Transformer Calculator

Select the parameters and enter their values. The calculator will immediately calculate voltage, current value, and other transformer-related terms.

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I Want to Find:

Primary Voltage

VA ▾

Secondary Voltage

V ▾

Primary Winding:

Secondary Winding:

Secondary Current:

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Transformer?

A transformer operates to supply modern-day from one AC circuit to at least one or greater AC circuits. This factor works consistent with Faraday’s Law of Electromagnetic Induction to both step up or down the voltage.

formulation:

Voltage Equation:

\(V_p = N_p / N_s × V_s\)

Where:

\(V_p\) = Primary Coil Voltage
\(V_s\) = Secondary Coil Voltage
\(n_p\) = Number of Turns on Primary Coil
\(n_s\) = Number of Turns on Secondary Coil

equal cutting-edge Equation:

\(I_s=I_p*\dfrac{N_p}{N_s}\)

Load Currents:

Single-Phase:

\(Full-Load Current (Amps)= kVA × 1000 / V\)

Three-Phase:

\(Full-Load Current (Amps) = kVA × 1000 / (1.732 × V)\)

Turns Ratio:

\(Turns Ratio = N_1 / N_2 = V_1 / V_2 = I_2 / I_1\)

Transformer Amperage Chart:

Single Phase Transformers, Full Load Amperes (FLC):

KVA	120V	208V	240V	277V	480V	600V
.25	1.2	1.	0.9	0.5	0.4
.50	4.2	2.4	2.1	1.8	1.0	0.8
.75	6.3	3.6	3.1	2.7	1.6	1.3
1	8.3	4.8	4.2	3.6	2.1	1.7
1.5	12.5	7.2	6.2	5.4	3.1	2.5
2	16.7	9.6	8.3	7.2	4.2	3.3
3	25	14.4	12.5	10.8	6.2	5
5	41	24	20.8	18	10.4	8.3
7.5	62	36	31	27	15.6	12.5
10	83	48	41	36	20.8	16.7
15	125	72	62	54	31	25
25	206	120	104	90	52	41
37.5	312	180	156	135	76	62
50	416	240	208	180	104	83
75	625	340	312	270	156	125
100	833	480	416	361	208	166
167	1391	803	695	603	347	278

Three Phase Transformers, Full Load Amperes (FLC):

KVA	208V	240V	480V	600V
3	8.3	7.2	3.6	2.9
6	16.6	14.4	7.2	5.8
9	25	21.6	10.8	8.6
15	41.7	36.1	18.0	14.4
30	83.4	72.3	36.1	28.9
45	124	108	54.2	43.4
75	208	180	90	72
112.5	312	270	135	108
150	416	360	180	144
225	624	541	270	216
300	832	721	360	288
500	1387	1202	601	481
750	2084	1806	903	723
1000	2779	2408	1204	963