vd calculation
TRANSCRIPT
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SECTION-9
ELECTRICAL DESIGN CALCULATION
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 280 0.946 0.85 0.9 1 3 840 2 504
Total Load 840 504
3.0 = 752.15 kVA
4.0 = 0.8041
5.0
5.1 = 1250 kVA5.2 = 5 %
5.3 = 280 KW
5.4 = 3.3 kV
5.5 = 0.85
5.6 = 0.946
5.9 = 348.2153961 kVA
5.10 = 2089.292377 kVA
5.11 = 696.4307922 kVA
5.14 = 25000 kVA
(within 10%)S.C capacity of transformer
The selected rating of transformer is 1250 kVA
5.16Voltage drop at transformer terminal when largest
motor start with Star Delta starting= 4.2 %
[Motor Starting kVA (S/D) + Base Load kVA] x 100
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 9.750031091 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
S.C capacity of transformer
5.13 Fault current of transformer secondary side (ISC) = 4.373741456 kAFault Level in MVA
1.7321 x kV
5.12 Fault Level at transformer secondary side = 25 MVARating of transformer in MVA x 100
Impedance of transformer in %
Base load on transformer before starting Second
largest motor(Considering only one motor is working and the Second motor is starte
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
Motor starting Kva with Star Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 348.2153961 kVAkW
P.F x Efficiency
5.7 FLC of motor = 60.92016454 AkW x 1000
1.7321 x V x p.f x efficiency
Supply voltage System voltage
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest standard size (Confg. 33/3.3KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
Rating of the largest size motor From the above table
626.79
Considering 20% contingency
System P. F.
D. F.
Connected Load Working LoadWorking Load
(kVA)
Pump 626.79
Sr.
No.Item Description
Rating in
kWEffi. P. F. L. F.
= Motor EfficiencyInput Data and Calculations:
TRANSFORMER SIZING FOR CWPS PLANT
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
= Diversity Factor
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CAPACITOR BANK SIZING ACROSS MOTOR TERMINAL
1 Motor rating (kW) 280
2 Motor rating after 90% load factor (kW) 252 To be considered for further calculations
3 Supply Voltage (V) 3300
4 Motor Power Factor (p.f 1) 0.85 Based on actual Values given by jyoti
5 Motor efficiency (Effi.) 0.946 Based on actual Values given by jyoti
6 Power Factor to be improved (p.f 2) 0.98
7 No load p.f. (p.f NL) 0.1 Assumption
8 Motor Full Load Current in amp.(FLC) 54.828 = (kW x 1000) / (1.7321 x V x cos(p.f 1) x Effi.)
9 No load current in amp. (INLC) 19.190 35% of FLC
10 Motor magnetising current in amp. 19.094 = [ INLC x sin(cos-1
p.f NL) ]
11 Capacitor current (Ic) 17.184 Shall be 90% of motor magnetising current
12Max. kVAR that can be connected across motor
terminal98.22 = (1.7321 x V x Ic) / 1000
13Total kVAR to be connected across the motor
terminal105.00 = kW[ tan(cos
-1p.f 1) - tan(cos
-1p.f 2) ]
14Excess kVAR to be connected across the
switchgear bus bars (13 - 12)6.79
Negative value indicates capacitor bank is not
required across the bus.
Main Pumps For Clear water pumping station
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.2.0
UnitTotal
(kW)Unit
Total
(kW)
a EOT crane 15 0.87 0.82 1 2 1 15 1 7.5
b Exhaust fan 0.5 0.67 0.82 1 1 8 4 8 4
c 15 0.8 0.8 1 1.5 Lumpsum 15 Lumpsum 10
d 1.5 0.79 0.81 0.9 1 2 3 2 2.7
e 7.5 0.87 0.82 0.9 1 2 15 2 13.5
f 160 0.962 0.86 0.9 2 2 320 1 72
g 37 0.935 0.86 0.9 2 2 74 1 16.65
h 1.1 0.79 0.81 0.9 2 2 2.2 1 0.495
i 1.1 0.77 0.81 0.9 1 2 2.2 1 0.99
j 3.7 0.77 0.82 0.9 1 2 7.4 1 3.33
k 1.5 0.79 0.81 1 2 3 4.5 3 2.25
l 1.5 0.79 0.81 1 2 3 4.5 3 2.25
m 1.5 0.79 0.81 1 2 3 4.5 3 2.25
n 1.5 0.79 0.81 1 1 2 3 1 1.5
o 1.5 0.79 0.81 1 1 2 3 1 1.5
p 1.5 0.79 0.81 1 1 2 3 1 1.5
q 0.5 0.67 0.82 0.9 2 30 15 30 6.75
r 7.5 0.87 0.82 0.9 1 1 7.5 1 6.75
s 40 0.902 0.81 1 1.5 Lumpsum 40 Lumpsum 26.666667
Total Load 542.8 182.58167
3.0 = 297.31 kVA
4.0 = 0.7369
5.0
5.1 = 315 kVA
5.2 = 4.5 %
5.3 = 160 KW
5.4 = 0.415 kV
5.5 = 0.86
5.6 = 0.962
5.9 = 121.6044578 kVA
5.10 = 1160.373253 kVA
5.11 = 386.7910845 kVA
5.14 = 7000 kVA
= Motor EfficiencyInput Data and Calculations:
D. F.
Connected Load Working LoadWorking Load
(kVA)
TRANSFORMER SIZING FOR CWPS PLANT
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
= Diversity Factor
Sr.
No.Item Description
Rating in
kWEffi. P. F. L. F.
247.76
Considering 20% contingency
10.51
7.28
Flash mixture 4.22
Lighting (CWPS) 15.63
System P. F.
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 33/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
Rating of the largest size motor From the above table
Supply voltage System voltage
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 269.0452946 AkW x 1000
1.7321 x V x p.f x efficiency
5.8 Rating of largest size motor in kVA = 193.3955422 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
Motor starting Kva with Star Delta start = 3 x 1.7321 x kV x I FLC
5.12 Fault Level at transformer secondary side = 7 MVARating of transformer in MVA x 100
Impedance of transformer in %
5.13 Fault current of transformer secondary side (ISC) = 9.738161699 kAFault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 18.3139673 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
S.C capacity of transformer
(within 10%)S.C capacity of transformer
The selected rating of transformer is 400 kVA
5.16Voltage drop at transformer terminal when largest
motor start with Star Delta starting= 7.3 %
[Motor Starting kVA (S/D) + Base Load kVA] x 100
Clarifloculator mechanism phase-1 18.92
backwash pumps 87.03
Air blower 20.71
Chlorine booster pumps for prechlorination 0.77
Chlorine booster pumps for postchlorination 1.59
Service water pumps 5.27
Agitator for Alum dosing pump 3.52
Agitaotor for Lime dosing pump 3.52
Agitator for polyelectrolyte dosing tank 3.52
Dosing pump for alum 2.34
Dosing pump for lime 2.34
Dosing pump for polyelectrolyte 2.34
EOT crane 9.46
Lighting (chemical,Filter,pump,outdoor) 36.50
Valves 12.29
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CAPACITOR BANK SIZING ACROSS BUS
Intermediate Pumping Station
1 Average Power factor (pf1) 0.737
2 Total Working load in IPS 210 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 150 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
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Short circuit calculation CWPS main Pump
Assumptions
1 Fault level at 220kV bus 20000 MVA (as per IS :2026)
2 Base MVA 2000
Ratio = 220kV / 132kV
Capacity = 100.00 MVA
Z= 9.27%
Qty 1 Nos
Considering negative tolerance Z = 8.34%
Net Z for transformers single transformer= 8.34%
3
Ratio = 132kV / 33kV
Capacity = 40.00 MVA
Z= 10.18%
Qty 1 Nos
Considering negative tolerance Z = 9.16%
Net Z for transformers single transformer= 9.16%
4
Line length = 15 kM
Conductor Type = DOG Assumed
Conductor Resiatance = 0.2733 ohm/kM
Z,Considering Reactance Negligible = 4.0995 ohm
5
Ratio = 33kV / 3.3kV
Capacity = 1.25 MVA
Z= 5.0%
Qty 1 Nos
Considering negative tolerance Z = 4.5%
Net Z for transformers single transformer= 4.5%
6 K' Constant for XLPE AL cable= 94
K' Constant for PVC AL cable= 75
K' Constant for PVC CU cable= 112
7 Fault clearing time for 33kV Breaker (t) = 1 Sec
Fault clearing time for 3.3kV Breaker (t) = 1 Sec
10 Starting Voltage dip = 15%
11 Starting current for DOL= 6 times
12 Starting current for Y-D= 2 times
13 Starting current for FCMA softstarter= 2.5 times
Transformer Details at Chandaka220KV/132KV
Transformer Details at Chandaka 132KV/33KV
33kV Over head line from Chandaka to CWPS
Transformer at CWPS
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Calculation
a chandaka Grid Substation
220KV Bus 0.1 20000 52
220KV/132KV,100MVA transformer 1.7
1 132kV Bus 1.8 1130.8 5
2 132kV/33kV,40MVA transformer 4.6
3 33kV Bus 6.3 315.0 5.51 58.6
b CWPS
1 15 kM 33kV O/H line from Chandaka Substation to CWPS 7.53
2 33kV Bus 13.88 144.1 2.52 26.8
3
33kV , XLPE, cable 3core x 95sqmm cable from 6 Pole
structure to 33KV panel 0.03950
4 33kV panel 13.92 143.7 2.51 26.7
5
33kV , XLPE, cable 3core x 95sqmm cable from 33KV panel
to transformer 0.000987
6 33kV/3.3kV, 1.25MVA transformer 72.00
7 3.3kV side of 1.25MVA transformer 86.02 23.3 4.07 43.3
(XLPE,AL,3.3 kV)
8
3.3kV , XLPE, cable 3core x 300sqmm cable from
transformer secondary to CWPS PMCC 1.91
9 3.3kV CWPS PMCC Bus 87.83 22.8 3.98 42.4
(,AL,3.3 kV)
Sr No Description
Impedance "
Z"
Fault level
"MVA"
Fault Current
"kA"
Minimum Cable
size "SQMM"
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 349
2 VOLTAGE (V) = 3.3
3 PF = 0.84 FAULT CURRENT Ish = 3.98
5 FAULT CLEARING TIME t = 1
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 42.34042553
2 CABLE SIZE CHOSEN = 50 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.76
3 OVERALL DERATING FACTOR = 0.722
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 35.25
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
48.83
3 Current carring capacity of 3.5C x50 Sqmm AL XLPE cable is = 120
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x50 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 50 SQmm AL XLPE Cable) = 0.82
3 X AT CONDUCTOR TEMP. (3C x 50 Qmm AL XLPE Cable) = 0.086
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.052371797
CABLE SIZE CHOSEN = 3.5CX50 sq.mm Al XLPE Cable
#$#%&"'(")*+"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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Short circuit calculation CWPS Auxilary WTP load
Assumptions
1 Fault level at 220kV bus 20000 MVA (as per IS :2026)
2 Base MVA 2000
Ratio = 220kV / 132kV
Capacity = 100.00 MVA
Z= 9.27%
Qty 1 Nos
Considering negative tolerance Z = 8.34%
Net Z for transformers single transformer= 8.34%
3
Ratio = 132kV / 33kV
Capacity = 40.00 MVA
Z= 10.18%
Qty 1 Nos
Considering negative tolerance Z = 9.16%
Net Z for transformers single transformer= 9.16%
4
Line length = 15 kM
Conductor Type = DOG Assumed
Conductor Resiatance = 0.2733 ohm/kM
Z,Considering Reactance Negligible = 4.0995 ohm
5
Ratio = 33kV / 0.415kV
Capacity = 0.32 MVA
Z= 4.5%
Qty 1 Nos
Considering negative tolerance Z = 4.1%
Net Z for transformers single transformer= 4.1%
6 K' Constant for XLPE AL cable= 94
K' Constant for PVC AL cable= 75
K' Constant for PVC CU cable= 112
7 Fault clearing time for 33kV Breaker (t) = 1 Sec
Fault clearing time for 0.415kV ACB Breaker (t) = 0.08 Sec
Fault clearing t ime for 0.415kV MCCB Breaker (t) = 0.04 Sec
10 Starting Voltage dip = 15%
11 Starting current for DOL= 6 times
12 Starting current for Y-D= 3.5 times
13 Starting current for FCMA softstarter= 2.5 times
Formula used
1
2
3 Zline =
4 Zcable =
Transformer Details at Chandaka220KV/132KV
Transformer Details at Chandaka 132KV/33KV
33kV Over head line from Chandaka to CWPS
Transformer at CWPS
Zsource =Base MVA
Fault level at 132kV bus
Ztransformer =Base MVA
X tranformer Z%Transformer capacity in MVA
Base MVAX Line Z
kV2
Base MVAX Cable Z
kV2
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Calculation
a chandaka Grid Substation
1 220KV Bus 0.1 20000 52
2 220KV/132KV,100MVA transformer 1.7
3 132kV Bus 1.8 1130.8 5
4 132kV/33kV,40MVA transformer 4.6
5 33kV Bus 6.3 315.0 5.51
b CWPS
1 15 kM 33kV O/H line from Chandaka Substation to CWPS 7.53
2 33kV Bus 13.88 144.1 2.52 26.8
4 33kV/0.415kV, 315KVA transformer 257.14
5 0.415kV side of 315KVA transformer 271.02 7.4 10.27 30.9
(XLPE,AL,0.415kV)
6
0.415kV , XLPE, cable 2 X 3.5c x 240.sqmm cable from
transformer secondary to CWPS PMCC 40.66
7 0.415kV CWPS AUXILARY MCC 311.68 6.4 8.93 26.9
(,AL,0.415 kV)
8
0.415kV , XLPE, cable 2 x 3.5core x 120sqmm cable from
CWPS PMCC to Motor (160KW) 81.31
9 0.415kV 160KW motor (194) 392.99 5.1 7.08 15.1
(,AL,0.415 kV)
10
0.415kV , XLPE, cable 3.5C x 240sqmm cable from CWPS
PMCC to WTP & Chemical 508.19
11 0.415kV WTP & Chemical 819.87 2.4 3.39 7.2
(,AL,0.415 kV)
Sr No Description
Impedance "
Z"
Fault level
"MVA"
Fault Current
"kA"
Minimum Cable
size "SQMM"
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 315
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 10.275 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 30.90207082
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable directly burried (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 438.24
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
668.56
3 Current carring capacity of 3.5C x240 Sqmm AL XLPE cable is = 326
4 No of cable required = 2.05
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x240 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 240 SQmm AL XLPE Cable) = 0.16
3 X AT CONDUCTOR TEMP. (3.5C x 240 Qmm AL XLPE Cable) = 0.071
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 2
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.624055741
CABLE SIZE CHOSEN = 2X3.5CX240 sq.mm Al XLPE Cable
""*,-+
(FULL LOAD CURRENT X LENGTH X IMPEDENCE)/NO
OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 194
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 8.935 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 19
2 CABLE SIZE CHOSEN = 25 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 155.83
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
248.54
3 Current carring capacity of 3C x120 Sqmm AL XLPE cable is = 257
4 No of cable required = 0.97
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 120SQmm AL XLPE Cable = 0.324
3 X AT CONDUCTOR TEMP. (3C x 120 Qmm AL XLPE Cable) = 0.0712
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.785433685
CABLE SIZE CHOSEN = 2X3CX120 sq.mm Al XLPE Cable
*,-+".*"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 46
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 8.935 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 19
2 CABLE SIZE CHOSEN = 25 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 36.95
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
58.93
3 Current carring capacity of 3C x25 Sqmm AL XLPE cable is = 96
4 No of cable required = 0.61
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x25 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 25SQmm AL XLPE Cable) = 1.54
3 X AT CONDUCTOR TEMP. (3C x 25 Qmm AL XLPE Cable) = 0.0805
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.789742459
CABLE SIZE CHOSEN = 2X3CX25 sq.mm Al XLPE Cable
*,-+"#/*"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 91
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 8.935 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 250
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 19
2 CABLE SIZE CHOSEN = 25 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable directly burried (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 126.60
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
193.14
3 Current carring capacity of 3.5C x240 Sqmm AL XLPE cable is = 367
4 No of cable required = 0.53
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x240 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 300 SQmm AL XLPE Cable) = 0.128
3 X AT CONDUCTOR TEMP. (3.5C x 300Qmm AL XLPE Cable) = 0.0705
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.911409493
CABLE SIZE CHOSEN = 3.5CX300 sq.mm Al XLPE Cable
+*,-+"*,+
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 20
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.395 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 120
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.212765957
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable directly burried (6 cables touching)
RATING FACTOR = 0.54
3 OVERALL DERATING FACTOR = 0.513
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 27.82
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
54.24
3 Current carring capacity of 3.5C x35 Sqmm AL XLPE cable is = 113
4 No of cable required = 0.48
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x35 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 35 SQmm AL XLPE Cable) = 1.11
3 X AT CONDUCTOR TEMP. (3.5C x 35 Qmm AL XLPE Cable) = 0.0783
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.302918856
CABLE SIZE CHOSEN = 3.5CX35 sq.mm Al XLPE Cable
*,'&0+",1
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
522
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A) FEEDER DATA
1 WORKING LOAD (KW) 5.6
2 WORKING LOAD (KVA) = 7
2 VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 3.39
5 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 120
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.212765957
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable directly burried (6 cables touching)
RATING FACTOR = 0.54
3 OVERALL DERATING FACTOR = 0.513
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 9.74
2 CURRENT RATING REQ.AFTER CONSIDERING DERA = FULL LOAD CURRENT/DERATING FACTOR
18.98
3 Current carring capacity of 4C x16 Sqmm AL XLPE cable = 67
4 No of cable required = 0.28
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x16 SQmm AL XLPE C = 2.44
3 X AT CONDUCTOR TEMP. (4C x16 Qmm AL XLPE Cab = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.976550907
CABLE SIZE CHOSEN = 4CX16 sq.mm Al XLPE Cable
*,'&0+",1
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
523
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A) FEEDER DATA
1 WORKING LOAD (KW) 12
2 WORKING LOAD (KVA) = 15
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.39
5 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 105
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.212765957
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable directly burried (6 cables touching)
RATING FACTOR = 0.54
3 OVERALL DERATING FACTOR = 0.513
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 20.87
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
40.68
3 Current carring capacity of 4C x16 Sqmm AL XLPE cable is = 67
4 No of cable required = 0.61
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x16 SQmm AL XLPE Cable) = 2.443 X AT CONDUCTOR TEMP. (4C x16 Qmm AL XLPE Cable) = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.831032951
CABLE SIZE CHOSEN = 4CX16 sq.mm Al XLPE Cable
*,'&0+",1#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
524
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 75
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 8.935 FAULT CLEARING TIME t = 0.04
6 CONSTANT K = 94
7 LENGTH = 25
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 19
2 CABLE SIZE CHOSEN = 25 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 104.34
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
166.42
Considering 35% extra current 224.66
3 Current carring capacity of 3.5C x120 Sqmm AL XLPE cable is = 257
4 No of cable required = 0.87
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQmm AL XLPE Cable) = 0.264
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qmm AL XLPE Cable) = 0.0716
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.276701989
CABLE SIZE CHOSEN = 3.5CX120 sq.mm Al XLPE Cable
*,23&0!+"/4&"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
525
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 100
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 25
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 139.12
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
212.24
3 Current carring capacity of 3.5C x120 Sqmm = 223
4 No of cable required = 0.95
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQ = 0.324
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qm = 0.0712
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.438263899
CABLE SIZE CHOSEN = 3.5CX120 sq.mm Al XLPE Cable
!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
526
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 29
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 45
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.952 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 40.35
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
64.35
3 Current carring capacity of 3C x16 Sqmm AL = 70
4 No of cable required = 0.92
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm = 2.44
3 X AT CONDUCTOR TEMP. (3C x 16 Qmm = 0.0808
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.515823138
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
$!"#%%&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
527
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 16
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 55
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 22.26
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
35.50
3 Current carring capacity of 3C x10 Sqmm AL = 67
4 No of cable required = 0.53
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (3C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.636204732
CABLE SIZE CHOSEN = 2X3CX10 sq.mm Al XLPE Cable
$!"#&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
528
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 20
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 35
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 27.82
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
44.38
Considering 35% extra current 59.91
3 Current carring capacity of 4C x10 Sqmm AL = 67
4 No of cable required = 0.89
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.301526492
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
$!"#%'
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
529
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A) FEEDER DATA
1 WORKING LOAD (KW) 10
2 WORKING LOAD (KVA) = 12.5
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 17.39
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
27.74
3 Current carring capacity of 4C x10 Sqmm AL = 67
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.697246335
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
$!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
530
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 22 0.917 0.83 0.9 1 2 44 1 19.8
2.2 11 0.892 0.81 0.9 1 2 22 2 19.8
2.3 2 0.83 0.82 1 2 1 2 1 1
2.4 0.5 0.67 0.82 1 1 6 3 6 3
2.5 10 0.8 0.8 1 1.5 Lumpsum 10 Lumpsum 6.6666667
81 50.266667
3.0 = 84.92 kVA
4.0 = 0.71
5.0
5.1 = 100 kVA
5.2 = 4.5 %
5.3 = 22 KW5.4 = 0.415 kV
5.5 = 0.83
5.6 = 0.917
5.9 = 71.095 kVA
5.10 = 173.43 kVA
5.11 = 101.17 kVA
5.14 = 2222.2 kVA
TRANSFORMER SIZING FOR JATNI (KAJU PLANTATION) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Lighting 10.42
5.46
1.47
Sr.
No.L. F. D. F.
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
Rating of the largest size motor From the above table
Considering 20% contingency
System P. F.
= Diversity Factor
= Motor Efficiency
Item DescriptionRating in
kWEffi.
Working Load
(kVA)
Connected Load Working Load
Input Data and Calculations:
P. F.
Total Load
Chain pully
Exhaust Fan
70.77
Pump-1 26.01
Pump-2 27.40
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 40.212 AkW x 1000
1.7321 x V x p.f x efficiency
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 28.905 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 3.0915
5.12 Fault Level at transformer secondary side = 2.2222
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 11.004 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
The selected rating of transformer is 100 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 7.8
531
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.710
2 Total Working load 50 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 40 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
532
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 22 0.917 0.83 0.9 1 2 44 1 19.8
2.2 11 0.892 0.81 0.9 1 2 22 2 19.8
2.3 2 0.83 0.82 1 2 1 2 1 1
2.4 0.5 0.67 0.82 1 1 6 3 6 3
2.5 10 0.8 0.8 1 1.5 Lumpsum 10 Lumpsum 6.6666667
81 50.266667
3.0 = 84.92 kVA
4.0 = 0.71
5.0
5.1 = 100 kVA
5.2 = 4.5 %
5.3 = 22 KW5.4 = 0.415 kV
5.5 = 0.83
5.6 = 0.917
5.9 = 71.095 kVA
5.10 = 173.43 kVA
5.11 = 101.17 kVA
5.14 = 2222.2 kVA
TRANSFORMER SIZING FOR JATNI (KAJU PLANTATION) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Lighting 10.42
5.46
1.47
Sr.
No.L. F. D. F.
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
Rating of the largest size motor From the above table
Considering 20% contingency
System P. F.
= Diversity Factor
= Motor Efficiency
Item DescriptionRating in
kWEffi.
Working Load
(kVA)
Connected Load Working Load
Input Data and Calculations:
P. F.
Total Load
Chain pully
Exhaust Fan
70.77
Pump-1 26.01
Pump-2 27.40
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 40.212 AkW x 1000
1.7321 x V x p.f x efficiency
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 28.905 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 3.0915
5.12 Fault Level at transformer secondary side = 2.2222
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 11.004 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
The selected rating of transformer is 100 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 7.8
533
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.710
2 Total Working load 50 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 40 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
534
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 100
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 25
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 139.12
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
212.24
3 Current carring capacity of 3.5C x120 Sqmm = 223
4 No of cable required = 0.95
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQ = 0.324
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qm = 0.0712
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.438263899
CABLE SIZE CHOSEN = 3.5CX120 sq.mm Al XLPE Cable
!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
535
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 29
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 45
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.952 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 40.35
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
64.35
3 Current carring capacity of 3C x16 Sqmm AL = 70
4 No of cable required = 0.92
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm = 2.44
3 X AT CONDUCTOR TEMP. (3C x 16 Qmm = 0.0808
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.515823138
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
$!"#%%&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
536
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 16
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 55
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 22.26
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
35.50
3 Current carring capacity of 3C x10 Sqmm AL = 67
4 No of cable required = 0.53
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (3C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.636204732
CABLE SIZE CHOSEN = 2X3CX10 sq.mm Al XLPE Cable
$!"#&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
537
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 20
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 35
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 27.82
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
44.38
Considering 35% extra current 59.91
3 Current carring capacity of 4C x10 Sqmm AL = 67
4 No of cable required = 0.89
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.301526492
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
$!"#%'
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
538
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A) FEEDER DATA
1 WORKING LOAD (KW) 10
2 WORKING LOAD (KVA) = 12.5
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 2.64
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 7.943667669
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 17.39
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
27.74
3 Current carring capacity of 4C x10 Sqmm AL = 67
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQm = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.697246335
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
$!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
539
7/30/2019 vd calculation
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 45 0.936 0.86 0.9 1 2 90 1 40.5
2.2 2.5 0.83 0.82 1 1 1 2.5 1 2.5
2.3 8 0.8 0.8 1 1.3 Lumpsum 8 Lumpsum 6.1538462
2.4 0.5 0.67 0.82 1 1 6 3 6 3
103.5 52.153846
3.0 = 82.87 kVA
4.0 = 0.76
5.0
5.1 = 100 kVA
5.2 = 4.5 %
5.3 = 45 KW
5.4 = 0.415 kV
5.5 = 0.86
5.6 = 0.936
5.9 = 44.097 kVA
5.10 = 335.42 kVA
5.11 = 111.81 kVA
5.14 = 2222.2 kVA
The selected rating of transformer is 100 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 7.0
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting=
17.078%
[Motor Starting kVA (DOL) + Base Load kVA] x 100
(within 10%)
2.2222
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 3.0915
5.12 Fault Level at transformer secondary side =
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 55.903 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor
5.7 FLC of motor = 77.771 AkW x 1000
1.7321 x V x p.f x efficiency
Rating of the largest size motor From the above table
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
9.62
Pump (existing)
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
System P. F.
= Diversity Factor
= Motor Efficiency
Item Description Rating inkW
Effi. Working Load(kVA)
Connected Load Working Load
Input Data and Calculations:
D. F.
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
P. F.
Considering 20% contingency
Total Load 69.06
Lighting
TRANSFORMER SIZING FOR JATNI (PHED Transmission) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
5.46Exhaust Fan (existing)
3.67Chain pully (existing)
50.31
Sr.No.
L. F.
540
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.755
2 Total Working load 52 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 35 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
541
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 100
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 60
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 139.12
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
212.24
3 Current carring capacity of 3.5C x120 Sqmm AL XLPE cable is = 223
4 No of cable required = 0.95
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQmm AL XLPE Cable) = 0.324
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qmm AL XLPE Cable) = 0.0712
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.051833358
CABLE SIZE CHOSEN = 3.5CX120 sq.mm Al XLPE Cable
!"#$
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
542
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 56
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.095 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 77.91
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
124.26
3 Current carring capacity of 3C x50 Sqmm AL XLPE cable is = 142
4 No of cable required = 0.88
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x50 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 50 SQmm AL XLPE Cable) = 0.82
3 X AT CONDUCTOR TEMP. (3C x 50 Qmm AL XLPE Cable) = 0.075
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.911737553
CABLE SIZE CHOSEN = 2X3CX50 sq.mm Al XLPE Cable
!"#$%&'
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
543
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 20
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.095 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 27.82
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
44.38
Considering 35% extra current 59.91
3 Current carring capacity of 4C x10 Sqmm AL XLPE cable is = 67
4 No of cable required = 0.89
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQmm AL XLPE Cable) = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm AL XLPE Cable) = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.487458847
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
!"#$(!)!
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
544
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A) FEEDER DATA
1 WORKING LOAD (KW) 15
2 WORKING LOAD (KVA) = 18.75
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 3.095 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 26.09
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
41.60
3 Current carring capacity of 4C x10 Sqmm AL XLPE cable is = 67
4 No of cable required = 0.62
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQmm AL XLPE Cable) = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm AL XLPE Cable) = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.394492669
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
!"#$
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
545
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.749
2 Total Working load 81 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 55 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
546
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 37 0.935 0.86 0.9 1 2 74 1 33.3
2.2 18.5 0.913 0.83 0.9 1 2 37 2 33.3
2.3 2.5 0.87 0.82 1 1 1 2.5 1 2.5
2.4 0.5 0.67 0.82 1 1 6 3 6 3
2.5 10.124 0.8 0.8 1 1.2 Lumpsum 10.124 Lumpsum 8.4366667
126.624 80.536667
3.0 = 129.00 kVA
4.0 = 0.75
5.0
5.1 = 160 kVA
5.2 = 4.5 %
5.3 = 37 KW
5.4 = 0.415 kV
5.5 = 0.86
5.6 = 0.935
5.9 = 113.99 kVA
5.10 = 276.09 kVA
5.11 = 161.05 kVA
5.14 = 3555.6 kVA
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
P. F.
= Diversity Factor
= Motor Efficiency
TRANSFORMER SIZING FOR JATNI (PHED) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Working Load(kVA)
Connected Load
System P. F.
5.46
3.50
Pump-1 41.41
Sr.No.
L. F. D. F.
Lighting 13.18
Working Load
Considering 20% contingency
Input Data and Calculations:
Total Load
Crane
Exhaust Fan
107.50
Pump-2 43.94
Item Description Rating inkW
Effi.
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
Rating of the largest size motor From the above table
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 64.013 AkW x 1000
1.7321 x V x p.f x efficiency
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 46.014 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 4.9464
5.12 Fault Level at transformer secondary side = 3.5556
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largestmotor start with DOL starting
= 10.971 %[Motor Starting kVA (DOL) + Base Load kVA] x 100
(within 10%)
The selected rating of transformer is 160 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 7.7
547
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 160
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.955 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 222.60
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
339.59
3 Current carring capacity of 3.5C x120 Sqmm AL XLPE cable is = 223
4 No of cable required = 1.52
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQmm AL XLPE Cable) = 0.324
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qmm AL XLPE Cable) = 0.0712
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 2
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.420733343
CABLE SIZE CHOSEN = 2X3.5CX120 sq.mm Al XLPE Cable
!"#$%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
548
7/30/2019 vd calculation
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 46
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.95
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 55
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 64.00
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
102.07
3 Current carring capacity of 3C x35 Sqmm AL XLPE cable is = 117
4 No of cable required = 0.87
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x35 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 35 SQmm AL XLPE Cable) = 1.113 X AT CONDUCTOR TEMP. (3C x 35 Qmm AL XLPE Cable) = 0.0783
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.373493628
CABLE SIZE CHOSEN = 2X3CX35 sq.mm Al XLPE Cable
!"#$%&'(
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
549
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 25
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.95
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 65
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 34.78
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
55.47
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is = 70
4 No of cable required = 0.79
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm AL XLPE Cable) = 2.443 X AT CONDUCTOR TEMP. (3C x 16 Qmm AL XLPE Cable) = 0.0783
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.886103934
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
!"#$%)*+(
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
550
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 30
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.955 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 41.74
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
66.57
Considering 35% extra current 89.87
3 Current carring capacity of 3.5C x25 Sqmm AL XLPE cable is = 96
4 No of cable required = 0.94
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x25 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 25 SQmm AL XLPE Cable) = 1.54
3 X AT CONDUCTOR TEMP. (3.5C x 25 Qmm AL XLPE Cable) = 0.0805
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.892065612
CABLE SIZE CHOSEN = 3.5CX25 sq.mm Al XLPE Cable
!"#$%,'"-"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW) 10
2 WORKING LOAD (KVA) = 12.5
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.955 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 17.39
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
27.74
3 Current carring capacity of 4C x16 Sqmm AL XLPE cable is = 67
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 16 SQmm AL XLPE Cable) = 2.44
3 X AT CONDUCTOR TEMP. (4C x 16 Qmm AL XLPE Cable) = 0.0808
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.580775149
CABLE SIZE CHOSEN = 4CX16 sq.mm Al XLPE Cable
!"#$%
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 160
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.945 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 35
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.86428723
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 222.60
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
339.59
3 Current carring capacity of 3.5C x120 Sqmm AL XLPE cable is = 223
4 No of cable required = 1.52
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQmm AL XLPE Cable) = 0.324
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qmm AL XLPE Cable) = 0.0712
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 2
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.490855567
CABLE SIZE CHOSEN = 2 X 3.5CX120 sq.mm Al XLPE Cable
!"#$%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 37
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.955 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 60
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 29.72
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
47.40
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is = 70
4 No of cable required = 0.68
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm AL XLPE Cable) = 2.44
3 X AT CONDUCTOR TEMP. (3C x 16 Qmm AL XLPE Cable) = 0.0808
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.48882313
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
!"#$%&'
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 24
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.95
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 70
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 33.39
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
53.25
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is = 70
4 No of cable required = 0.76
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm AL XLPE Cable) = 2.443 X AT CONDUCTOR TEMP. (3C x 16 Qmm AL XLPE Cable) = 0.0783
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.949941298
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
!"#$%()*'
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 13
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.95
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 85
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 18.09
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
28.85
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is = 70
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 16 SQmm AL XLPE Cable) = 2.443 X AT CONDUCTOR TEMP. (3C x 16 Qmm AL XLPE Cable) = 0.0783
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.282550675
CABLE SIZE CHOSEN = 2X3CX16 sq.mm Al XLPE Cable
!"#$%+)&'
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW) 15
2 WORKING LOAD (KVA) = 18.75
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 4.955 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 26.09
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
41.60
3 Current carring capacity of 4C x16 Sqmm AL XLPE cable is = 70
4 No of cable required = 0.59
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x16 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 16 SQmm AL XLPE Cable) = 2.44
3 X AT CONDUCTOR TEMP. (4C x 16 Qmm AL XLPE Cable) = 0.0808
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.653372042
CABLE SIZE CHOSEN = 4CX16 sq.mm Al XLPE Cable
!"#$%,#,
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 31
2 VOLTAGE (V) = 0.415
3PF = 0.84 FAULT CURRENT Ish = 4.95
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 14.89437688
2 CABLE SIZE CHOSEN = 16 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 43.13
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
68.79
Considering 35% extra current 92.86
3 Current carring capacity of 3.5C x25 Sqmm AL XLPE cable is = 96
4 No of cable required = 0.97
E) CHECK FOR VOLTAGE DROP1 CABLE SIZE = 3.5C x25 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 25 SQmm AL XLPE Cable) = 3.94
3 X AT CONDUCTOR TEMP. (3.5C x 25 Qmm AL XLPE Cable) = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 2.305561214
CABLE SIZE CHOSEN = 3.5CX25 sq.mm Al XLPE Cable
.
!"#$%&"-"
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 18.5 0.913 0.83 0.95 1 2 37 1 17.575
2.2 9.3 0.892 0.81 0.95 1 2 18.6 2 17.67
2.3 30 0.925 0.84 0.95 1 2 60 1 28.5
2.4 0.5 0.67 0.82 1 1 8 4 8 4
2.4 7.5 0.87 0.82 1 2 1 7.5 1 3.75
2.5 11.314 0.8 0.8 1 1.5 Lumpsum 11.314 Lumpsum 7.5426667
138.414 79.037667
3.0 = 130.38 kVA
4.0 = 0.73
5.05.1 = 160 kVA
5.2 = 4.5 %
5.3 = 30 KW
5.4 = 0.415 kV
5.5 = 0.84
5.6 = 0.925
5.9 = 121.39 kVA
5.10 = 231.66 kVA
5.11 = 77.22 kVA
5.14 = 3555.6 kVA
The selected rating of transformer is 160 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 5.6
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 9.9295 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
3.5556
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %kA
Fault Level in MVA
1.7321 x kV
(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 4.9464
5.12 Fault Level at transformer secondary side =
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 38.61 kVAkW
P.F x Efficiency
Base load on transformer before starting fourth
largest motor
5.7 FLC of motor = 53.713 AkW x 1000
1.7321 x V x p.f x efficiency
Supply voltage System voltage
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
Pump-3
Total Load
Exhaust Fan
Lighting and small power (indoor and outdoor) 11.79
108.65
36.68
7.28
Calculation to check the starting of largest size motorRating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
Pump -1 23.19
Pump-2 24.46
Rating of the largest size motor From the above table
Considering 20% contingency
System P. F.
TRANSFORMER SIZING FOR KHORDA (JAMADEI) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Crane 5.26
= Diversity Factor
= Motor Efficiency
Sr.
No.Item Description
Rating in
kW
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
Effi.Working Load
(kVA)
Input Data and Calculations:
P. F. L. F. D. F.Connected Load Working Load
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.727
2 Total Working load 79 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 59 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 22 0.917 0.83 0.95 1 2 44 1 20.9Pump -1 27.46
= Diversity Factor
= Motor Efficiency
Item DescriptionRating in
kWEffi.
Working Load
(kVA)
Input Data and Calculations:
P. F. L. F. D. F.Connected Load Working Load
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
TRANSFORMER SIZING FOR KHORDA ( Gurjanga) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Sr.
No.
-. . .
2.3 7.5 0.87 0.82 0.9 2 1 7.5 1 3.375
2.4 0.5 0.67 0.82 1 1 8 4 8 4
2.5 10.646 0.8 0.8 1 1.3 Lumpsum 10.646 Lumpsum 8.1892308
88.146 58.464231
3.0 = 99.26 kVA
4.0 = 0.71
5.0
5.1 = 100 kVA
5.2 = 4.5 %
5.3 = 22 KW5.4 = 0.415 kV
5.5 = 0.83
5.6 = 0.917
5.9 = 71.095 kVABase load on transformer before starting fourth
lar est motor(Rating in kVA of transformer assumed - Largest motor KVA)
1.7321 x V x p.f x efficiency
5.8 Rating of largest size motor in kVA = 28.905 kVAkW
P.F x Efficiency
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 40.212 AkW x 1000
Total Load
Crane
Exhaust Fan
82.72
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
Rating of the largest size motor From the above table
Considering 20% contingency
System P. F.
% impedance of transformer assumed From IS 2026
Lighting 12.80
7.28
4.73
- .
5.10 = 173.43 kVA
5.11 = 57.81 kVA
5.14 = 2222.2 kVA
The selected rating of transformer is 100 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 5.8
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 11.004 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
= 2.2222
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 3.0915
5.12 Fault Level at transformer secondary side
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.707
2 Total Working load 58 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 47 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 100
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 60
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 139.12
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
212.24
3 Current carring capacity of 3.5C x120 Sqmm = 223
4 No of cable required = 0.95
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x120 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 120 SQ = 0.21
3 X AT CONDUCTOR TEMP. (3.5C x 120 Qm = 0.0718
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.735363623
CABLE SIZE CHOSEN = 3.5CX120 sq.mm Al XLPE Cable
!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 16
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 55
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.952 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 12.85
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
20.50
3 Current carring capacity of 3C x10 Sqmm AL = 67
4 No of cable required = 0.31
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x10Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 10 SQmm = 3.94
3 X AT CONDUCTOR TEMP. (3C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.944690954
CABLE SIZE CHOSEN = 2X3CX10 sq.mm Al XLPE Cable
$!"#%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 29
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.952 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 23.29
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
37.15
3 Current carring capacity of 3C x10 Sqmm AL = 67
4 No of cable required = 0.55
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 10 SQmm = 3.94
3 X AT CONDUCTOR TEMP. (3C x 10 Qmm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.245274439
CABLE SIZE CHOSEN = 2X3CX10 sq.mm Al XLPE Cable
$!"#&&%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
565
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A) FEEDER DATA
1 WORKING LOAD (KW) 12
2 WORKING LOAD (KVA) = 15
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.952 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 20.87
2 CURRENT RATING REQ.AFTER CONSIDERING DERATIN = FULL LOAD CURRENT/DERATING FACTOR
33.28
3 Current carring capacity of 4C x10 Sqmm AL XLPE cable is = 67
4 No of cable required = 0.50
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 4C x10 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (4C x 10 SQmm AL XLPE Cable = 3.94
3 X AT CONDUCTOR TEMP. (4C x 10 Qmm AL XLPE Cable) = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.115594136
CABLE SIZE CHOSEN = 4CX10 sq.mm Al XLPE Cable
$!"#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
566
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 25
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 3.09
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 9.297701931
2 CABLE SIZE CHOSEN = 10 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 34.78
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
55.47
Considering 35% extra current 74.89
3 Current carring capacity of 3.5C x25 Sqmm = 96
4 No of cable required = 0.78
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x25 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 25 SQ = 3.94
3 X AT CONDUCTOR TEMP. (3.5C x 25 Qm = 0.0837
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.859323559
CABLE SIZE CHOSEN = 3.5CX25 sq.mm Al XLPE Cable
.
$!"#&'(
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
567
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.
2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 90 0.95 0.85 0.9 1 2 180 1 81
2.2 45 0.936 0.86 0.9 1 2 90 2 81
2.3 7.5 0.87 0.82 0.9 2 1 7.5 1 3.375
2.3 0.5 0.67 0.82 1 1 8 4 8 4
2.4 15 0.8 0.8 1 1.5 Lumpsum 15 Lumpsum 10
296.5 179.375
3.0 = 274.29 kVA
4.0 = 0.78
5.0
5.1 = 315 kVA
5.2 = 4.5 %
5.3 = 90 KW5.4 = 0.415 kV
5.5 = 0.85
5.6 = 0.95
5.9 = 203.54 kVA
5.10 = 668.73 kVA
5.11 = 222.91 kVA
5.14 = 7000 kVA
The selected rating of transformer is 315 kVA
%[Motor Starting kVA (S/D) + Base Load kVA] x 100
(within 10%)S.C capacity of transformer
5.16Voltage drop at transformer terminal when largest
motor start with Star-Delta starting= 6.1
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 12.461 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
= 7
S.C capacity of transformer
MVARating of transformer in MVA x 100
Impedance of transformer in %
kAFault Level in MVA
1.7321 x kV
Base load on transformer before starting largest
motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
5.13 Fault current of transformer secondary side (ISC) = 9.7382
5.12 Fault Level at transformer secondary side
1.7321 x V x p.f x efficiency
Motor starting Kva with Star-Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 111.46 kVAkW
P.F x Efficiency
P.F of largest size motor From the above table
Efficiency of largest size motor From the above table
5.7 FLC of motor = 155.05 AkW x 1000
Total Load
Crane
Exhaust Fan
228.57
Supply voltage System voltage
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 11/0.433KV,Dyn11,Delta-star)
Pump -1 100.31
= Diversity Factor
= Motor Efficiency
Item DescriptionRating in
kWEffi.
Working Load
(kVA)
Input Data and Calculations:
P. F.
Rating of the largest size motor From the above table
Considering 20% contingency
System P. F.
% impedance of transformer assumed From IS 2026
L. F. D. F.Connected Load Working Load
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
TRANSFORMER SIZING FOR KHORDA ( PHED) PUMPING STATION
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Lighting 15.63
7.28
4.73
Sr.
No.
Pump -2 100.63
568
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CAPACITOR BANK SIZING ACROSS BUS
1 Average Power factor (pf1) 0.785
2 Total Working load 179 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 105 KVAR
Working load ( Tan ( Cos -1 pf1) - Tan (Cos-1 pf2))
569
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 315
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 9.7385 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 29.30130143
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 438.24
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
668.56
3 Current carring capacity of 3.5C x240 Sqmm AL XLPE cable is = 326
4 No of cable required = 2.05
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x240 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 240 SQmm AL XLPE Cable) = 0.16
3 X AT CONDUCTOR TEMP. (3.5C x 240 Qmm AL XLPE Cable) = 0.071
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 2
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.468041806
CABLE SIZE CHOSEN = 2X3.5CX240 sq.mm Al XLPE Cable
!
(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE
570
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 112
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 9.73
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 55
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 29.27722971
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 89.97
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
143.49
3 Current carring capacity of 3C x50 Sqmm AL = 142
4 No of cable required = 1.01
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x50 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 50 SQmm = 0.82
3 X AT CONDUCTOR TEMP. (3C x 50 Qmm = 0.0754 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.447620248
CABLE SIZE CHOSEN = 2X3CX50 sq.mm Al XLPE Cable
"!#$%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
571
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 56
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 9.27
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 65
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 27.89310579
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (6 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 44.98
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
71.74
3 Current carring capacity of 3C x35 Sqmm AL = 117
4 No of cable required = 0.61
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x35 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 35 SQmm = 1.11
3 X AT CONDUCTOR TEMP. (3C x 35 Qmm = 0.07834 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 1.140931639
CABLE SIZE CHOSEN = 2X3CX35 sq.mm Al XLPE Cable
"!&'%
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
572
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 55
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 9.275 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 27.89310579
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 76.52
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
122.04
Considering 35% extra current 164.75
3 Current carring capacity of 3.5C x70 Sqmm AL XLPE cable is = 179
4 No of cable required = 0.92
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x70 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 70 SQmm AL XLPE Cable) = 0.567
3 X AT CONDUCTOR TEMP. (3.5C x 70 Qmm AL XLPE Cable) = 0.074
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.636144578
CABLE SIZE CHOSEN = 3.5CX70 sq.mm Al XLPE Cable
.
"!''(
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
573
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1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F.
D. F.
Effi.2.0
UnitTotal
(kW)Unit
Total
(kW)
2.1 132 0.957 0.86 0.9 1 3 396 2 237.6
2.2 Dewatering pump 1.5 0.79 0.81 1 1.5 1 1.5 1 1
2.3 EOT crane 15 0.902 0.81 0.9 2 1 15 1 6.75
2.4 Chain pully 3.7 0.83 0.82 0.9 2 1 3.7 1 1.665
2.5 Exhaust fan 0.5 0.67 0.82 1 1 6 3 6 3
2.6 Lighting (Indoor & Outdoor) 10 0.9 0.8 1 1.5 Lumsum 10 Lumsum 6.6666667
Total Load 429.2 256.68167
3.0 = 376.29 kVA
4.0 = 0.8186
5.0
5.1 = 400 kVA
5.2 = 4.5 %5.3 = 132 KW
5.4 = 0.415 kV
5.5 = 0.86
5.6 = 0.957
5.9 = 239.6150762 kVA
5.10 = 962.3095429 kVA
5.11 = 320.7698476 kVA
5.14 = 8888.888889 kVA
(within 10%)S.C capacity of transformer
The selected rating of transformer is 400 kVA
5.16 Voltage drop at transformer terminal when largestmotor start with Star Delta starting
= 6.3 % [Motor Starting kVA (S/D) + Base Load kVA] x 100
S.C capacity of transformer 1.7321 x kV x I SC
5.15Voltage drop at transformer terminal when largest
motor start with DOL starting= 13.52165196 %
[Motor Starting kVA (DOL) + Base Load kVA] x 100(within 10%)
S.C capacity of transformer
5.13 Fault current of transformer secondary side (ISC) = 12.36591962 kAFault Level in MVA
1.7321 x kV
5.12 Fault Level at transformer secondary side = 8.888888889 MVARating of transformer in MVA x 100
Impedance of transformer in %
Base load on transformer before starting fourth
largest motor(Rating in kVA of transformer assumed - Largest motor KVA)
Motor starting Kva with DOL start = 6 x 1.7321 x kV x I FLC
Motor starting Kva with Star Delta start = 3 x 1.7321 x kV x I FLC
5.8 Rating of largest size motor in kVA = 160.3849238 kVAkW
P.F x Efficiency
Efficiency of largest size motor From the above table
5.7 FLC of motor = 223.122046 AkW x 1000
1.7321 x V x p.f x efficiency
Rating of the largest size motor From the above table
Supply voltage System voltage
P.F of largest size motor From the above table
System P. F.
Calculation to check the starting of largest size motor
Rating of transformer assumed Nearest staanddard size (Confg. 33/0.433KV,Dyn11,Delta-star)
% impedance of transformer assumed From IS 2026
313.57
Considering 20% contingency
1.56
9.24
5.46
6.17
2.45
Sr.
No.Item Description
Rating in
kWEffi. P. F. L. F.
TRANSFORMER SIZING FOR RWPS PLANT
[ Working Load (kW) x L. F. ] / [ D. F. x P. F. x Effi. ] = Load Factor
Total Working Load (kW) / Total Working Load (kVA) = Motor Power Factor
= Diversity Factor
Vertcal Pump 288.69
= Motor EfficiencyInput Data and Calculations:
D. F.
Connected Load Working LoadWorking Load
(kVA)
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CAPACITOR BANK SIZING ACROSS BUS
Intermediate Pumping Station
1 Average Power factor (pf1) 0.819
2 Total Working load in IPS 257 kW
3 Power factor To be improved (pf2) 0.98
Total kVAR to be connected across Bus
4 Total kVAR to be connected across Bus 128 KVAR
Working load ( Tan ( Cos-1
pf1) - Tan (Cos-1
pf2))
575
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Short circuit calculation RWPS
Assumptions
1 Fault level at 220kV bus 20000 MVA (as per IS :2026)
2 Base MVA 2000
Ratio = 220kV / 132kV
Capacity = 100.00 MVA
Z= 9.27%
Qty 1 Nos
Considering negative tolerance Z = 8.34%
Net Z for transformers single transformer= 8.34%
3
Ratio = 132kV / 33kV
Capacity = 40.00 MVA
Z= 10.18%
Qty 1 Nos
Considering negative tolerance Z = 9.16%
Net Z for transformers single transformer= 9.16%
4
Line length = 18 kM
Conductor Type = DOG Assumed
Conductor Resiatance = 0.2733 ohm/kM
Z,Considering Reactance Negligible = 4.9194 ohm
5
Ratio = 33kV / 0.415kV
Capacity = 0.40 MVA
Z= 4.5%
Qty 1 Nos
Considering negative tolerance Z = 4.1%
Net Z for transformers single transformer= 4.1%
6 K' Constant for XLPE AL cable= 94
K' Constant for PVC AL cable= 75
K' Constant for PVC CU cable= 112
7 Fault clearing time for 33kV Breaker (t) = 1 Sec
Fault clearing t ime for 0.415kV ACB Breaker (t) = 0.08 Sec
Fault c learing t ime for 0.415kV MCCB Breaker (t) = 0.04 Sec
10 Starting Voltage dip = 15%
11 Starting current for DOL= 6 times
12 Starting current for Y-D= 2 times
13 Starting current for FCMA softstarter= 2.5 times
Formula used
1
2
3 Zline =
4 Zcable =
Transformer Details at Chandaka220KV/132KV
Transformer Details at Chandaka 132KV/33KV
33kV Over head line from Chandaka to CWPS
Transformer at CWPS
Zsource =Base MVA
Fault level at 220kV bus
Ztransformer =Base MVA
X tranformer Z%Transformer capacity in MVA
Base MVAX Line Z
kV2
Base MVAX Cable Z
kV2
576
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Calculation
a chandaka Grid Substation
220KV Bus 0.1 20000 52
220KV/132KV,100MVA transformer 1.7
1 132kV Bus 1.8 1130.8 5
2 132kV/33kV,40MVA transformer 4.6
3 33kV Bus 6.3 315.0 5.51
b RWPS
1 18 kM 33kV O/H line from Chandaka Substation to RWPS 9.03
2 33kV Bus 15.38 130.0 2.27 24.2
3 33kV/0.415kV, 0.4MVA transformer 202.50
4 0.415kV side of 0.4MVA transformer 217.88 9.2 12.77 38.4
(XLPE,AL,0.415kV)
5
0.415kV , XLPE ,3 X 3.5core x 185sqmm cable from
transformer to RWPS PMCC 30.07
6 RWPS PMCC 247.95 8.1 11.22 33.8
(,AL,0.415 kV)
7
0.415kV , XLPE ,3.5core x 50sqmm cable from RWPS
PMCC to RWPS Auxilary MCC 286.87
8 RWPS Auxilary MCC 534.82 3.7 5.20 11.1
Sr No Description
Impedance
" Z"
Fault level
"MVA"
Fault Current
"kA"
Minimum Cable
size "SQMM"
577
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 400
2 VOLTAGE (V) = 0.415
3 PF = 0.84 FAULT CURRENT Ish = 12.22
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 35
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 36.76955262
2 CABLE SIZE CHOSEN = 50 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in Ground (3 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 556.50
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
848.97
3 Current carring capacity of 3.5C x185 Sqmm AL XLPE cable is = 282
4 No of cable required = 3.01
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x185 Sqmm AL XLPE cable2 R AT CONDUCTOR TEMP. (3.5C x 185SQmm AL XLPE Cable) = 0.21
3 X AT CONDUCTOR TEMP. (3.5C x 185 Qmm AL XLPE Cable) = 0.0718
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 3
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.571949485
CABLE SIZE CHOSEN = 3X3.5CX185 sq.mm Al XLPE Cable
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
578
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A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 160
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 10.335 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 45
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 31.08260872
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 128.52
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
196.07
3 Current carring capacity of 3C x95 Sqmm AL XLPE cable is = 221
4 No of cable required = 0.89
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x95 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 70SQmm AL XLPE Cable) = 0.41
3 X AT CONDUCTOR TEMP. (3C x 70SQmm AL XLPE Cable) = 0.0724
4 COSø = 0.8
5 SINø = 0.66 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.896555308
CABLE SIZE CHOSEN = 2X3CX95 sq.mm Al XLPE Cable
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(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
579
7/30/2019 vd calculation
http://slidepdf.com/reader/full/vd-calculation 74/75
A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 59
2 VOLTAGE (V) = 0.415
3 PF = 0.8
4 FAULT CURRENT Ish = 10.33
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 30
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 31.08260872
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.69
3 OVERALL DERATING FACTOR = 0.6555
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 82.08
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
125.22
3 Current carring capacity of 3.5C x50 Sqmm AL XLPE cable is = 142
4 No of cable required = 0.88
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x50 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 50SQmm AL XLPE Cable) = 0.823 X AT CONDUCTOR TEMP. (3.5C x 50 Qmm AL XLPE Cable) = 0.075
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.720435477
CABLE SIZE CHOSEN = 3.5CX50 sq.mm Al XLPE Cable
$%&'(
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
580
7/30/2019 vd calculation
http://slidepdf.com/reader/full/vd-calculation 75/75
A) FEEDER DATA
1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 75
2VOLTAGE (V) = 0.4153 PF = 0.8
4 FAULT CURRENT Ish = 10.63
5 FAULT CLEARING TIME t = 0.08
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish*t/K
= 31.98529823
2 CABLE SIZE CHOSEN = 35 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABL = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.66
3 OVERALL DERATING FACTOR = 0.627
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE
= 104.34
2 CURRENT RATING REQ.AFTER CONSIDE = FULL LOAD CURRENT/DERATING FACTOR
166.42
Considering 35% extra current 224.66
3 Current carring capacity of 3.5C x95 Sqmm = 221
4 No of cable required = 1.02
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3.5C x95 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3.5C x 95 SQ = 0.41
3 X AT CONDUCTOR TEMP. (3.5C x 95 Qm = 0.0724
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.64701408
CABLE SIZE CHOSEN 3 5CX95 sq mm Al XLPE Cable
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(FULL LOAD CURRENT X LENGTH XIMPEDENCE)/NO OF RUNS X VOLTAGE