Transformer Full Load Current and Turns Ratio Calculator

Welcome! This page is about the calculation the primary and secondary current of a single or 3 phase transformer and the turns ratio. The key parameters required for calculation will be:
Phase (Single or 3-Phase) 
Transformer Power Rating (VA, kVA, MVA) 
Primary voltage (Vp)
Secondary voltage (Vs)
Let's begin! 
CalculationInputs﻿﻿S 
:1000VA​
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﻿﻿V_p
:230volts​
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﻿﻿V_s
:115volts​
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Output﻿﻿I_p_3P 
:2.5102922ampere​
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﻿﻿I_p_1P
:4.34782609ampere​
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﻿﻿I_s_3P
:5.02043712ampere​
﻿
﻿﻿I_s_1P
:8.69565217ampere​
﻿
﻿﻿n 
:2​
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ExplanationWhat is a transformer?The transformer is a device that transfers electrical energy from one circuit to another through electromagnetic induction. The transformer relies on the principles of Faraday's Law of Electromagnetic Induction, which states that the voltage induced in a conductor is proportional to the rate of change of the magnetic field. We will calculate a transformer's full load current and turns ratio in this template.
What is the full load current? The full load current of a transformer is the amount of current that the transformer can carry under normal operating conditions. It is an important parameter to consider when designing a transformer as it determines the conductor's size needed to carry the current.
What is the turn ratio? The turns ratio of a transformer is the ratio of the number of turns of wire on the primary winding of the transformer to the number of turns on the secondary winding. It is an important parameter to consider as it determines the voltage transformation the transformer can perform.
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Primary full load current
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Ip−3ϕ=S3 ⋅VpI_{p -3\phi} = \frac {S } {\sqrt3 \: \cdot V_{p}  } \\Ip−3ϕ​=3​⋅Vp​S​
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Ip−1ϕ=SVpI_{p -1\phi} = \frac {S } {V_{p}  } \\Ip−1ϕ​=Vp​S​
Secondary full load current
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Is−3ϕ=S3⋅VsI_{s-3\phi} = \frac {S }{ \sqrt3 \cdot V_{s} }Is−3ϕ​=3​⋅Vs​S​
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Is−1ϕ=SVsI_{s-1\phi} = \frac {S}{V_{s}}Is−1ϕ​=Vs​S​
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Turns ratio
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n=VpVs=IsIpn = \frac {V_{p} }{V_{s}} =\frac {I_{s}}{I_{p}}n=Vs​Vp​​=Ip​Is​​
Where: 
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S=Rated power (VA)Vp=Primary voltage (V)Vs=Secondary voltage (V)S = Rated \: power \: (VA) \\ V_{p} = Primary \: voltage \: (V) \\ V_{s} = Secondary \: voltage \: (V) S=Ratedpower(VA)Vp​=Primaryvoltage(V)Vs​=Secondaryvoltage(V)
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