7/29/2019 OHE I

1/41

M2.11/15 1

TYPES OF OHEs

Conductors,

Cantilevers and Structures.

Course On Traction Distribution Session No.M2.11/15

TITLE - OHE I Page 1 of 41

Rev . 0. Date of issue 12.2.2009

7/29/2019 OHE I

2/41

M2.11/15 2

The electrical conductors over the track

together with their associated fittings,

insulators and other attachments by meansof which they are suspended and registered

in position.

All overhead electrical equipment,distribution lines, transmission lines, and

feeder may be collectively referred to as

overhead lines.

OHE

7/29/2019 OHE I

3/41

M2.11/15 3

TRAMWAY TYPE OHE Regulated

SIMPLE OHE Un Regulated

7/29/2019 OHE I

4/41

M2.11/15 4

SIMPLE OHE Regulated

SIMPLE OHE Regulated

7/29/2019 OHE I

5/41

M2.11/15 5

SIMPLE OHE Regulated

STICHED CATENARY OHE

7/29/2019 OHE I

6/41

M2.11/15 6

GENERAL ARRANGEMENT OF OHE

7/29/2019 OHE I

7/41

M2.11/15 7

COUNTER WEIGHT

GUY

RODGU

RO

GUY

ROD

GUY

ROD

ANTICREEP WIRE

(19/2.5 G.S) 93sq.mmIN SPAN

JUMPER(AC)

(19/1.8)TERMINATION

OF REGULATED

OHE CATENARY

WIRE CdCu

65sqmm (19/2.1)

CONTACT WIRE

107 sqmm

REGULATING

EQUIPMENT

PULLEY BLOCK

TYPE

TERMINATION

OF REGULATED

OHEAXIS OF

MAST

350 Mtrs. ( MAX)

DIRECTION OF TRAFFIC

SCHEMATIC ARRANGEMENT OF REGULATED OVER HEAD EQUIPMENT

(RDSO Drg.No. ETI / OHE / G / 02101)

7/29/2019 OHE I

8/41

M2.11/15 8

OHE Conductors

Catenary Wire

Contact Wire

Dropper Wires

Jumpers

Feeder/Return Conductor

Large Span Wire

Earth Wires

7/29/2019 OHE I

9/41

M2.11/15 9

OHE CONDUCTORS

CATENARY WIREDESCRIPTION Cd - Cu Al.

SIZE MM 19/2.1 19/2.79

DIA. MM 10.5 13.95AREA SQ.MM 65 116

CONDUCTIVITY 80% 52%

CU.EQUI.SQ MM 52 60

BREAKING STRENGTH kgf 3920 3300WT/M 0.6KG 0.32KG

RESISTANCE/KM 20C 0.336 0.288

BRIDLE WIRE 7/2.1

Al. - ALL ALUMINIUM ALLOY

7/29/2019 OHE I

10/41

M2.11/15 10

OHE CONDUCTORS

16.40.15

16.40.15

7045

DESCRIPTIONRDSO SPEC ETI/OHE/4 2

DC

MATERIAL

CONTACTWIRE

HIGHTRAFFIC DENSITY

HD-CU HD CU

AREA SQ. MM 107 150 193

SIZE MM 12.24 .16 14.50 .20

SHAPE

HD CU

GROOVED G.R G.R

DIA MM 12.24 .16 14.50 .20

BREAKING

STRENGTH KGF 3905 5475

0.9512WEIGHT/M Kg 1.334 1.716

Contact Wires

7/29/2019 OHE I

11/41

M2.11/15 11

OHE ConductorsType of conductor Feeder/RC Large span

Wire(130)

Small

Jumper(50)

Large

Jumper(105)

Material HD-Cu Cd-Cu Annealed Cu Copper

No. of strands 37 37 19 133

Dia.of each str. 2.25 2.10 1.83 1.013

Dia.of conduct. 15.75 14.70 9.14 15.20

X-sec area (mm2) 147.10 125.6 48.98 107.3

Cu equivat.(mm2) 144 102 48 103

Wt. (Kg/m) 1.326 1.1692 0.952 0.982

Normal Tension-kg 1000 2000 nil nil

Breaking load-kg 6080 7650 1130

Safe wkg. Load -kg 2026 2550/1915 317

Factor of safety 3 3 3

7/29/2019 OHE I

12/41

M2.11/15 12

OHE ConductorsType of conductor Small

Dropper(5m

m)

Large

Dropper (7

mm)

Earth Wire(50) Eart

Wire(galvani

zed steel)

Material HD-Cu HD-Cu ACSR Racoon Galvan. steel

No. of strands 1 1 6/1 19

Dia.of each str. 5 7 4.9 2.5

Dia.of conduct. 5 7 12.27 12.5

X-sec area (mm2) 19.64 38.48 77.83 for ML 93.3

Cu equivat.(mm2) 19 38 48 ----

Wt. (Kg/m) 0.1746 0.3421 0.318 0.7341Normal Tension-kg 320 1000

Breaking load-kg 825 1530 2746 6100

Safe wkg. Load -kg 275 510 915 2033

Factor of safety 3 3 3 3

7/29/2019 OHE I

13/41

M2.11/15 13

COMPARISON AC-DC OHE

DESCRIPTION 25 KV AC 1500 V DC

1. CATENARY SIZE 19/2.1 37/2.92 mmAREA 65 sq.mm 242 sq.mm

WEIGHT/METER 0.602Kg 2.265KgDIA 10.5 mm 20.44 mm

2. CONTACT SIZE DIA 12.24 0.16 16.40 0.15AREA 107 sq mm 193 sq mm

WEIGHT/METER 0.052 Kg 1.721 KgCONDEMNING DIA 8.25 mm 8.89 mm

3. DROPPER DIA 5 mm 7mm

CONDEMNING AREA 74 sq mm 100 sq mm

WEIGHT 0.1746 Kg 0.3421 Kg

7/29/2019 OHE I

14/41

M2.11/15 14

DESCRIPTION 25 KV AC 1500 V DC

4. TENSION CATENARY 1000Kg 800 KgCONTACT 1000Kg 1400 Kg

REGULATED UNREGULATED

5. SPAN (MAX) 72 METER 67.5 M(220 Ft)

6. RESISTANCE 0.1699 0.0936

1 KM CONTACT

AND RAIL 0.70 0.0685

7. NET RESISTANCE

COMPARISON AC-DC OHE

1 KM OHE 0. 41

BT & RC

7/29/2019 OHE I

15/41

M2.11/15 15

COMPARISON AC-DC OHE

SYSTEM TOTAL

25 KV AC

CONTACT CAT.

107 65(19/2.1) 159

1500 V DC 193 242 435

BB VT- KALYAN C.RLY. (37/2.92)

CCG - VR W.RLY.

1500 V DC 193 323 MAIN

KALYAN - IGP (37/2.25)

KALYAN - PA 129 AUX

(19/2.95) 645

TGR 2 (KASARA) 193 323 + 323 968

-- IGP (DN LINE) 129 (AUX.)

7/29/2019 OHE I

16/41

M2.11/15 16

Dropper

Assembly

A fitting used in

overhead equipment

construction for

supporting the

contact wire from

catenary

7/29/2019 OHE I

17/41

M2.11/15 17

DROPPER

MATERIAL HARD DRAWN COPPER

IS 282 / 1982

SMALL LARGE

DIA( MM) 5 7

AREA(SQ MM) 19.64 38.48

DROPPER SPACINGFIRST & LAST 2.25M

INTERMEDIATE 9 M

BETWEEN FIRST & SECOND

9 M FOR SPAN = 9 N+4.56.75 M FOR SPAN = 9 M

WT(Kg/m) 0.1746 0.3421

7/29/2019 OHE I

18/41

M2.11/15 18

Catenary Dropper Assembly

7/29/2019 OHE I

19/41

M2.11/15 19

Jumper

A conductor or an arrangement of conductors for

electrical continuity not under tension, which forms

electrical connection between two conductors orequipments.

1. F Jumper( insulated overlap span,N/S-OOR ; 50 mm2 )

2. G Jumper( Uninsulated O/L,T/O,X/O ; 105 mm2

)

7/29/2019 OHE I

20/41

M2.11/15 20

Cantilever assembly

It is an insulated swivelling type structural

member, comprising of different sizes of

steel tubes, to support and to keep theoverhead catenary system in position so

as to facilitate current collection by the

pantograph at all speed without infringing

the structural members. It consists of thefollowing structural members :

Stay , Bracket , Register Tubes and

steady arm

C til A bl

7/29/2019 OHE I

21/41

M2.11/15 21

1) MAST FITTING FOR ST INSULATOR

2) STAY TUBE INSULATOR

3) TUBLAR STAY ARM

4) STANDARD / LARGE BRACKET

5) REGISTER ARM

6) STEADY ARM

7) BRACKET INSULATOR

8) MAST FITTING FOR BT INSULATOR

9) CATENARY SUSPENSION BRACKET

10) REGISTER ARM HOOK

11) DROP BRACKET

12) ANTI WIND CLAMP

13) INCLINED DROPPER

14) SUSPENSION CLAMP

15) CONTACT WIRE SWIVEL CLIP

16) TUBLAR STAY SLEEVE

17) TUBLAR STAY ADJUSTER

18) TUBE CAP

18

Cantilever Assembly

7/29/2019 OHE I

22/41

M2.11/15 22

Cantilevers on Platforms

Cantilevers

On high level

Platform

On low level

PlatformOn Rail level

Platform

RT extension chair

ST insulator to be clear off

platform

Bracket chair

Stay arm chair

7/29/2019 OHE I

23/41

M2.11/15 23

At Anti creep center

Suspension Bracket

CATENARY SUSPENSION BRACKET

7/29/2019 OHE I

24/41

M2.11/15 24

Types of Structures

Classification as per Manufacturing Process

Rolled : BFB , RSJ

Fabricated : K and B types Concrete Masts

Classification as per no. of Tracks

Single structures : Masts Two Track Cantilever Structures : TTC

Multi Track Structures : Portals , Head Spans

7/29/2019 OHE I

25/41

M2.11/15 25

N type Portal

O type Portal

R type

Portal

G type

Portal

P type Portal

7/29/2019 OHE I

26/41

M2.11/15 26

Masts

Mast : A single vertical post embedded in thefoundation or otherwise rigidly fixed in verticalposition to support the overhead equipment

with cantilever assembly. It may be rolledsection or fabricated. The uprights of portalsand TTCs are also called mast.

Setting Distance (Implantation) : Thehorizontal distance from the nearest face oftraction mast to the centre line of the track.

7/29/2019 OHE I

27/41

M2.11/15 27

Selection of MASTS

The masts for standard applications viz. masts for single OHE,

anti-creep and overlaps should be selected from the mastemployment schedules. Separate mast employment schedules

have been made for each wing pressure zone as under:

Conventional OHE ( 65mm2 Cd-Cu catenary and 107 mm2

copper contact wire)Light wind pressure Drg. No. ETI/C/0702

( 75 Kgf/m2) Sheet 1 to 5

Medium wind pressure Drg. No. ETI/OHE/G/00153

(112.5 kgf/m2) and 00154, sheet 1 to 4

Heavy wind pressure Drg. No. ETI/C/0726

( 150 Kgf/m2) Sheet 1 to 4

ETI/C/0727,0728 and 0729

7/29/2019 OHE I

28/41

M2.11/15 28

Selection of MASTS

The mast employment schedules are prepared only

for standard setting distance as given in Drg. No.

ETI.OHE/G/00111 Sh. 1 For higher implantations and

other locations like masts for turnouts, diamondcrossings, umbrella type OHE etc, the load on the

mast should be calculated separately for every

locations and safety of the mast checked in

accordance with Drg. No. ETI/OHE/G/00141 sheet 3.The permissible bending moments of the mast are

given in Drg. No. ETI/SK/C/122

7/29/2019 OHE I

29/41

M2.11/15 29

TTC

In the yards and sidings when the mast cannot be

erected near the track to be equipped, it may be

erected spanning one or two tracks using a two trackcantilever (Drg. No. ETI/C/009, Sheet 1). This is

generally used for supporting OHE near turnouts and

X-overs. This arrangement should not be used for

supporting OHE of two main lines. The OHE can besupported upto a distance of 10.5 m from the upright

with this arrangement.

7/29/2019 OHE I

30/41

M2.11/15 30

TTC

TTC Arran ement

Drop Arm

TTC Mast

Boom

Drop Arm

7/29/2019 OHE I

31/41

M2.11/15 31

PORTALS

On multiple track sections, where adequatetrack centres are not available and trackscannot be slewed, portals are used. Eachportal consists of two fabricated uprights and

one fabricated boom consisting of with orwithout one central piece and two end pieces.

6.3.1 : Three types of portals have been

standardized. N type portal is used for clearspans of 10 m-20m (4 track maximum), O typeportal is for clear span of 20m-30m( for 6 tracksmaximum) and R type portal with span of

30m-40m (for 8 tracks maximum).

PORTALS

7/29/2019 OHE I

32/41

M2.11/15 32

PORTALS

6.3.2 Where the upright of standard portals cannot be

erected due to limited track centres, P type portal may beused in place of N type and G type may be used in place

of O type. The width of upright of these portals is 300 mm

and 250 mm as against 450 mm of N type and 550 mm of

O type respectively. In exceptional cases, BFB uprights

of 152 mm width (Drg. No. ETI/C/0026 Sheet 1) may also be

used with N type portal boom. Special BFB portals with 3

legs (Drg. No. ETI/C/0027 Sheet ) may also be used in

exceptional cases where N type portal can not be used.

6.3.3 The cantilevers for the extreme track are providedon the uprights of the portals. The cantilevers for the

intermediate tracks are provided on the drop arms

suspended from the boom.

S G S C

7/29/2019 OHE I

33/41

M2.11/15 33

2800 mm TANGENT TRACK

INSIDE CURVE RADIUS

3200 mm UP TO ABOVE 3500 M

3350 mm TO 3500 TO 2350 M

3550 mm TO 1 2350 TO 1150 M

3600 mm 1 TO 6 1150 TO 300 M

OUTSIDE CURVE RADIUS2800 mm UP TO 2 >/ = 875 M

2950 mm ABOVE 2 < 875 M

3000 mm PORTALS, HEADSPAN LEG, MASTCARRYING TWO/THREE OHES. ADD 500 mm over

above values for single masts.

4750 mm ON PLATFORMS

SETTING DISTANCE

7/29/2019 OHE I

34/41

M2.11/15 34

SPAN

Suspension Distance:The horizontal distance fromthe centre of the eye of catenary suspension bracketto the face of the mast for a single cantilever assemblyor to the face of cross arm channel in case of multiple

cantilever assembly.Span:The distance between the centre lines of theadjacent supporting masts for overheadequipment/lines.

Clear span in case of portal structure, is the distancebetween the inner faces of portal uprights.

7/29/2019 OHE I

35/41

M2.11/15 35

SPAN

Spans shall be accurately measured by

means of a steel tape. On curves, these

measurement shall be taken on the outer railof the middle track in the case of an odd

number of tracks and in the case of an even

number of tracks on the inner rail of the first

outside track (from the centre of theformation). On single track, measurements

shall be made on the outer rail.

SPAN CHART

7/29/2019 OHE I

36/41

M2.11/15 36

MAX. SPAN 72 MMIN. SPAN 27 M

SPAN IN MULTIPLE OF 4.5

SPAN CHART

72 58.5 45 31.5

67.5 54 40.5 27

63 49.5 36

TWO CONSECUTIVE SPANS SHALL NOT

DIFFER MORE THAN 18 M

SPAN CHART

St d d S

7/29/2019 OHE I

37/41

M2.11/15 37

Standard SpanStandard spans shall be determined in accordance

with:

i) Drg. No. ETI/OHE/G/00202 for conventional OHE.

ii) Drg. No. ETI/OHE/G/04201 for regulated tramway

OHE and

The spans shall be as large as practicable, but shouldenable the contact wire to be erected with permissible

stagger. For a stipulated maximum stagger, the

length of the span is governed by curvature, blow off

of overhead equipment, sway of pantograph anddeflection of the mast under wind condition. Standard

spans shall be used to maximum extent possible.

Restrictions on SPANS

7/29/2019 OHE I

38/41

M2.11/15 38

Restrictions on SPANS

The following restrictions are applicable.

i) On main tracks, the lengths of two consecutive spans shall

not normally differ by more than 18 m.

ii) The length of spans with unequal encumbrances shall be

such that the axial distance between the catenary and the

contact wire at the minimum dropper is not less than 150 mm.

For example the length of the span with 1.4 m and 0.9 mencumbrances at the two ends shall not exceed 67.5 m. This

restriction is applicable to the two spans on each side of the

structure, equipping a turnout for the main OHE.

iii)Spans in the vicinity of over line structures with restrictedhead room shall be determined with reference to the electrical

clearances available (See para 3)

Restrictions on SPANS

7/29/2019 OHE I

39/41

M2.11/15 39

Restrictions on SPANS

The following restrictions are applicable.

iv)The lengths of spans loaded with section insulatorsmay require to be restricted (See para 11)

v)Non-standard spans may be adopted in difficult

locations, e.g. in rocky cuttings, on through girder

bridges, for locations of masts on bridge piers andwithin station limits.

vi) With crossed type equipment with actual crossings

of OHEs at facing turnouts, the anchor spans shall berestricted to 54 m.

vii)Where earth wire is provided, the maximum span

over level crossings should be 58.5m.

STAGGER

7/29/2019 OHE I

40/41

M2.11/15 40

STAGGERStagger of the contact wire is the horizontal distance of the

contact wire from the vertical plane through the centre of

pantograph plan at the contact surface. 200mm (tangenttrack), 300 mm (curved track)

The stagger of the catenary is the horizontal distance of theeye of the catenary suspension bracket from the verticalplane through the centre of the track.(catenary stagger is the

displacement of catenary wire from the centre of track)

Mid span stagger

Where the two adjacent spans are located on curves ofdifferent radius or when the two versines are in opposite

directions, the spans shall be determined so as to keep themid span stagger in the two spans within the limit given inthe span and stagger chart (ETI/OHE/G/00202), taking intoaccount the stagger at the common support and the stagger

at the extreme supports .

7/29/2019 OHE I

41/41

M2 11/15 41

Thanks