**Contents**show

## Why transformer ratings are usually expressed in terms of?

Transformer voltage comes into play in iron losses and the current is used to calculate copper losses. Thus the transformer ratings consist of both voltage and current and thus the ratings are expressed in **kVA**.

## Why is rating of transformer expressed in kVA?

**The copper and iron are the two types of losses that occur in the transformer**. The copper loss depends on the current (ampere) flows through the windings of the transformer while the iron loss depends on the voltage (volts). i.e., the rating of the transformer is in kVA.

## How do you write a transformer rating?

**How to Calculate the Rating of Transformer**

- The rating of transformer is given in terms of its kVA, HV/LV voltage and phase rotation (for three phase transformer). …
- Suppose the load requirement of a utility to be fed is 85 kW, then the kVA rating of transformer should be (85/0.85 = 100).

## What is the average EMF per turn in a transformer?

This rate of change of flux per turn is the induced emf in V. Therefore, average emf/turn = **4fΦ _{m}m V**.

## How do you find the kVA 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.

## How do you calculate kVA rating?

In many cases, it’s useful to convert kVA to amps. S stands for apparent power; the very thing that is measured is Volt-Amperes (VA).

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kVA To Amps Calculator (With Table)

kVA (Apparent Power) | Voltage (220 V) | Amperage (A) |
---|---|---|

How many amps is 1 kVA? | 220 V | 4.55 Amps |

How many amps is 5 kVA? | 220 V | 22.73 Amps |