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RELIANCE

PROJECT TITLE:

R E L I A N C E

J A M N A G A R E X P O R T R E F I N E R Y P R O J E C T

Siemens Ltd. I

DOCUMENT TITLE: RATING & SHORT CIRCUIT CALCULATION FOR MEDIUMVOLTAGE SWITCHGEARj

VENDORS DOCUMENT NO: (4) - G71570 - U5227 - ZlO4.,

VENDORS REVISION NO: A

Supplier Document Review

Penn ission to proceed does not cons tit ute acceptance or approva l of Desi gn De lan, Ca lcul ations , Analysis , Tes t Melhods or Matena ls developed OR selected by SUPPLIER , and does

NOT rel ieve SUPPLIER from FULL compl iance with Contractual Obl igat ions

.' Work May Proceed

D2a Revise & Resubmi t. Work may Proceed o2b Revise - Work may Proceed do not

subject to incorporation of changes resubmit until final

0 Revise & Resubmit . Work may not Proceed

0 Review not requir ed . Work may proceed

By: Chandrashekar Shri~an Date: 21-03-2007

Discipline: Electrical I IES-AVZ200-35,ES-RDZ300-0ffOZ,ES-RKZ300-0fES-RFZ400-0f,ES-RHZ400-0f,ES-RHZ500-01/D2,ES-RWZ600-0f,ES-RWZ600-02,ES-UUZ700-01,ES-UUZ700-

02,ES-UUZ700-09,ES-RH300-17,ES-RHZ300-50,ES-RHZ300-60,ES-RFZ400-30,ES-RFZ400-3f ,ES-MMB00-51 ,ES-MM800-61,ES-BBZ951-01 ,ES-BBZ951-02,ES-

Equipment No, B8Z951-03

MRNo_

I E I s i o i L l o l 1 1

PO No_ Unit No. Cal No. Seq_No. Rev_ No.

2 5 1 9 4 I J I G I Z I I E I S I 0 i L l 0 1 1 1 I M I A I 1 1 0 1 0 1 0 1 I E l o l 1 1 1 0 1 0 1 0 1 1 1 ~

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Procedure for carrying out amendments

1. Total no. of sheets, pertaining to a Drawing No. are mentioned only on Sheet No.1 and on last sheet.

1 2 3 4 5 6 7 8 9 ]0 II 12 13 14 15 16 17 18 19 20 21

2.( ) 1 1 1 1 1 1 1 - ~ 1 1 1 1 1 1 1 1 1 1 C D 1 - 1 1 1 1

Alphabet in the 1st square, of the 4 Block of squares, indicates latest amendment or the status of the issue of the drawing.

3. In case of changes, the amendment to Drawing No. will be carried out only on those sheet, in which changes have taken place

and on Sheet No. 1 for the purpose of summary of amendments. The same procedure will continue for subsequent changes but

every additional change will be indicated by use of next alphabet.

e.g. Say amendment 'A' takes place in Sheet No. 3,4,7. Then alphabet 'A' will appear in 1st square of 4th Block of DrawingNo..Written on Sheet No. 3,4,7 & 1. Further, say, next amendment takes place in Sheet No. 3,5,9. Then alphabet 'B' will

appear in 1st -square ofthe 4th Block of Drawing No. Written on Sheet No. 3,5,9 & 1. Even though Sheet No.5 & 9 do not have amendment

'A' earlier, they directly will have amendment 'B'.

4. Separate tabular form of amendment column does not appear on Sheet No. 1 but does appear on all remaining sheets. The brief

description in these columns indicates the reference of Client's/Sales Office's/Work's letter or actual changes done in the

drawing. The date-column indicates when the amendment has been carried out. TIle actual and latest changes are highlighted by

drawing a circular shape around them and by writing amendment-alphabet in a triangle near this circular form.

5 . Reference Drawing Nos. wherever mentioned, shows basic Drawing Nos. without any amendment The information about the

latest issue of any drawing can be obtained only from latest copy of 'List of Documents' which is sent along with set of drawings

for every drawing submission

Index Summary of Amendments Date Drawn Checked

A As Commented 23.1.07 BBP BBPVB

C

D

E

F

G

H

I

J

K

L

M

N

0p

QR

S

T

U

V

W

X

Y

Z

Client: MIS. RELIANCE PETROLEUM LTD. Sales Ref: -3000554079Project: JAMNAGAR EXPORT REFINERY PROJECT

Consultant: BECHTEL FRANCE S.A.S

Date: 18.01.07 Description :- 6.6kV Switchboard ShNo.

Prep: MG /Ckd: BBPY_ Work :- 8BK80 - 3AB VCB

A As commented 23.01.07 BBP Siemens Ltd.Issue Remarks Date Name PTD-M/SOE Details:- RATING &SHORT

OFFICECIRCUIT CALCULATION FOR

MIDIUM VOLTAGEBECHTEL PROJECT SPEC. REF:25194 - 3PS ES -002

(4) - G71570 - U5227 - Zl04 ,

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SIEMENSLTD

PTO M I PO

PRODUCT

8BK80-12 kV

600/800W

CALCULATION FOR CONTINUOUS CURRENT

CARRYING CAPACITY

Client: - Rll-JERP. (W.O. no.3000554079)

Project : JERP -JAMANGAR; 6.6kV Medium Voltage SwitchboardConsultant . Mis Bechtel S.A.S .'

Data Outside Ambient Temperature ( TA) :

End Temperature Limit on connections (T2) :

400C

115 ~C IEC60694

(2002) attached

3000A

Al (Ag plated)

3x160xlOmm

Desired Current Rating

Main busbar Material

Main Busbar Cross Section

Reference DIN 43670 is referred to obtain the basic current rating CIA) of the busbars used

and derating factors (K1, K2, K3, K4 and K5 ) for calculating the in - panel

rating.

Configuration : As per standard layout of SBKSO-800w

Ratings, Factors and Calculations

a) IA, basic rating of the busbar (3x160xl0 Al Blank) selected as per DIN 43670 at reference ambient

temperature of35 0C around busbars and end temperature of65 0C IA = 4000A

(DIN 43670Page 3 attached)

b) Kl, conductivity factor for Electrolytic grade Aluminium as per IS with a conductivity of 35.1 illI

ohm mm sq. is 0.998 (DIN 43670Page 7 attached)

c) For calculating K2, which is the factor for ambient temperature around busbars and temperature on

the same other than 35 0C and 65 °C respectively we need to know the temperature of the air around

busbars.

Based on the formulae, characteristics, heat dissipation curves, etc. given in the

" Erwaermungen in Schraenken ( Temperature rise in panels )" manual of our principals, Siemens

AG, the temperature difference between the air outside the panels and air surrounding the connection (

TD ) is estimated to be 15 OK

The temperature of air around busbars

Tl = TA+ TD

= 40+ 15 =55 °C

From the graph (DIN 43670Page 7 attached) in the above DIN, for T1 =55 0C and

T2 = 1150 C,

K2 =1.4

Calculation Record

No.

(4) - G71570 - U5227 - Z104

Dept.:PTD - M /

PD

Prep. By :Pranoti Chkd. By: VMG ,,~

'\;

Page 1 of 2

Client: MIS. RELIANCE PETROLEUM LTD.

Project: JAMNAGAR EXPORT REFINERY PROJECT

Consultant: BECHTEL FRANCE S.A.S

Sales Ref: -3000554079

1--_-l- +-__ I--_-+_D_at_e_:_18_._Ol_.O_7_-lescription :- 6.6kV Switchboard

Prep: MG IShNo.

Ckd: BBP VWork :- 8BK80':" 3AH VCBI----l--------~~~I----+-------~~A As commented 23.01.07 BBP Siemens Ltd.

Issue Remarks Date Name PTD-MfSOE.OFFICE

Details:- RATING &SHORT

CIRCUIT CALCULATION FOR

MIDIUM VOLTAGEBECHTEL PROJECT SPEC. REF:25194 3PS - ES - 002

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SIEMENSPTD-M/PD

PRODUCTSBKSO-12kV

600-S00WOW

CALCULATION FOR CONTINUOUS CURRENT

CARRYING CAPACITY

d) K3 is derating factor which is applicable only if the connection are laid horizontally ( i.e. the larger

dimension in a horizontal plane) or if the busbars run vertically for a length of more than 2m. K3 =

1

e) K4 is the derating factor applicable for AC upto 60 Hz if spacing between busbar lamination is less

th811the busbar thickness and is applicable only if there is no tapping on busbars in a length of 2m.

K4 1

f) K5; Factor for higher altitudes is reproduced from the above DIN

Attitude above msl in m K5 (INDOOR) K5(OUTDOOR)

10002000

3000

4000

K5 = 1.0

1.000.99

0.96

0.90

0.980.94

0.89

0.83

g) I, the calculated ratings of bus bars chosen

I = IA * Kl * K2 * K3 * K4 * K5

= 4000 * 0.998 * 1.4 *1 * 1* 1 A

= 5588A.

Conclusion : The calculated rating of the main busbar selected is more than the

desired rating.

Not e: For 4000A current rating the considered ambient temperature is 35°C & end temperature is 65°C, but

we consider 40°C as ambient temperature & end temperature as 115°C.Hence the busbar rating is less at 35°C

&more at 40T.

Chkd. By: VMG 0' Page 2 of 2.'{

Calculation Record

No.

Dept.:PTD - M /

PD

Prep. By :Pranoti

Client: MIS. RELIANCE PETROLEUM LTD.

Project: JAMNAGAR EXPORT REFINERY PROJECT

Consultant: BECHTEL FRANCE S.A.S

Sales Ref: -3000554079

3

t--_-+ +_--t---+-D-a-te-:-1-S.-Ol-.O-7--Iescription:- 6.6kV SwitchboardPrep:MG

ShNo.

Ckd: BBP~ Work :- 8BK80 - 3AB VCBr---+------+---r---+------~A As commented 23.01.07 BBP Siemens Ltd.I----+--~---+_--t--_,Issue Remarks Date Name PTD-MISOE Details:- RATING &SHORT

OFFIC,E CIRCIDT CALCULATION FOR

lVDDIUMVOLTAGEBECHTEL PROJECT SPEC. REF:25194 - 3PS - ES - 002

(4) - G71570 - U5227 - Z104

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SIEMENSLTD

PTD-M/PD

CALCULATION FOR CONDUCTORS CROSS-

SECTIONAL

PRODUCT8BK80-12kV

600-800WOW

Dept. Prep. Pranoti Chkd.VMG Index

AREA WITH REGARD TO THERMAL STRESSES DUE TO

CURRENTS OF SHORT DURATION

Client: - RIL-JERP.(W.O.No.3000554079)

Project JERP-JAMANGAR; 6.6kVMedium Voltage Switchboard

Consultant : MIs Bechtel S.A.S

Data Short Time Current (Din the r.m.s. value in amperes.

Duration (t) in Seconds.

Main Busbar Material

Main Busbar Cross Section

31S00A

1

Aluminium

3X160XlOmm

Reference Anriex BB oflEC 60298 ( Attached)

S =(I I a) * ,f (t 1 t : .0)

Where:

S is the cross section, in square millimeters

I isthe r.m.s. vallie of the current in amperes. .

a is expressed in (A/sq.mm),f (s/K) and has the following values:

13 for copper.

8. S for aluminium.

4.5 for iron.

2.S for lead

t is the time in seconds.

t:.0 is the temperature rise in (K) for bare conductors, it is normally 180K.

If the time is more than 2 s but less than S s , the value for t:.0 may be increased in same formula to 215K.

S =(31S00 1 S.S) * ,f( 1 1 ISO)

=276.22 sq.mm

Conclusion: The required cross sectionofMain Busbar is 276.22sq.mm & the provided cross section is 4800sq.mm for

31.SkA-1sec. Hence the Main busbar selected is suitable for use in the specified conditions.

PTD-MlPD 23/01/2007

Ckd: RBP ~ Work:- 8BK80 - 3AB VCB~--_'------------_'~~~r---_'----------~~A As commented 23.01.07 BBP Siemens Ltd.

Remarks Date Name PTD-M/SOEOFFICE

Issue

ShNo.

Client: MIS, RELIANCE PETROLEUM LTD.

Project: JAMNAGAR EXPORT REFINERY PROJECT

Consultant: BECHTEL FRANCE S.A,S

Sales Ref: -3000554079 .

~ ___' _' r-___,_D_a_t_e:_18_,_01_.0_7_ --IDescription:- 6.6kV Switchboard

Prep :MG

(4) - G71570 - U5227 - Z104 4

Details :- RATING & SHORT

CIRCIDT CALCULATION FOR

MIDIUM VOLTAGEBECHTEL PROJECT SPEC. REF:2S194 - 3PS - ES- 002

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SIEMENSLTD

PTD-M/PD

CALCULATION FOR CONDUCTORS CROSS-

SECTIONAL

PRODUCT

SBKSO-12kV

600-800WOW

Dept.

PTD-M/PDII

Prep. Pranoti

23/0112007

I Chkd.VMG }MexI ~ ..\~I":";';__--------1

AREA WITH REGARD TO THERMAL STRESSES DUE TO

CURRENTS OF SHORT DURATION

Client: - RIL-JERP. (W.O. no.3000554079)

Project : JERP -JAMANGAR; 6.6kV Medium Voltage Switchboard

Consultant : MIs Bechtel S.A.S

Data Short Time Current (I) ill the r.m.s. value in amperes.

Duration (t) in Seconds.

Earth Busbar Material

Earth Busbar Cross Section

31500A

1

Aluminium

IX50XIOmm

Reference .Annex BB afIEC 60298

S=

(IIa)

* > I (tl 1 1 0 )

Where:

S is the cross section, in square millimeters

Is the r.m.s. value of the current in amperes.

a is expressed in (A1sq.mm) > I (s /K) and has the following values:

13 for copper.

8.5 for aluminium.

4.5 for iron.

2.5 for lead

t is the time in seconds.

1 1 0 is the temperature rise in (K) for bare conductors, it is normally 180K.

lfthe time is more than 2 s but less than 5 s , the value for 1 1 0 may be increased in same formula to 215K.

S = ( 31500 / 8.5 ) * > I ( 1 1180)

= 276.22 sq.mm

Conclusion: The required cross sectionofthe Earth busbar is 276.22sq.mm & the provided cross section is 500sq.mm for

31.5kA-lsec. Hence the Earth busbar selected is suitable for use in the specified conditions.

Date

BBP

Sh No.

Client: MIS. RELIANCE PETROLEUM LTD.

Project: JAMNAGAR EXPORT REFINERY PROJECT

Consultant: BECHTEL FRANCE S.A.S

Sales Ref: -3000554079

1--_-+ -+-__ -+-__ +-D_a_te_:_1_S._O_1._O_7-I Description:- 6.6kV Switchboard

Prep: MG

Issue

As commented

Remarks

23.01.07

(4) - G71570 - U5227 - Zl04 5

Ckd: BBP ~ Work:- 8BK80 - 3AB VCBr---+------~--~--+-----~~

Siemens Lttl.PTD-M/SOE

OFFICE

A

Name Details :- RATING &SHORT

CmCUIT CALCULATION FOR

MIDIUM VOLTAGEBECHTEL .PROJECT SPEC. REF:25 194 - 3PS - ES 002

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IS 12729: ·2004

iec ·60694 (2002)

Table ' 3 : - Limits of temperature ana temperaturertse fer varlous parts, materlals and

dielectr.ics of high-voltage switchgear and controJgear

Maximum value

.Nature .of the part, of the material and of the dielectric Temperature Temperature rise at

(See points 1,2 and 3) (See note)ambient air temperature

not exceeding 40 'C

,·C K

"':~1 Contacts (see point 4)

..

Bare-copper or bare-copper alloy

- in air 75 35

- in SFs (sulphur hexafluoride) (see point 5) 105 65

- in oil B C i 40

SHver-coated or nickel-coated (see point 6)

- in air 105 65

- in SF6 (see' point 5) 105 ·65

- in oil 90 50

Tin-coated (see point 6)- in air 90 50

- in SF6 (see point 5) 90 50

- -In oil 90 50

2 Connection, bolted or the equivalent (see point 4)

Bare-copper, bare-copper alloy or bare-aluminium alloy

- in air 90 50

- in SFs (see point 5) 115 75

- in oil 1U O 60

Silver-coated or nickel-coated !lee point 6)

- in air 115 75

- in SF6 (see point 5) 115 75

- in oil 10 0 60

Tin-coated

in air 105 65

- in SF6 (see point 5) 105 65

- in oil 100 60

3 All other contacts·or connections made of bare metals

or coated with other materlals (see point 7) (see pcint 7)

4 Terminals for the connection to external conductors by

screws or bolts (see point 8)

- bare 90 50

- silver, nickel or tin-coated 105 65

- other coatings (see point 7) (see paint 7)

5 Oil for oil switching devices (see points 9 and 10) 90 50

6 Metal parts acting as springs. (see point 11) (see point 11)

7 Materials used as insulation and metal parts in contact

with insulation'of the following classes (see point 12}

- Y90 50

- A 105 .' 65

- E 120 80

- B 130 90

- F 155 115

- Enamel: oil base 100 60

synthetic 120 80

- H 180 140

- C other insulating material (see point 1.3) (see point 13)

8 Any part of metal or of lnsulatinq ma,';:;;·~:;:;~. .:;~.~~::::i .. .~. . .

,-~ uu

with oil, except contacts

9 Accessible parts

- expected to be touched in normal operation 70 30

- which need not to be touched in normal operation 80 40

NOTE The points referred to in this table are those of 4.4.3. ~

28

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, /

p~DIN 43 670 Seiie 3

= > 01..":IlJ)OOr-'_CID~= M e-~NO t.Oe,:)~ C)I:"':) t.l)Q ~~ -r--ae e= t-c Me=:.-:~ =:'- ..~ ~~ ~~. C" : ! . . C " " : I _ ~ . . ~f-_ 0.&1). ~Q_ M~~

ceQ =:00= c_ c- C-C":>~"" INc.::: Mr-_--_---------

llI

r>:< : s : .

\\v,,,~-'

' "= ,o S I •--I

~Ie - r :

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Liii i iJ:a:pU;

. '.

Q

DIN43670 s':;!7_.

Foktor k,

0.75 0.8 0.85 0.9 0.95 1

I I "1"""1'1,,,1"111''''11''''''''''1,,1.11'''11 "I rI""""I"".r' ' '·1'1"''I' ' ' ' ' I,I' ' ' I' ' I' ' ' ' I' ' ' ';,·I:!I,1""1"1"r ' , ', ' , ,' , '1',1f I.: Iiii II: Iiii II i\rrltlt\ ( t I l tn , tiil tp il " i fill Ii ')Pi·iiil jilt'i j ,hi Ii Ii Ii (:iii i tiil iI' i Ij111141'1 i i 1 1 ' 1 , 1 iii1111' Iii

20 1 l : m 2 25 30 .:?5/,

elektrische Leitftihigkeit bei 20°C -_-

e cd . b

aBild 1. Faktor k 1 fu r die Belastungsanderung bei Aluminium- Werkstoffen mit von 35,1 m/fl. mm2 abweichender

Leitfcihigkeit.

a: E-AI FS,5 bis F8; b: E-A I FlO ; c: E-AI F13; d : E -A lM g Si 0,5 F17; e: E-AlMgSi 0,5 F2 2

2 .2

2 .1

2 ,0

1 .9

1 ,8

1 ,7

1 ,6

1 .5

t 1 ,4

1 .3

J 1 . J . . 1 ' "! 1 _ .. f - " ' L

J 1 ! . . . . . I - - " !LI ! I -- ' f - " " 1 - - ' 1 ; . ,

1 i,

I I""

v I -- ' ' . . . . , - -I T L,..-

,. _..""

,;f

! 1 I 1 T . . . . . ,."fo'" v . . . . . lA""

, 1 j I I i / i . . - - A i . - ' " L,..- . . . . . V

I 1 IIY

l/'

,.". V

,. .

I vli:"- V : . . , . . . , fo'" L , . . - . . . . . 1 . . 0 ' 1 " ' " f . . -

1 C; / -, V t- ' "/ V 1 . , . 0 . . . . i'" I . - -

! '"7' I/. J . . " I - - ' / 1/ . . . . . . . . V l..;-

V V ~ V Y i " ' " I - - " / /1

k' " A· I - - ' / 1 L , . . - '/

" " ' "l..;- V ~

»: I V !/ V v - Y !AI' 1/ L , . . - V.V 1/ ". '/ V t> , i " ' " Y 1/ V v - I . . ; - I

V, / t> V , V i> 1/ I v - I - - "

V I: 1 / Iff V t> V t>

V I k1 1/ V t> V ., l/ Vy,y '1 V !/. V " 1/I l/ I ./ V ./ V, V

V ./ I....I....,

Vi LA I

/ ,/ r:I / 7 ,;/1 r;r IVi' ..... I . . . . . I V. Vi 1/

,

V 1/ / I.A I.....l/. i/

.~ 1.1 . . . . V! V I1/ \.I . . . . . '. , '/ : 1

. 1/ / . . . . v- I1 .1 I VI f i

~ ~ l7 1 7 1 7 , I I,I 1/ 7 7 T , 1

V 1/ / ! iL ./ I ! I ! I I I

7 V ! I , I !/ !/ I 7 I I I I I

IV II IT11 I

(. !/ / i I I I : I

3 I I' 1 1 I I 1 1 I I.

oD C

10

15 5

20 E

~~ ~:.QI'

35 ::,~40 :J,-

45 -'''''''' ....

50 \ ~~)

55

60

65

,~

1 )..'

a \2: xIf 1 .1

1 .0

0. 9

0, 8

0,7

0,6

0,5

O , L .

O. 50 55 60 65 70 75 80 85 90 95 100 105 110 115 D C 125

Schienentemperotur - ( j > _ . J ( \ c J , . ~ . I \ p )Bild 2. Faktor k2 filr die Belastungsanderung bel anderen Lufttemperaturen als 35°C und/oder anderen

Schienentemperaturen als 65 D C .

Tabelle S. Faktor k 3 filr die Belastungsminderung bel waagerechter Lage der Schienenbreite oder bei senkrechterSchienenfdhrung liinger-als 2 m.

. . ::.).- . . '

SchienenanzahlSchienenbreite Faktor k 3 bei Stromschienen

mm gestrichen blank

2 - 50 bis 200 0,85 0,8-50 bis 80 0,85 0,8

3 - 100 bis 120 0,8 0,75

- 160,

0,75-- ~ 0,74 -- i- 200 0,7 0,~5

2, . . . . . . . ,

bis 200 0,95 0,9L.......I

'.

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298 © t s c -81-

Annex BB

(normative)

Method of calculating the 'cross-sectional area of bare

conductors with regard to thermal stresses due .toeurrents

of short duration

The following formula can be used to calculate the cross-section ·of bare conductors necessary

to withstand the thermal' stress due to currents with a duration of the order of 0,2 s to 5 s.

S = . ! . . . ;-y-aV-s:Jf

)re:

S is the cross-section, expressed in square millimetres

Is the r .m. s , value of the current in amperes

. . A ( S ) Y .a IS expressed in 'mm' K and has the following values:

13 for copper8, 5 for aluminium4 ,5 for iron2, 5 for lead

t is the time, expressed in seconds

flO is the temperature rise, expressed in Kelvins (K); for bare conductors, it is normally 180 K,

If the time is more than 2 s but less than 5 s, the value for fl.() may be increased in the same

formula to 215 K.This takes account of the fact that the temperature rise is .not strictly adiabatic.