CT Ratio Calculator

CT ratio calculator can be used to determine the current transformer ratio based on primary and secondary currents.

Input Parameters

Calculation Results

CT Ratio

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Where:
CT Ratio = Primary Current / Secondary Current

Calculation Formula

CT Ratio = N₁/N₂ = I₂/I₁

Where:
N₁ = Number of turns in primary winding
N₂ = Number of turns in secondary winding
I₁ = Primary Current
I₂ = Secondary Current

CT Ratio Calculator Usage Guide

Learn how to use the CT ratio calculator and its working principles

How to Use the CT Ratio Calculator

  1. Enter the primary current in Amperes (A)
  2. Enter the secondary current in Amperes (A)
  3. Click the "Calculate" button to compute the CT ratio
  4. The result will be displayed as "N₁ : N₂"

Working Principle

A Current Transformer (CT) is a device that produces a reduced current accurately proportional to the current in the circuit, which is being measured. The CT ratio is defined as the ratio of the primary current to the secondary current and is expressed as N₁ : N₂.

The formula used for calculating the CT ratio is:

CT Ratio = N₁/N₂ = I₂/I₁

where:
  • N₁ = Number of turns in primary winding
  • N₂ = Number of turns in secondary winding
  • I₁ = Primary Current
  • I₂ = Secondary Current

Applications

CT ratios are crucial in electrical systems for various applications including:

  • Measuring high currents in electrical power systems
  • Protecting electrical equipment from overcurrent
  • Safely monitoring current in industrial and commercial settings

Example

If the primary current is 1000A and the secondary current is 5A, the CT ratio would be:

CT Ratio = 1000A / 5A = 200 : 1