3-24
Figure 3-31A.—RL circuit.
The secondary load impedance, R2, affects the primary impedance through reflection from
secondary to primary. If the load on the secondary is increased (R2 decreased), the load on the primary is
also increased and primary and secondary currents are increased.
T1 can be shown as an inductor and R1-R2 as a combined or equivalent series resistance (RE) since
T1 has an effective inductance and any change in R1 or R2 will change the current. The equivalent circuit
is shown in figure 3-31, view (B). It acts as a series RL circuit and will be discussed in those terms.
Figure 3-31B.—RL circuit.
