Enter the primary voltage (volts), the primary current (amps), and the secondary current (amps) into the calculator to determine the Secondary Voltage. 

Secondary Voltage Formula

The following formula is used to calculate the Secondary Voltage.

V2 = V1 * I1 / I2
  • Where V2 is the Secondary Voltage (volts)
  • V1 is the primary voltage (volts) 
  • I1 is the primary current (amps) 
  • I2 is the secondary current (amps) 

To calculate the secondary voltage, multiply the primary voltage by the primary current, then divide by the secondary current.

How to Calculate Secondary Voltage?

The following example problems outline how to calculate Secondary Voltage.

Example Problem #1

  1. First, determine the primary voltage (volts). In this example, the primary voltage (volts) is determined to be 300 .
  2. Next, determine the primary current (amps). For this problem, the primary current (amps) is measured to be 2 .
  3. Next, determine the secondary current (amps). In this case, the secondary current (amps) is found to be 3.
  4. Finally, calculate the Secondary Voltage using the formula above: 

V2 = V1 * I1 / I2

Inserting the values from above and solving the equation yields: 

V2 = 300 * 2 / 3 = 200 (volts)

Example Problem #2

Using the same method as above, determine the variables required by the equation. For this example problem, these are:

primary voltage (volts) = 500

primary current (amps) = 4

secondary current (amps) = 2

Enter these given values into the calculator or above yields: 

V2 = 500 * 4 / 2 = 1000 (volts)