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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.
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