Chapter 21, Problem 32P

To determine

The output voltage and input current of a transformer.

Answer to Problem 32P

Solution:

Output voltage of transformer ${\text{V}}_{\text{s}}\text{= 450 V}$

Input current of transformer ${\text{I}}_{\text{p}}\text{= 56}\text{.36 A}$

Explanation of Solution

Given info:

No.of Primary turns $\left({\text{N}}_{\text{p}}\right)\text{ = 330}$

No.of secondary turns $\left({\text{N}}_s\right)\text{ = 1240 }$

Input voltage $\text{= 120 V}$

Output current (Is)$\text{=15}\text{.0 A}$

Formula to be used:

As per the voltage ratio formula with respect to turns

$\frac{{\text{V}}_{\text{s}}}{{\text{V}}_{\text{p}}}\text{=}\frac{{\text{N}}_{\text{s}}}{{\text{N}}_{\text{p}}}$

Calculation:

$\begin{array}{l}\Rightarrow {\text{V}}_{\text{s}}{\text{=V}}_{\text{p}}\text{×}\frac{{\text{N}}_{\text{s}}}{{\text{N}}_{\text{p}}}\\ \text{ =120×}\frac{\text{1240}}{\text{330}}\\ \text{ =450 V}\end{array}$

Formula to be used:

As per the current ratio formula with respect to turns,

$\frac{{\text{I}}_{\text{s}}}{{\text{I}}_{\text{p}}}\text{=}\frac{{\text{N}}_{\text{p}}}{{\text{N}}_{\text{s}}}$

Calculation:

$\begin{array}{l}\Rightarrow {\text{I}}_{\text{p}}{\text{= I}}_{\text{s}}\text{×}\frac{{\text{N}}_{\text{s}}}{{\text{N}}_{\text{p}}}\\ \text{ =15×}\frac{\text{1240}}{\text{330}}\\ \text{ =56}\text{.36 A}\end{array}$