Interested to Buy Any Domain ? << Click Here >> for more details...
what is the frequency of direct current(dc)?
- 12 Answers
- 38280 Views
- Cognizant, University, I also Faced
- E-Mail Answers
Answer Posted / amina
Frequency,as regards voltage, is the term applied to changes in voltage per unit time.As the voltage in DC does not changes,as it changes in AC periodically. Hence, DC has zero Hurtz frequency....
| Is This Answer Correct ? | 2 Yes | 0 No |
Post New Answer View All Answers
A 15 kw squirrel cage motor having a maximum efficiency of 90% on a continuous full load has temperature rise of 42 degrees celcius after 30 min and 52 degrees celcius after 1 hr under the above operation conditions. a) calculate its final steady state temperature rise on continuous load and the heating time constatnt. b) if the motor is operated on a short load for 9 min estimate its temperature rise. c) calculate the maximum overload that can be applied on a short, 9 min rating so that the temperature rise is the same as the final steady state temperature rise on continuous load.
Draw the vector diagramme for Asynchronous Induction Generator at noload,half load and fullload.
What is the operating principle of turbo-generator.
What are the basic component of a cro?
Sate maximum power transfer theorem?
What are chief characteristics of state-space method and its techniques ?
What are unstable systems?
what is the difference between STAR and DELTA connection and application wise how it can be utilizedd
How to determine alternating current frequency?
What is the exact formula for one weber of magnetic flux?
how to select correct size of power cable for inverter duty motor
What is the accepted limit to increase the choosen transformer capacity over the load and why ?
How to design the no. of ceiling fans required in 5mtr X 10 mtr X 3 Mtr hight room?
What is the need of earthing transformer for delta side of a transformer. (Think of a line section between a star/delta transformer at a grid substation and delta/star transformer at a village. An earthing transformer is there at the delta side of the star/delta transformer at grid substation). As there are no ground reference there will not be fault current if a one phase is grounded. Further L-L phase will be sensed by the primary side of star/delta transformer as a L-G fault. So why an earthing transformer is required at delta side
please write motor, transformer, Generator setting, fault level calculation of Tr.etc
