In DC while we mention the voltage we are using -48V but in
case of AC we mention only 230V not -230V, why we using -48V
not 48V
Answer Posted / cnu
in the measurement of voltage in any circuit we measure the
voltage of one conductor with respect to another.
In DC supply we have two conductors namely Positive(+) and
negative(-). if we consider 48V DC across the two
conductors, then if we measure the value on the positive
conductor with respect teo the negative conductor the value
is +48V. if we measure the same value on the negative
conductor with respect to the positive conductor then the
value will be -48V. this 48V is the instantaneous value of
the DC supply.
Where as in AC we have two conductors namely Phase and the
Neutral. always the Phase constitute the current path and
the neutral forms the return path. we say that the AC
voltage is sinusoidal. that is it varies from positive to
negative when seen with respect to the neutral.
its impossible to measure the instantaneous value of the AC
supply bcoz it keeps on continuosly varying. so for the AC
supply we consider the RMS value (Root Mean Square Value)
as the voltage of the supply. so in this case there is
always the same value when measured with respect to any
conductor. so the AC voltage does not have polarity.
| Is This Answer Correct ? | 10 Yes | 0 No |
Post New Answer View All Answers
Capacitor is load free component but why ampere meter shows current when capacitor bank breaker close?
As you achieve greater success with the company after some years, Will you like to be a share holder in our company?
We are designer please help me calculate the size of 11kv cables from step up transformer to M.V panel, total load is 5 mega watt distance 900 feet (used aluminum type cables) please provided formula for calculate the cable with example.
What is inverse definite minimum time lag relay? Where is it use?
What is ST and specify its range of voltage.
A TRANSFORMER 440/400V,DELTA/STAR CONNECTED.THE NEUTRAL CONNECTED WITH GROUND CABLE THAT IS DIRECTLY CONNECTED TO THE PANEL,FROM PANEL IT IS CONNECTED EARTH PIT.IS IT RIGHT? IF IT IS RIGHT LEAKAGE CURRENT AFFECTED.SECONDATY IS PROTECTED WITH EARTH LEAKAGE RELAY.
is it true there's a big difference in using Cummins or Denyo...especially power output or leakage
hi frds, i m electrical engineer.can i get cdr for electrical engineer if u have then send me on my mail id its jayesh_ee88@yahoo.com.please help me frds
If we have to find the inductance of a dc shunt motor then by giving dc supply or ac supply and what is the reason for it. (this example is from "to determine the transfer function of a dc shunt motor ")
what is meant by 2 within a star in a voltmeter dial?
please send the IS strandard for electrical to sakthi_murugan86@yahoo.co.in
How 48-relay (incomplete sequence) functions?
How you will determine the volume of oil in a particular Distribution transformer.
What is true sine wave or pure sine wave inverter?? Is it sine wave or step wave?? If it is step wave, waves with how much step is considered as pure sine wave? Is it possible to produce pure sinewave using power electronics?
Comparision of Air break circuit breaker, SF6 Circuit breaker and vacuum circuit breaker.