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//===========================================================================
//chapter 6 example 8
clc;clear all;
//variable decalaration
Rm = 5; //coil resistance in Ω
Rm1 = 0.00075; //coil resistance in Ω
Im = 0.015; //full-scale defelction current in A
I = 100; //current to be measured in A
T1 = 0.004; //temperature coeficient of copper in Ω/Ω/°C
T2 = 0.00015; //temperature coeficient of manganin in Ω/Ω/°C
T =10; //rise in temperature in °C
//calculations
N = I/(Im); //multiplying power of shunt
Rs = Rm/(N-1); //resistance of manganin shunt in Ω
Rc = Rm*(1+(T1*T)); //coil resitance with 10°C in temperature in Ω
Rsh = Rm1*(1+(T2*T)); //shunt resitance with 10°C in temperature in Ω
In = (Rsh/((Rc+Rsh)))*100; //new instrument current in A
r = (In/(Im))*100; //new instrument reading in A
e = ((r-I)/(I))*100; //percentage error in %
//result
mprintf('percentage error %3.3f percentage",e);
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