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## How do you determine the maximum amps of a transformer?

The full load current I_{(}_{A}_{)} in amps is equal to **1000 times of transformer rating S _{(}_{kVA}_{)}** in kVA divided by the multiplication of root 3 times of line to line voltage V

_{(}

_{V}

_{)}in volts.

## How many amps can a 15 kVA transformer handle?

Primary = (20 x 1000) / 480 = 20,000 / 480 = **41.6 amps**. Note: for a three-phase transformer, the formula is Primary = KVA x 1000 / (Vprimary x 1.732).

## How do you calculate the full load current of a transformer?

**Transformer full load current = kVA / (1.732 x Volt)**

- Transformer full load current = kVA / (1.732 x Volt)
- Transformer full load current = 1000 / (1.73 2× 480) = 1203 Amp.
- Short circuit current at TC secondary (Isc) = Transformer full load current / Impedance.

## What is the transformer formula?

**Vp=−NpΔΦΔt V p = − N p Δ Φ Δ t** . This is known as the transformer equation, and it simply states that the ratio of the secondary to primary voltages in a transformer equals the ratio of the number of loops in their coils.

## How do you calculate the power rating of a transformer?

Use the formula: **P(KVA) = (V^2/R)/1000 where R is resistance in ohms**. For example, if V is 120 volts and R is 50 ohms, P(KVA) = V^2/R/1000 = (14400/50)/1000 = 288/1000 = 0.288 KVA. Calculate power rating in KVA when you know power in watts and the power factor.

## How many amps will a 25 kVA transformer handle?

Three Phase Transformer

KVA | 208V | 480V |
---|---|---|

20 | 56.6 | 24.1 |

25 | 69.5 |
30.1 |

30 | 83.4 | 36.1 |

37.5 | 104 | 45.2 |

## How many amps does a transformer draw?

For a 120-volt primary, 2000-watt transformer, divide 2000 by 120 for the current (2000 Watts /120 volts =16.67 amps). For a 240-volt, 3000-watt transformer, the current is **12.5 amps**.