Question

A multipurpose transformer has a secondary coil with several points at which a voltage can be extracted, giving outputs of 5.60, 12.0, and 480 V. (a) The input voltage is 220 V to a primary coil of 230 turns. What are the numbers of turns in the parts of the secondary used to produce the output voltages

Answer 1

Step-by-step explanation:

A multipurpose transformer can act as step up as well as step down transformer according to the desired setting by a user.

When the voltage at the output is greater than the voltage at the input of the transformer then it acts as step-up transformer and vice-versa acting is a step down transformer.

Given that:

input (primary) voltage of the transformer,
`V_i=220~V`

no. of turns in the primary coil,
`N_i=230`

• When the output voltage is 5.60 V:

`V_o=5.60~V`

`(N_i)/(N_o) =(V_i)/(V_o)`

`(N_o)/(230)=(5.60)/(220)`

`N_o=5.85\approx 6` turns compensating the losses

• When the output voltage is 12.0 V:

`V_o=12.0~V`

`(N_i)/(N_o) =(V_i)/(V_o)`

`(N_o)/(230)=(12.0)/(220)`

`N_o=12.45\approx 13` turns compensating the losses

• When the output voltage is 480 V:

`V_o=480~V`

`(N_i)/(N_o) =(V_i)/(V_o)`

`(N_o)/(230)=(480)/(220)`

`N_o=501.8\approx 502` turns compensating the losses