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Transformer Formula Calculator

\[ V_S = V_P \frac{N_S}{N_P} \]

1. What is the Transformer Formula Calculator?

Definition: This calculator computes the secondary voltage (\(V_S\)) of a transformer, given the primary voltage (\(V_P\)), the number of primary turns (\(N_P\)), and the number of secondary turns (\(N_S\)).

Purpose: It is used in electrical engineering to determine the output voltage of a transformer, essential for designing power supplies, electrical grids, and electronic devices.

2. How Does the Calculator Work?

The calculator uses the transformer voltage ratio formula:

Formula: \[ V_S = V_P \frac{N_S}{N_P} \] where:

  • \(V_S\): Secondary voltage (V, kV, mV)
  • \(V_P\): Primary voltage (V, kV, mV)
  • \(N_S\): Number of secondary turns (unitless)
  • \(N_P\): Number of primary turns (unitless)

Unit Conversions:

  • Voltage (Primary and Secondary):
    • 1 V = 1 V
    • 1 kV = 1000 V
    • 1 mV = 0.001 V

Steps:

  • Enter the primary voltage in V, kV, or mV (default 120 V, step size 0.00001).
  • Enter the number of primary turns (default 200, step size 1).
  • Enter the number of secondary turns (default 100, step size 1).
  • Convert primary voltage to base unit (V).
  • Validate that the number of turns are positive integers.
  • Calculate secondary voltage: \(V_S = V_P \frac{N_S}{N_P}\).
  • Convert the secondary voltage to the selected unit.
  • Display the result, rounded to 4 decimal places.

3. Importance of Transformer Voltage Calculation

Calculating the secondary voltage of a transformer is crucial for:

  • Electrical Engineering: Designing transformers to step up or step down voltage for power distribution.
  • Electronics: Ensuring appropriate voltage levels for circuits in devices like chargers and appliances.
  • Education: Teaching principles of electromagnetic induction and transformer operation in physics and engineering.

4. Using the Calculator

Examples:

  • Example 1: Calculate the secondary voltage for \(V_P = 120 \, \text{V}\), \(N_P = 200\), \(N_S = 100\), in V:
    • Enter \(V_P = 120 \, \text{V}\), \(N_P = 200\), \(N_S = 100\).
    • Secondary voltage: \(V_S = 120 \times \frac{100}{200} = 60 \, \text{V}\).
    • Result: \( \text{Secondary Voltage} = 60.0000 \, \text{V} \).
  • Example 2: Calculate the secondary voltage for \(V_P = 230 \, \text{V}\), \(N_P = 500\), \(N_S = 50\), in mV:
    • Enter \(V_P = 230 \, \text{V}\), \(N_P = 500\), \(N_S = 50\).
    • Secondary voltage: \(V_S = 230 \times \frac{50}{500} = 23 \, \text{V} = 23000 \, \text{mV}\).
    • Result: \( \text{Secondary Voltage} = 23000.0000 \, \text{mV} \).

5. Frequently Asked Questions (FAQ)

Q: What is a transformer?
A: A transformer is an electrical device that transfers electrical energy between two circuits by changing voltage levels through electromagnetic induction.

Q: Why must the number of turns be positive integers?
A: The number of turns represents the number of loops in the transformer coils, which must be positive integers for a physically realistic transformer.

Q: What happens if \(N_S > N_P\)?
A: If \(N_S > N_P\), the transformer steps up the voltage (\(V_S > V_P\)); if \(N_S < N_P\), it steps down the voltage (\(V_S < V_P\)).

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