Calculate Size of Diesel Generator having following Electrical Load. Consider Future Expansion ratio is
10%.Average use of Equipment is 0.8 (1 is Full Time Use)
4 No‘s of 1Ph, 230V, 80Watt CFL Bulbs, Diversity Factor is 0.8; Starting & Running P.F is 0.8.
2 No‘s of 1Ph, 230V, 3000Watt Air Condition, Diversity Factor is 1, Starting & Running P.F is 0.8.
2 No‘s of 1Ph, 230V, 500Watt Halogen Lights Diversity Factor is 0.8 Starting & Running P.F is 0.8.
1 No‘s of 1Ph,230V, 10KW Motor with Y-D Starter, Diversity Factor is 0.8,Starting P.F is 0.7 & Running P.F
is 0.8
1 No‘s of 3Ph,430V, 130KW Motor with Soft Starter , Diversity Factor is 0.8,Starting P.F is 0.7 & Running
P.F is 0.8
Load Calculation-1:
Full Load KW of CFL Bulb=(No X Watt X Diversity Factor) /1000
Full Load KW of CFL Bulb=(4x80x0.8)/1000=0.3KW
Full Load KVA of CFL Bulb=KW / P.F
Full Load KVA of CFL Bulb=0.3 / 0.8=0.4KVA----------- (H)
Full Load current of CFL Bulb=(No X Watt X Diversity Factor) / (Volt x P.F)
Full Load current of CFL Bulb=(4x80x0.8) / (230x0.8) =2 Amp----(M)
Type of Load=Linear
Starting KVA of CFL Bulb=1 X (KW / Starting P.F)
Starting KVA of CFL Bulb=0.3 / 0.8=0.4KVA--------------------- (1)
Starting Current=100% of Full Load Current.
Starting Current=1 X 2= 2 Amp-------------- (A)
Load Calculation-2:
Total Full Load KW of A.C=(No X Watt X Diversity Factor) /1000
Total Full Load KW of A.C =(2x3000x0.8)/1000=4.8KW
Total Full Load KVA of A.C =KW / P.F
Total Full Load KVA of A.C =4.8 / 0.8=6KVA----------- (I)
Total Full Load current of A.C =(No X Watt X Diversity Factor) / (Volt x P.F)
Total Full Load current of A.C =(2x3000x0.8) / (230x0.8) =26 Amp ------ (N)
Type of Load=Non Linear
Starting KVA of A.C=1.6 X (KW / Starting P.F)
Starting KVA of A.C =1.6 X (4.8 / 0.8)=9.6KVA ---------------------(2)
Starting Current=160% of Full Load Current.
Starting Current=1.6 X 26= 42 Amp-- (B)
Load Calculation-3:
Full Load KW of Halogen Bulb=(No X Watt X Diversity Factor) /1000
Full Load KW of Halogen Bulb=(2x500x0.8)/1000=0.8KW
Full Load KVA of Halogen Bulb=KW / P.F
Full Load KVA of Halogen Bulb=0.8 / 0.8=1KVA -----------(J)
Full Load current of Halogen Bulb=(No X Watt X Diversity Factor) / (Volt x P.F)
Full Load current of Halogen Bulb=(2x500x0.8) / (230x0.8) =4 Amp --- (O)
Type of Load=Non Linear
Starting KVA of Halogen Bulb =1.6 X (KW / Starting P.F) / Starting P.F
Starting KVA of Halogen Bulb =1.6 X (0.8 / 0.8)=1.6KVA ---------------------(3)
Starting Current=160% of Full Load Current.
Starting Current=1.6 X 4= 7 Amp ---------------(C)
Load Calculation-4:
Full Load KW of Motor=(No X Watt X Diversity Factor) /1000
Full Load KW of Motor =(1x10000x0.8)/1000=8KW
Full Load KVA of Motor =KW / P.F
Full Load KVA of Motor =8 / 0.8=10KVA -----------(K)
Full Load current of Motor =(No X Watt X Diversity Factor) / (Volt x P.F)
Full Load current of Motor =(1x10000x0.8) / (230x0.8) =43 Amp --- (P)
Type of Starter=Star-Delta
Starting KVA of Motor =4 X (KW / Starting P.F)
Starting KVA of Motor=4X (8 / 0.7)=45.7KVA -----------------------(4)
Starting Current=4 X Full Load Current
Starting Current=4 X 11.4 = 174 Amp --------------(D)
Load Calculation-5:
Full Load KW of Motor=(No X Watt X Diversity Factor) /1000
Full Load KW of Motor =(1x120000x0.8)/1000=96KW
Full Load KVA of Motor =KW / P.F
Full Load KVA of Motor =96 / 0.8=120KVA ----------- (L)
Full Load current of Motor =(No X Watt X Diversity Factor) / (Volt x P.F)
Full Load current of Motor =(1x120000x0.8) / (1.732x430x0.8) =167 Amp----(Q)
Type of Starter=Auto Transformer
Starting KVA of Motor =3 X (KW / Starting P.F)
Starting KVA of Motor=3 X (96 / 0.7)=411.4KVA -------------- (5)
Starting Current=3 X Full Load Current
Starting Current=3 X 167 = 501 Amp--(E)
Total Load Calculation:
Total Starting KVA = (1) + (2) +(3) + (4) + (5)
Total Starting KVA
=0.4+9.6+1.6+45.7+411.4 =468.7 KVA
Total Starting Current = (A) + (B) +(C) + (D) + E
Total Starting Current
=2+42+7+174+501= 725 Amp
Total Running KVA =(H)+(I)+(J)+(K)+(L)
Total Running KVA =0.4+6+1+10+120= 137KVA
Total Running Current=(M)+(N)+(O)+(P)+(Q)
Total Running Current=2+26+4+43+167= 242 Amp
Size of Diesel Generator= Starting KVA X Future Expansion X Average Use of Equipments
Size of Diesel Generator=468 X 1.1 X 0.8
Size of Diesel Generator= 412 KVA
Summary:
Total Starting KVA =468.7 KVA
Total Starting Current =725 Amp
Total Running KVA = 137KVA
Total Running Current= 242 Amp
Size of Diesel Generator= 412 KVA