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Three units of single phase transformers and one single three-phase transformer rating
will be same for one rating
can never be made same
may be same
none of the mentioned
will be same for one rating
A bank of three single-phase transformers and one three-phase transformer are functionally equivalent in terms of power rating and transformation ratio for a given load application. Both configurations are designed to handle the same total kVA rating while providing the same primary and secondary voltage levels.
A bank of three single-phase transformers and one three-phase transformer are functionally equivalent in terms of power rating and transformation ratio for a given load application. Both configurations are designed to handle the same total kVA rating while providing the same primary and secondary voltage levels.
S3╧ХтАЛ=3├ЧS1╧ХтАЛ тАФ Total power capacity of three single-phase units
VLтАЛ=3тАЛVphтАЛ тАФ Line voltage for Star connection
The total capacity of a three-phase system is S3╧ХтАЛ=3├ЧS1╧ХтАЛ. When three single-phase transformers are connected in a bank (e.g., Star-Delta), they simulate the operation of a single three-phase transformer unit. The internal magnetic coupling and physical arrangement differ, but the external electrical performance parameters remain identical for the same specified rating.
Three-phase transformers offer reduced floor space and lower weight compared to a bank of three single-phase transformers.
Single-phase transformers are easier to transport and replace individually in case of failure.
Electrical rating (kVA, Voltage, Frequency) is independent of whether the iron core is shared or separate.
Modular replacement for single-phase banks
Identical electrical characteristics for same rating
Three-phase units are difficult to repair on-site
Three-phase units lack redundancy compared to separate single-phase units
Distribution systems
Power grid transmission substations
| Feature | 3-Phase Unit | 1-Phase Bank |
|---|---|---|
Construction | One core/tank | Three separate units |
Option B is incorrect because physical configuration does not dictate the electrical rating capacity.
One three-phase transformer is essentially three single-phase windings on a common magnetic core.
A is correct тАФ The rating of a three-phase transformer is equivalent to a bank of three single-phase transformers of the same total capacity.
Always remember that for an ideal transformer bank or 3-phase unit, the efficiency and regulation are primarily defined by the winding resistance and leakage reactance, not the physical core structure.