we see that the rating which entering our house is 415 volt but the rating is originally inur house 230 volt?

Question

why is the diifference of 415 & 230 volt????

Answer 1

In electrical transmission and distribution system, (assuming that u r a resident of India) the electrical supply from your local sub-station is 11 KV (Kilo Volts) phase to phase. You will see three wires comming from the sub-station to ur local transformer.

The local transformer is a three phase step down transformer. Primary winding is connected in delta to the incomming 11KV and secondary winding is connected in star. The secondary voltage is generally 415V phase to phase.

The centre point of the star connection is earthed at the transformer end. From the same point another wire is taken which is designated as Neutral. Hence we get four terminals at the output of the transformer as R, Y, B and N.

If we measure the voltage between N and any phase (R, Y or B), we will get 230 Volts. If we measure the voltage between phase to phase (R-Y, Y-B or R-B) we get 415 Volts.

In short, phase to phase voltage is 415 Volts and Neutral to Phase Voltage is 230V.

Answer 2

In US there's no 415 Vac supply to residences, unless they had three phase power and the voltage input should be 480 Vac not 415 Vac. For three phase 480 Vac there should be a step down transformer to lower voltage for house appliances.

Answer 3

Ur qstn needs clarification, 415VAC is 3 phase supply and 230 VAC is single phase supply, i did not understood the meaning 415 rating is entering

Answer 4

Im not sure what you are asking but the voltage varies from country to country.