Battery Sizing

NICKEL CADMIUM BATTERY & CHARGER SIZING CALCULATION FOR STATIONARY APPLICATIONS (ELECTRICAL SUBSTATION) AS PER IEEE STD. 1115-2000 BATTERY DATA Nominal System Voltage Maximum Allowable System Voltage Minimum Battery Voltage Design Margin Aging Factor Cell Discharge-End Voltage Number of Cells Number of Battery Bank Total Number of Cells

110 125 99 99 99 1.14 87 2 174

V V V

V Cells Banks Cells

LOAD PROFILE Period A1 A2 A3 A4 A5 A6 A7

Load (A) 320.000 100.000 280.000 200.000 40.000 120.000 100.000

Duration of Load (Minute) M1 M2 M3 M4 M5 M6 M7

0.080 29.920 30.000 60.000 59.420 0.580 1.000

CALCULATION -1 Period

-2

Load

-3 Change in Load

-4 Duration of Load

-5

-6 -7 Capacity Rating Temparature Factor at t Derating Factor Minute Rate for t Minute (Tt) (Kt)

Time to End of Section

(amperes) (amperes) (minutes) Section 1 - First Period Only - If A2 is greater than A1, go to Section 2 1 320.00 A1-0 = 320 M1= 0.080 t1 = M1 = A1=

(minutes)

-8 Required Section Size (3) x (6) x (7) Rated Amp Hrs (Ah) Positive Values

=

Negative Values

0.08

0.432 Section 1

1.230 Total

170.035 170.035

Section 2 - First Two Periods Only - If A3 is greater than A2, go to Section 3 1 A1= 320.00 A1-0 = 320 M1= 0.080 t1 = M1+M2 = 2 A2= 100.00 A2-A1= -220 M2= 29.920 t2 = M2 =

30.00 29.92

1.000 1.000 Section 2

1.000 1.000 Sub Total Total

320.000 0.000 320.000 490.035

0.000 -220.000 -220.000

Section 3 - First Three Periods Only - If A4 is greater than A3, go to Section 4 1 A1= 320.00 A1-0 = 320 M1= 0.080 t1 = M1+M2+M3= 2 A2= 100.00 A2-A1= -220 M2= 29.920 t2 = M2+M3 = 3 A3= 280.00 A3-A2= 180 M3= 30.000 t3 = M3 =

60.00 59.92 30.00

1.780 1.779 1.000 Section 3

1.500 1.500 1.000 Sub Total Total

854.400 0.000 180.000 1,034.400 447.330

0.000 -587.070 0.000 -587.070

Section 4 - First Four Periods Only - If A5 is greater than A4, go to Section 5 1 A1= 320.00 A1-0 = 320.00 M1= 0.080 t1 = M1+M2+M3+M4= 2 A2= 100.00 A2-A1= -220.00 M2= 29.920 t2 = M2+M3+M4 = 3 A3= 280.00 A3-A2= 180.00 M3= 30.000 t3 = M3+M4 = 4 A4= 200.00 A4-A3= -80.00 M4= 60.000 t4 = M4 =

120.00 119.92 90.00 60.00

1.000 1.000 1.000 1.000 Section 4

1.000 1.000 1.000 1.000 Sub Total Total

320.000 0.000 180.000 0.000 500.000 200.000

0.000 -220.000 0.000 -80.000 -300.000

Section 5 - First Five Periods Only - If A6 is greater than A5, go to Section 6 1 A1= 320.00 A1-0 = 320.00 M1= 0.080 t1 = M1+M2+M3+M4+M5= 2 A2= 100.00 A2-A1= -220.00 M2= 29.920 t2 = M2+M3+M4+M5 = 3 A3= 280.00 A3-A2= 180.00 M3= 30.000 t3 = M3+M4+M5 = 4 A4= 200.00 A4-A3= -80.00 M4= 60.000 t4 = M4+M5 = 5 A5= 40.00 A5-A4= -160.00 M5= 59.420 t5 = M5 =

179.42 179.34 149.42 119.42 59.42

1.000 1.000 1.000 1.000 1.000 Section 5

1.000 1.000 1.000 1.000 1.000 Sub Total Total

320.000 0.000 180.000 0.000 0.000 500.000 40.000

0.000 -220.000 0.000 -80.000 -160.000 -460.000

Section 6 - First Six Periods Only - If A7 is greater than A6, go to Section 7 1 A1= 320.00 A1-0 = 320.00 M1= 0.080 t1 = M1+M2+M3+M4+M5+M6= 2 A2= 100.00 A2-A1= -220.00 M2= 29.920 t2 = M2+M3+M4+M5+M6 = 3 A3= 280.00 A3-A2= 180.00 M3= 30.000 t3 = M3+M4+M5+M6 = 4 A4= 200.00 A4-A3= -80.00 M4= 60.000 t4 = M4+M5+M6 = 5 A5= 40.00 A5-A4= -160.00 M5= 59.420 t5 = M5+M6 = 6 A6= 120.00 A6-A5= 80.00 M6= 0.580 t6 = M6 =

180.00 179.92 150.00 120.00 60.00 0.58

1.000 1.000 1.000 1.000 1.000 1.000 Section 6

1.000 1.000 1.000 1.000 1.000 1.000 Sub Total Total

320.000 0.000 180.000 0.000 0.000 80.000 580.000 120.000

0.000 -220.000 0.000 -80.000 -160.000 0.000 -460.000

Section 7 - First Seven Periods Only - If A8 is greater than A7, go to Section 8 1 A1= 320.00 A1-0 = 320.00 M1= 0.080 t1 = M1+M2+M3+M4+M5+M6+M7= 2 A2= 100.00 A2-A1= -220.00 M2= 29.920 t2 = M2+M3+M4+M5+M6+M7 = 3 A3= 280.00 A3-A2= 180.00 M3= 30.000 t3 = M3+M4+M5+M6+M7 = 4 A4= 200.00 A4-A3= -80.00 M4= 60.000 t4 = M4+M5+M6+M7 = 5 A5= 40.00 A5-A4= -160.00 M5= 59.420 t5 = M5+M6+M7 = 6 A6= 120.00 A6-A5= 80.00 M6= 0.580 t6 = M6+M7 = 7 A7= 0.00 A7-A6= -120.00 M7= 0.000 t7 = M7 =

180.00 179.92 150.00 120.00 60.00 0.58 0.00

1.000 1.000 1.000 1.000 1.000 1.000 1.000 Section 7

1.000 1.000 1.000 1.000 1.000 1.000 1.000 Sub Total Total

320.000 0.000 180.000 0.000 0.000 80.000 0.000 580.000 0.000

0.000 -220.000 0.000 -80.000 -160.000 0.000 -120.000 -580.000

Note: The battery with Ah capacity nearest to 432.74Ah is KM438P with actual Ah capacity of 438Ah.