# Why transformer rating is expressed in kVA or VA?

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## Why transformer rating is VA or 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.

## Why transformers are rated in kVA and motor in KW?

Transformers have copper losses and iron losses. Copper loss depends on current and iron loss depends on voltage. … All AC devices that supply power, such as transformers, UPS, generators, etc are rated in kVA. Devices that consume power, have a kilowatt rating, because we know what its power factor is.

## What is VA rating in transformer?

The VA rating refers to the power distribution rating relative to how much power the transformer can deliver to the load. To calculate VA, you need to know the supply voltage and the current delivered to the load.

## Why OC test is performed in a transformer?

The purpose of the open-circuit test is to determine the no-load current and losses of the transformer because of which their no-load parameters are determined. This test is performed on the primary winding of the transformer. The wattmeter, ammeter and the voltage are connected to their primary winding.

## What is the SI unit of transformer?

This alternating flux creates an alternating electromotive force (emf) in the transformer’s secondary coil. This phenomenon is called mutual induction. The SI unit name for electromotive force is volt and its symbol is V.

## Why do we use kVA instead of kW?

kW is the amount of ‘actual power’ an electrical system has. This shows you how much power is being converted into useful, working output. kVA, on the other hand is the measure of ‘apparent’ power. If kW is how much power you can work with, kVA tells you how much is being used in the system overall.

## 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.

## What is VA rating?

A VA Disability Rating is a percentage assigned by the VA to a veteran’s service-connected conditions. The ratings are meant to reflect the severity of the conditions. The higher the rating percentage, the more compensation the veteran receives for the condition.

## How do you convert kVA to VA?

Kilovolt-amps can be expressed as kVA and volt-amps are expressed as VA. Use the following formula to convert kVA to VA. There are 1,000 VA in 1 kVA, so to VA is equal to kVA times 1,000. For example, convert 5 kVA to VA.