import math
#initialisation of variables
i=5.0
L=5*(10**6)
C=0.01
#Calculations
e=i*math.sqrt(L/C)
#Results
print("The voltage appearing across the pole of C.B.=%.2f V " %e)
R=0.5*math.sqrt(L/C)
print("The value of resistance to be used across contacts, R=%.2f ohms" %R)
import math
#initialisation of variables
Vnl=132*math.sqrt(2)/math.sqrt(3) #peak value of peak to neutral voltage(kV)
Vr1=Vnl*.95 #recovery voltage (kV)
#Calculations
Vr=102.4*.916 # active recovery voltage(kV)
Vrmax=2.0*Vr
fn=16.0*(10**3)
t=1.0/(2*fn)
RRRV=Vrmax*(10**-6)/t
#Results
print("Rate of rise of restriking voltage, RRRV = %.0f kV/micro-sec " %RRRV)
import math
#initialisation of variables
Vm=132*math.sqrt(2)/math.sqrt(3)
K1=0.9
K2=1.5
K=K1*K2
sinq=0.92
#Calculations
Vr=K*Vm*sinq
fn=16*(10**3)
RRRV=2*Vr*(10**-6)*fn*2
#Results
print("Average rate of rise of restriking voltage,RRRV=%.3f kV/micro-sec" %RRRV)
import math
#initialisation of variables
In=1500.0
#Calculations
Ib=2000/(math.sqrt(3.0)*33.0)
Im=2.55*Ib
Is=Ib
#Results
print("rated normal current=%.0f amps" %In)
print("Breaking current=%.2f KA" %Ib)
print("Making current =%.2f kA" %Im)
print("Short time rating for 3 sec=%.2f kA " %Is)
import math
#initialisation of variables
MVA=10.0
Is=MVA*1000/(math.sqrt(3)*13.8)
print("(i)sustained short circuit current in the breaker =%.0f amps" %Is)
MVA1=100.0
Isc=MVA1*1000.0/(math.sqrt(3)*13.8)
#Calculations
print("(ii)initial symmetrical r.m.s current in the breaker r.m.s=%.0f amps" %Isc)
Im=math.sqrt(2)*Isc
print("(iii)maximum possible d.c component of the short circuit current in the breaker =%.0f amps" %Im)
Im2=1.6*Isc
print("(iv)momentary current rating of the breaker=%.0f amps" %Im2)
Ib=1.2*Isc
print("(v)the current to be interrupted by the breaker =%.0f amps" %Ib)
KVA=math.sqrt(3)*13.8*5016
#Results
print("(vi)the interupting =%.0f KVA"%KVA)
#Answers don't match due to difference in rounding off of digits