus bars; see Hydro Ottawa Engineering Specification UTS0004.


10.0 Cable Racking

Hydro Ottawa shall determine the cable racking method and location to be used. Cables in

manholes and switchgear bases shall be racked along the wall of the structure using Hydro

Ottawa approved tray and support system. The minimum bending radius of cables shall not be

exceeded; see Appendix A Table 5-5A & 5-5B.

11.0 Secondary services

Secondary cables are to be pre-installed to lot lines staked up to a suitable support (1 m onto

private property with a minimum 2 m of cable tail) and their ends sealed with Self-

Amalgamating Polyethylene (SAPP) tape to prevent the ingress of moisture.

F

or

Hyd

ro O

ttaw

a U

se O

nly

© 2

00

8

GC

S0

00

4 R

ev.1

P

age

12

of

15

AP

PE

ND

IX A

T

ab

le 5

-1 -

Ma

xim

um

Ca

ble

Pu

llin

g T

ensi

on

s

Pri

ma

ry V

olt

ag

e C

ab

les,

PV

C J

ack

et, X

LP

E I

nsu

lati

on

Maxim

um

Pu

llin

g T

ensi

on

Bask

et G

rip

P

ull

ing E

ye

Sin

gle

Con

du

ctor

Pu

ll

Th

ree

Con

du

ctor

Pu

ll*

Sin

gle

Con

du

ctor

Pu

ll

Th

ree

Con

du

ctor

Pu

ll**

Con

du

ctor

Siz

e&T

yp

e

Pou

nd

s K

ilogra

ms

Pou

nd

s K

ilogra

ms

Pou

nd

s K

ilogra

ms

Pou

nd

s K

ilogra

ms

1/0

AW

G C

opper

1,1

60

526

2,3

20

1,0

52

1,1

60

526

2,3

20

1,0

52

1/0

AW

G A

lum

inum

845

383

1,6

90

767

845

383

1,6

90

767

2/0

AW

G A

lum

inum

1,0

65

483

2,1

30

966

1,0

65

483

2,1

30

966

500 K

cmil

Copper

5,5

00

2,4

95

10,0

00

4,9

90

5,5

00

2,4

95

11,0

00

4,9

90

500 K

cmil

Alu

min

um

4,0

00

1,8

14

8,0

00

3,6

29

4,0

00

1,8

14

8,0

00

3,6

29

750 K

cmil

Alu

min

um

6,0

00

2,7

22

10,0

00

4,5

36

6,0

00

2,7

22

12,0

00

5,4

43

1000 K

cmil

Alu

min

um

8,0

00

3,6

29

10,0

00

4,5

36

8,0

00

3,6

29

16,0

00

7,2

57

* T

ensi

ons

are

for

1 b

ask

et g

rip p

er c

ondu

ctor

** T

ensi

ons

are

for

1 p

ull

ing e

ye

per

condu

ctor


APPENDIX A (con’d)

Table 5-2 Maximum Cable Pulling Tensions

Secondary Voltage Cables, 600V, XLPE Insulation

Maximum Pulling Tension

Basket Grip Pulling Eye

Single Cable Pull* Single Cable Pull** Conductor Size & Type

Pounds Kilograms Pounds Kilograms

1/0 AWG Aluminum URD 1,690 767 1,690 767

3/0 AWG Aluminum URD 2,000 907 2,684 1,217

250 Kcmil Aluminum URD 2,000 907 4,000 1,814

500 Kcmil Aluminum URD 2,000 907 8,000 3,629

* Tensions are for 1 basket grip per triplexed cable

** Tensions are for 1 pulling eye per conductor

Table 5-3 Maximum Cable Pulling Tensions

Secondary Voltage Cables, 1000V RWU

Maximum Pulling Tension

Basket Grip Pulling Eye

Single Cable Pull* Single Cable Pull** Conductor Size & Type

Pounds Kilograms Pounds Kilograms

2 AWG RWU Copper 1458 660 1458 661

2/0 AWG RWU Copper 2000 907 2928 1328

4/0 AWG RWU Copper 2000 907 4654 2111

350 Kcmil RWU Copper 2000 907 7700 3493

500 Kcmil RWU Copper 2000 907 11000 4990

* Tensions are for 1 basket grip per triplexed cable

** Tensions are for 1 pulling eye per conductor


Table 5-4 Maximum Sidewall Bearing Pressure

Primary Voltage Cables, PVC Jacket, XLPE Insulation

Sidewall Bearing Pressure Conductor Size & Type

Lbs/Ft of Bend Radius Kg/m of Bend Radius

1/0 AWG Copper 1,160 1726

1/0 AWG Aluminum 845 1258

2/0 AWG Aluminum 1,065 1585

500 Kcmil Copper 2,000 2976

500 Kcmil Aluminum 2,000 2976



URD Aluminum 1200 1786

RWU Copper 1200 1786

Table 5-5A Minimum Bending Radius (MBR) During Installation*

Primary Voltage Cables, XLPE Insulation

Conductor Size & Type Minimum Bending Radius

(mm)

Minimum Bending Radius

(inches)

1/0 AWG Copper, 15 kV 354 14

1/0 AWG Aluminum, 28 kV 411 16


500 Kcmil Copper, 15 kV 506 20

500 Kcmil Aluminum, 28 kV 564 22



*Based on 12 x Cable Diameter


Table 5-5B Minimum Bending Radius (MBR) Permanent*

Primary Voltage Cables, XLPE Insulation

Conductor Size & Type Minimum Bending Radius

(mm)

Minimum Bending Radius

(inches)

1/0 AWG Copper, 15 kV 236 9



500 Kcmil Copper, 15 kV 337 13




*Based on 8 x Cable Diameter

cable pulling methods

Documents

reel end setup

pull end setup

conductor size

minimum bending radius

bending radius

1 pulling eye

5a

poly rope