According to ohms law voltage proportional to current, then why should current rating is low with high voltage rating in transformer?

Answer Posted / p.anandsai

 If pressure (Voltage) increases,  current_________. 
if your answer is ” also Increases”.
Then why we say that P = V x I, and V = P/I,
in other words V = 1/I
How can you explain This ?
Actually, according to Ohm,s Law I= V/R, clearly Current is directly proportional to the Voltage, But according to P=VI or I=P/V, it shows that current is inversely proportional to the Voltage.




Now Lets me try to explain this statement. 




It depends on how you increase the voltage if you increase it by keeping the power of the source constant or not,,
if the power of the source is constant then the current would decrease when voltage increasing  ….if you don’t care about the power and just simply replace the battery with a new one’s with higher power rating this can increase the current.




in Transformer, when voltage increases then current decrease because power remains constant…both side power is P=VI




By Ohm’s Law, Current (I) is directly proportional to the Voltage (V) if Resistance (R) and Temperature remain same. 
I = V/R…..or…R=V/I…..or……V=IR.




According to P=VI…or…I=P/V….or …V=P/I,….. It says that Current inversely proportional to the voltage if power remain same.
as we know that in Transformer, If power remain same, and voltage increase, then current decreases in Step Up Transformer. also Voltage decreases when current increases as in Step Down Transformer.




Also on the generation side, same story will be there if power is constant.
but if we improve the power, then current and Voltage both will be increase. 




So Do Not Confuse about this statement.

Is This Answer Correct ?    1 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

If a rotary UPS is in line through grid power; What would be the impact on Power Factor if the load through rotary ups is 25% , 50% , 75% & 100%. Will the power factor reduce with less load?

1417


what is the id1 & id2 setting in differential protection relay of CSPC?

2283


What is the formula for calculating no-load current?

639


what is the difference between RMS & TRUE RMS VOLTAGE

2397


In how we connect watt meter for open & short circuit test of a single phase transformer.

5630






how to calculate the mesh earth network resistance in such substation, is there any recommended resistance values with references , thanks!

1834


what is the difference between STAR and DELTA connection and application wise how it can be utilizedd

1731


Haw to check conductivity of budbar

1337


What is steady state response?

670


What is the permissable nutral current of three phase system as per IS standards?

1523


what is doid

2298


In all analog voltmeters or ammeter showing some small size symbols. as well as a star and in star 2no. digit, resister symbol,and other. what is that's meaning ?

1575


Sir, plz tell me how droop setting is done in parellel operation od DG set ? please give practical example ?

1667


What are the types of the glands and difference between single and double compression type of cable Glands.

1614


what is the solution for meger test failed the MV cable?

3522