why current increases when voltage decreases in ac
system

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why current increases when voltage decreases in ac system..

Answer / ynrao

Power equals VI. to meet reqd. power if V reduces I has to
increase

Is This Answer Correct ?    51 Yes 7 No

why current increases when voltage decreases in ac system..

Answer / heamkumar

P=VI,
So V = P/I.

When P=100; I = 227A; then V=440v.

When P=100; I = 250A; then V=400v.

Is This Answer Correct ?    27 Yes 6 No

why current increases when voltage decreases in ac system..

Answer / muhammad ahmed

According to formula of P=VI.
P is the product of V and I thats why whenever one is
decrease another will increas.

Is This Answer Correct ?    19 Yes 6 No

why current increases when voltage decreases in ac system..

Answer / bowana

Ok well lets just back up a moment. what do you think
would happen if you applied 240v to a 120v motor (motor
wired only for 120v application). what everyone is saying
is the motor will only draw half the amps/maintain the same
wattage. Go ahead and try it. You might get a few seconds
out of the motor before it smokes. If motor windings
resistance stays constant, and you increase
voltage.....current goes up.
e over I/R (ohms law)

variables

volts (e) = 120
resis (r)= 10
NOW SOLVE FOR (I) "CURRENT"

120V DIVIDED BY 10 OHMS = 12 AMPS

240V DIVIDED BY 10 OHMS = 24 AMPS

smoke test 101

Is This Answer Correct ?    13 Yes 3 No

why current increases when voltage decreases in ac system..

Answer / eng.osama

because there is a reverse proportional between current and
voltage

Is This Answer Correct ?    22 Yes 15 No

why current increases when voltage decreases in ac system..

Answer / ashokreddy r

current increases when voltage decreases in any system at
the condition that KVA is constant

Is This Answer Correct ?    12 Yes 5 No

why current increases when voltage decreases in ac system..

Answer / puneet kumar

In our system, current is flow from source to load..and
source is defined in term of VA rating only.(for more
KVA,MVA..)
Thus VA of source is fixed.
It means V X A = Constant.
or V = Constant / A
or V is inversly proportional to A.
Therefore current increses when voltage decreases in ac
system.

Is This Answer Correct ?    8 Yes 3 No

why current increases when voltage decreases in ac system..

Answer / pankaj

transformation ration k = n1/n2=v1/v2=i2/i1.
or k = v1/v2 = i2/i1 which is inversly proportional

Is This Answer Correct ?    6 Yes 6 No

why current increases when voltage decreases in ac system..

Answer / ashish rai

First of all of you notice that p=vi* cos(phi)
Another thing is that for running ac system 10% of voltage
fluctuation is allowed from electricity board.

Hence V is nearly constant factor.
I*cos(phi) is the variable factor hence with variation in
current power factor of system will change not voltage.

If any body is making wrong it plz clarify it.

Is This Answer Correct ?    6 Yes 6 No

why current increases when voltage decreases in ac system..

Answer / mostafa

P=VI,
So V = P/I.

When P=100; I = 227A; then V=440v.

When P=100; I = 250A; then V=400v.


in the above expamle, if the loads were to calculate (load1
= 440/227, and load2 = 400/250). Therefore, load1 is
different than load2. is this possible with the same
equipment?

Is This Answer Correct ?    3 Yes 4 No

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