Page 821 - Basic Electrical Engineering

Thevenin’s equivalent resistance, R AB of the circuit by assuming zero
resistance of the voltage sources is calculated as shown in Fig. 11.13.

Figure 11.13

Let the open-circuit voltage across terminals A and B be E 0

Thevenin’s equivalent circuit can be represented as shown in Fig. 11.14.

Figure 11.14

The measured value by the voltmeter across terminals A and B is E .
m

E can be calculated as
m

Now, actual value of voltage across AB is E , its measured value is E .
m
0

Error in percentage