The maximum efficiency condition in distribution transformer is said to be occurred when
iron loss = copper loss
It is always desirable to run any equipment or device at maximum efficiency for that matter, not only the power transformer. Power transformer maximum efficiency occurs when copper loss is equal to iron loss. (or no load loss equals to load loss). This does not necessariliy mean that maximum efficiency occurs at maximum or full load. Generally the maximum efficiency occurs at relatively less than full load of the transformer.
the efficiency is maximum in a transformer when no load loss is equal to load loss.
100MVA
That is the maximum efficiency occurs when the copper losses are equal to the core losses of the transformer.
The efficiency of a simple transformer is limited by resistive loss in the wiring, and by hysteresis (magnet related) losses in the transformer core. You may limit the resistance loss by using superconductors at very low temperatures. But not practical for most situations. (Yet!)
The transformer will have the maximum efficiency.
The condition for maximum efficiency of a d.c. machine is that VARIABLE LOSSES must be equal to CONSTANT LOSSES i.e., variable losses = constant losses..
there are several losses in a transformer that prevent it from attaining 100% efficiency. One is core loss, which can be divided into Hysteresis losses, Eddy currents and Magnetostriction loses. see for more details http://en.wikipedia.org/wiki/Transformer#Energy_losses
An electricity board will be fixed some amount of load for consumer (industry or commercial) as per consumers requirement.That is maximum load or maximum demandAnswerA 'maximum demand indicator' (also called a 'thermal demand indicator') is a thermally-operated measuring instrument which indicates the maximum current supplied by a distribution transformer, from which that transformer's actual (rather than anticipated) maximum load can be determined. A distribution transformer is sized based on an anticipated load, resulting from an analysis of the loads to be supplied (taking into account after-diversity maximum demand), this instrument allows the actual maximum load to be compared with that calculated load, and this value should be less if the original analysis was performed correctly.
It depends on the load. A good transformer has over 90% (some as high as 99%) efficiency. So the power drawn by it is a function of the power in the load, plus a small amount due to losses in the transformer.
Maximum efficiency of a power transformer occurs when copper loss equals to iron losses. Decrease in current does not result in increase in efficiency unless the copper loss was more than iron loss and the decreased current made the copper loss is reduced and became equal to iron loss at some point.
Copper losses are directly related to loading of the transformer. Iron (core) losses are a result of magnetizing of the core of the transformer, and are relatively constant from no load to full load. With this in mind, it should be clear that the above statement is false. Maximum efficiency results with low core losses, and low copper losses. Copper losses cannot be helped, so it is important to minimize core losses to increase the efficiency of a transformer.AnswerYes, it is perfectly correct -well, with the proviso that transformers normally operate somewhat below full load and, so, are designed to achieve maximum efficiency somewhat below full load. A transformer's maximum efficiency does indeed occur when the copper losses and iron losses are equal. Unfortunately, the mathematical proof of this is too complicated to reproduce here, I suggest that you check out any reputable electrical engineering textbook.