CT Ratio to Current Calculator

Formula

The formula to calculate the Primary Current from CT Ratio is:

\[ Ip = CT \cdot Is \]

Where:

\(Ip\) is the Primary Current (amps)
\(CT\) is the CT ratio
\(Is\) is the secondary current (amps)

What is a CT Ratio?

The CT ratio is the ratio of the primary current to the secondary current in a current transformer. It is used to measure high currents in a circuit by reducing them to a manageable level for measurement instruments.

Example Calculation 1

Let's assume the following values:

CT Ratio (CT) = 100
Secondary Current (Is) = 5 amps

Using the formula:

\[ Ip = 100 \cdot 5 = 500 \, \text{amps} \]

The Primary Current is 500 amps.

Example Calculation 2

Let's assume the following values:

CT Ratio (CT) = 200
Secondary Current (Is) = 1 amp

Using the formula:

\[ Ip = 200 \cdot 1 = 200 \, \text{amps} \]

The Primary Current is 200 amps.