Transformer calculator -full load current and turns ratio

The transformer calculator calculates the primary and secondary full load current, and turns, ratio of a single or 3-phase transformer.
Phase

Transformer rating
 
Primary voltage (V)

Secondary voltage (V)

Parameters

How to calculate transformer primary full load current?

The primary winding full load current Ip is calculated as:

\( I_{p}= \dfrac{S}{\sqrt{3} V_{p}} \)

Where,

How to calculate transformer secondary full load current?

The secondary winding full load current Is is calculated as:

\( I_{s}= \dfrac{S}{\sqrt{3} V_{s}} \)

Where,

How to calculate transformer turns ratio?

The transformer turns ratio n is calculated as:

\( n = \dfrac{ V_{p} }{ V_{s} } \), Where,

Example 1: Calculate transformer full load current

Calculate the secondary full load current of a a 200 kVA, 11 kV to 420 V, step down transformer.

\( I_{s}= \dfrac{200000}{\sqrt{3} \cdot 420} \)

\( I_{s}= 275 \textrm{ A} \)

Example 2: Calculate transformer turns ratio

Calculate the secondary full load current of a a 200 kVA, 11 kV to 420 V, step down transformer.

\( n = \dfrac{11000}{420} \)

\( n = 26.2 \)

Thanks for using my calculator.

Please send any comments or questions to admin@jcalc.net.