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Question
I have a transformer whose primary operates at 230V, 50Hz 
for which the secondary voltage will be 12V, 50Hz. What 
will be the secondary voltage if the primary is fed with 
400V, 8KHZ Signal?
 Question Submitted By :: Ganesh.m
I also faced this Question!!     Rank Answer Posted By  
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 1
20.869v,8kHz  is the voltage and frequency of secondary.
 
Is This Answer Correct ?    2 Yes 3 No
Shyamkr
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 2
Assume that the transformer is typical iron-cored stepdown 
transformer.
The actual output result will not be 20.86 volts calculated 
with straight ratio and the transformer will likely be 
destroyed due to the following factors:
1. Iron core has lower frequency response and that makes it 
good only for 50-60Hz.  8,000Hz frequency will not get 
transformed properly because the magnetic flux in iron core 
will be saturated.  The primary coil will receive 
equivalent to direct current voltage therefore is likely to 
overheat.
2. The insulation of a 230v transformer will not withstand 
400v therefore ground leakage is very likely.
3. The size of copper wire and number of winding suitable 
for the current rating designed for 230v will draw more 
power into the coil when connected to 400v, again, 
overheated.
 
Is This Answer Correct ?    14 Yes 0 No
Pised
 
 
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 3
o/p voltage will be 20.8 volt, but due to very high 
freguency 8 Khz hytresis loss & edd current will be 
increased because this loss is directly related to 
frequency.
 
Is This Answer Correct ?    2 Yes 2 No
Prashant
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 4
20.86v.8khz
 
Is This Answer Correct ?    0 Yes 2 No
Satya
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 5
e1/e2=e3/e4
230/12=400/e4
e4=400/19.16667
e4=20.869v
so ans is : 20.869v
freq remain same.
 
Is This Answer Correct ?    2 Yes 2 No
Raj(b.e.electrical)
 
  Re: I have a transformer whose primary operates at 230V, 50Hz for which the secondary voltage will be 12V, 50Hz. What will be the secondary voltage if the primary is fed with 400V, 8KHZ Signal?
Answer
# 6
3/23volts or appro .13 volts. assume xmer to be ideal one 
with no resistance in windings,nohysteresis loss etc, at 
80khz the frequency is 160 times 50khz ,so current in 
primary is 160 times less than at 50hz as inductive 
reactance of primary ,ie 2 pi f l is 160 times more. as 
current is 160 times less so is magneti flux in core,and so 
is induced emf in secondary. if hysteresis loss and eddy 
current loss r considered , then it is even less
 
Is This Answer Correct ?    2 Yes 0 No
Anshul Rawal
 

 
 
 
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