Table of Contents
Why the rating of A transformer is always in kVA?
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.
Are transformers rated in kVA?
The first reason is the power loss in the transformer. Thus, the total losses in a transformer depend upon volt-ampere (VA) only and not on the power factor of the load. That is why the transformer rating is given in kVA and not in kW.
Why transformers are rated in KVA or MVA?
The real reason is that all AC sources (transformer or alternators) are rated in VA (or KVA or MVA) is because the power factor of current is decided by the load connected. And since the load power factor is not known (while the transformer is being manufactured), they are rated considering resistive load (PF = 1).
Why are transformer rated in KVA and not kw?
The transformer does not alter the power factor of its output power. Transformers are rated in kVA because the losses occurring in the transformers are independent of power factor. KVA is the unit of apparent power. If the transformer is rated in KW, there may be confusions regarding the type of load being connected.
How much load can A 25 kVA transformer handle?
Three Phase Transformer
| KVA | 208V | 2400V |
|---|---|---|
| 20 | 56.6 | 4.82 |
| 25 | 69.5 | 6.02 |
| 30 | 83.4 | 7.23 |
| 37.5 | 104 | 9.03 |
Why transformers are rated in kVA or MVA?
Why motors are rated in kW not in kVA?
At the other hand, Motor has fixed Power factor, i.e. motor has defined power factor (p.f) and the rating has been mentioned in kW on Motor nameplate data table. That’s why we are rated Motor in kW or HP (kilowatts/ Horsepower) instead of kVA.
Why transformers are rated in KVA and not Watts or KW?
Transformers are rated in kVA because the losses occurring in the transformers are independent of power factor. KVA is the unit of apparent power. It is a combination of real power and reactive power. If the transformer is rated in KW, there may be confusions regarding the type of load being connected.
Why are alternators rated in kVA not in kW?
In alternator, Cu loss depends on current;iron loss depends on voltage. Hence total alterntor loss depends on volt-ampere (VA) and not on phase angle between voltage & current (load power factor). Hence, the rating of any electrical energy generating device is in kVA, and not in kW. Click to see full answer
How do you calculate kVA rating for transformer?
Calculate power rating in KVA when you know power in watts and the power factor. Use the formula: P (KVA) = P (watts)/pf where pf is the power factor of the power supply.
Why is DG set rating in kVA?
DG Sets are the Sources which provides power NOT CONSUMING the power,so KVA determines how much amount of power could be genertaed from a specific DG Set in short how much the DG set is capable of creating Amperes at certain voltage
Why is transformer rating defined in kVA?
Transformer does not produce any mechanical output.