SECTION-9
1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F. D. F. Effi. 2.0 Unit Total (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 kVA 5.2 = 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 5.16 Voltage 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
5.15 Voltage 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 kA
Fault Level in MVA 1.7321 x kV
5.12 Fault Level at transformer secondary side = 25 MVA Rating 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 started)
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 kVA kW
P.F x Efficiency
5.7 FLC of motor = 60.92016454 A kW 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 Load
Working Load (kVA)
Pump 626.79
Sr.
No. Item Description
Rating in
kW Effi. P. F. L. F.
= Motor Efficiency Input 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
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. (I
NLC)
19.190
35% of FLC
10 Motor magnetising current in amp.
19.094
= [ I
NLCx sin(cos
-1p.f
NL) ]
11 Capacitor current (Ic)
17.184
Shall be 90% of motor magnetising current
12
Max. kVAR that can be connected across motor
terminal
98.22
= (1.7321 x V x Ic) / 1000
13
Total kVAR to be connected across the motor
terminal
105.00
= kW[ tan(cos
-1
p.f
1) - tan(cos
-1p.f
2) ]
14
Excess kVAR to be connected across the
switchgear bus bars (13 - 12)
6.79
Negative value indicates capacitor bank is not
required across the bus.
1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F. D. F. Effi. 2.0 Unit Total (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 Efficiency Input Data and Calculations:
D. F.
Connected Load Working Load
Working 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 kW Effi. 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 A kW x 1000
1.7321 x V x p.f x efficiency
5.8 Rating of largest size motor in kVA = 193.3955422 kVA kW
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 MVA Rating of transformer in MVA x 100
Impedance of transformer in % 5.13 Fault current of transformer secondary side (ISC) = 9.738161699 kA Fault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15 Voltage 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 5.16 Voltage 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
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
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
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"
A) FEEDER DATA 1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 1250
2 VOLTAGE (V) = 3.3
3 PF = 0.8
4 FAULT CURRENT Ish = 4.07
5 FAULT CLEARING TIME t = 1
6 CONSTANT K = 94
7 LENGTH = 70
B)
1 AREA OF CONDUCTOR = Ish* t/K
= 43.2978723
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 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
= 218.70
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
333.64
3 Current carring capacity of 3C x300 Sqmm AL XLPE cable is = 360
4 No of cable required = 0.93
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x300 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 300SQmm AL XLPE Cable) = 0.13 3 X AT CONDUCTOR TEMP. (3C x 300SQmm AL XLPE Cable) = 0.072
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.11827365
CABLE SIZE CHOSEN = 3CX300 sq.mm Al XLPE Cable
! " #$#
%&" '(
(FULL LOAD CURRENT X LENGTH X IMPEDENCE)/NO OF RUNS X VOLTAGE
A) FEEDER DATA 1 WORKING LOAD (KW)
2 WORKING LOAD (KVA) = 349
2 VOLTAGE (V) = 3.3
3 PF = 0.8
4 FAULT CURRENT Ish = 3.98
5 FAULT CLEARING TIME t = 1
6 CONSTANT K = 94
7 LENGTH = 40
B)
1 AREA OF CONDUCTOR = Ish* t/K
= 42.34042553
2 CABLE SIZE CHOSEN = 50 SQ.MM AL
(AS PER SHORT CIRCUIT CALCULATION)
C) LAYING CONDITIONS
1 AMBIENT AIR TEMPERATURE = 45
RATING FACTOR = 0.95
2 GROUPING/SPACING WITH OTHER CABLES = Cable laid in trench (9 cables touching)
RATING FACTOR = 0.76
3 OVERALL DERATING FACTOR = 0.722
D)
1 FULL LOAD CURRENT Ifl = WORLING LOAD (KVA)/1.732 x VOLTAGE x 1.732
= 35.25
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING = FULL LOAD CURRENT/DERATING FACTOR
48.83
3 Current carring capacity of 3.5C x50 Sqmm AL XLPE cable is = 120
4 No of cable required = 0.41
E) CHECK FOR VOLTAGE DROP
1 CABLE SIZE = 3C x50 Sqmm AL XLPE cable
2 R AT CONDUCTOR TEMP. (3C x 50 SQmm AL XLPE Cable) = 0.82 3 X AT CONDUCTOR TEMP. (3C x 50 Qmm AL XLPE Cable) = 0.086
4 COSø = 0.8
5 SINø = 0.6
6 No of runs: = 1
% VOLTAGE DROP =
7 % VOLTAGE DROP = 0.052371797
CABLE SIZE CHOSEN = 3.5CX50 sq.mm Al XLPE Cable
#$#
%&" '(
"
)
* + "
(FULL LOAD CURRENT X LENGTH X IMPEDENCE)/NO OF RUNS X VOLTAGE
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 time 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 =
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 MVA
X Line Z kV2
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"
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 = 10.27
5 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 = 0.6
6 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
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 = 8.93
5 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
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 = 8.93
5 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 = 0.6
6 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
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 = 8.93
5 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
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 = 3.39
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 = 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
A) FEEDER DATA
1 WORKING LOAD (KW)
5.6
2 WORKING LOAD (KVA)
=
7
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
=
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
=
9.74
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING
=
FULL LOAD CURRENT/DERATING FACTOR
18.98
3 Current carring capacity of 4C x16 Sqmm AL XLPE cable is
=
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 Cable) =
2.44
3 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
=
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
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) = 2.44 3 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
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 = 8.93
5 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
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
=
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 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
=
0.438263899
CABLE SIZE CHOSEN
=
3.5CX120
sq.mm Al XLPE Cable
!"
#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
A) FEEDER DATA
1
WORKING LOAD (KW)
2
WORKING LOAD (KVA)
=
29
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
=
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
=
0.95
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
=
40.35
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING
=
FULL LOAD CURRENT/DERATING FACTOR
64.35
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is
=
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 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
=
0.6
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
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 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
=
22.26
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING
=
FULL LOAD CURRENT/DERATING FACTOR
35.50
3 Current carring capacity of 3C x10 Sqmm AL XLPE cable is
=
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 SQmm AL XLPE Cable)
=
3.94
3 X AT CONDUCTOR TEMP. (3C 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
=
1.636204732
CABLE SIZE CHOSEN
=
2X3CX10
sq.mm Al XLPE Cable
$
!"
#
&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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
=
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 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
=
1.301526492
CABLE SIZE CHOSEN
=
4CX10
sq.mm Al XLPE Cable
$
!"
#
%
'
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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
=
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 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 x10 Sqmm AL XLPE cable is
=
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 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
=
0.697246335
CABLE SIZE CHOSEN
=
4CX10
sq.mm Al XLPE Cable
$
!"
#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F. D. F. Effi. 2.0 Unit Total (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 KW 5.4 = 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 Description Rating in kW Effi.
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 A kW 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 kVA kW
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
MVA Rating of transformer in MVA x 100
Impedance of transformer in %
kA Fault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15 Voltage 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
5.16 Voltage drop at transformer terminal when largest
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
1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F. D. F. Effi. 2.0 Unit Total (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 KW 5.4 = 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 Description Rating in kW Effi.
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 A kW 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 kVA kW
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
MVA Rating of transformer in MVA x 100
Impedance of transformer in %
kA Fault Level in MVA
1.7321 x kV
S.C capacity of transformer 1.7321 x kV x I SC
5.15 Voltage 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
5.16 Voltage drop at transformer terminal when largest
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
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
=
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 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
=
0.438263899
CABLE SIZE CHOSEN
=
3.5CX120
sq.mm Al XLPE Cable
!"
#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
A) FEEDER DATA
1
WORKING LOAD (KW)
2
WORKING LOAD (KVA)
=
29
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
=
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
=
0.95
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
=
40.35
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING
=
FULL LOAD CURRENT/DERATING FACTOR
64.35
3 Current carring capacity of 3C x16 Sqmm AL XLPE cable is
=
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 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
=
0.6
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
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 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
=
22.26
2 CURRENT RATING REQ.AFTER CONSIDERING DERATING
=
FULL LOAD CURRENT/DERATING FACTOR
35.50
3 Current carring capacity of 3C x10 Sqmm AL XLPE cable is
=
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 SQmm AL XLPE Cable)
=
3.94
3 X AT CONDUCTOR TEMP. (3C 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
=
1.636204732
$
!"
#
&
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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
=
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 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
=
1.301526492
CABLE SIZE CHOSEN
=
4CX10
sq.mm Al XLPE Cable
$
!"
#
%
'
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
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
=
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 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 x10 Sqmm AL XLPE cable is
=
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 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
=
0.697246335
CABLE SIZE CHOSEN
=
4CX10
sq.mm Al XLPE Cable
$
!"
#
(FULL LOAD CURRENT X LENGTH X
IMPEDENCE)/NO OF RUNS X VOLTAGE
1.0 Formula Used:
1.1 Working Load in kVA = L. F.
1.2 System P. F. = P. F. D. F. Effi. 2.0 Unit Total (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 5.16 Voltage 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
5.15 Voltage 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
MVA Rating 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) = 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 kVA kW
P.F x Efficiency Base load on transformer before starting fourth
largest motor
5.7 FLC of motor = 77.771 A kW 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 in kW 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
5.46 Exhaust Fan (existing)
3.67 Chain pully (existing)
50.31
Sr.
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
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
