Electrical Engineering - Transformers - Discussion
Discussion Forum : Transformers - General Questions (Q.No. 1)
1.
What kVA rating is required for a transformer that must handle a maximum load current of 8 A with a secondary voltage of 2 kV?
Discussion:
121 comments Page 2 of 13.
SANTHOSH said:
1 decade ago
p=vicosQ for single phase p= root3*VICosQ for three phase
Consider 0.95 PF For transformer
0.80 PF for generator
p=2000*8*0.95
= 15200=15.2KW
so PF = KW/KVA we need KVA rating
KVA= KW/PF
= 15.2/0.95=16KVA.
Consider 0.95 PF For transformer
0.80 PF for generator
p=2000*8*0.95
= 15200=15.2KW
so PF = KW/KVA we need KVA rating
KVA= KW/PF
= 15.2/0.95=16KVA.
Charu said:
1 decade ago
In transformer copper loss is depends on current ( I^2 R ) and core loss is depends on voltage, so only the rating of transformer is expressed in KVA.
So KVA = secondary current x secondary voltage.
KVA = 8 x 2.
KVA = 16 KVA.
So KVA = secondary current x secondary voltage.
KVA = 8 x 2.
KVA = 16 KVA.
Kedar apkar said:
1 decade ago
p=vicosQ for single phase p= root3*VICosQ for three phase
Consider 0.95 PF For transformer
0.80 PF for generator
p=2000*8*0.95
= 15200=15.2KW
So PF = KW/KVA we need KVA rating
KVA= KW/PF
= 15.2/0.95=16KVA.
Consider 0.95 PF For transformer
0.80 PF for generator
p=2000*8*0.95
= 15200=15.2KW
So PF = KW/KVA we need KVA rating
KVA= KW/PF
= 15.2/0.95=16KVA.
Kiran said:
1 decade ago
Pf = True power/Apparent power.
Pf = Kw/Kva.
Kva = Kw/Pf.
P = v*i*cos Q = True power.
Pf for transformer is 0.95.
So P = 2000*8*0.95.
P = 15200 = kw.
Kva = 15200/0.95 = 16000 VA.
Kva = 16 KVA.
Pf = Kw/Kva.
Kva = Kw/Pf.
P = v*i*cos Q = True power.
Pf for transformer is 0.95.
So P = 2000*8*0.95.
P = 15200 = kw.
Kva = 15200/0.95 = 16000 VA.
Kva = 16 KVA.
Vimal said:
1 decade ago
Mr madhusudhan.
By saying same voltage across the current & voltage in primary &secondary winding. Then, how could we step up &step down voltage of an transformer by using this concept?
By saying same voltage across the current & voltage in primary &secondary winding. Then, how could we step up &step down voltage of an transformer by using this concept?
Sudhandiran K said:
1 decade ago
Actually we know the formula as
E2/E1=N2/N1=I1/I2
From this we have to consider
E2/E1= I1/I2
The secondary voltage is given ,so E2*I2=E1*I1
E1*I1=2Kv *8A
=16 KVA
Am I right
E2/E1=N2/N1=I1/I2
From this we have to consider
E2/E1= I1/I2
The secondary voltage is given ,so E2*I2=E1*I1
E1*I1=2Kv *8A
=16 KVA
Am I right
Vijay said:
1 decade ago
Well question itself gives us the secondary voltage as well as load current i.e.,secondary current and we know that kva=current*voltage (either primary or secondary).
2kva*8A = 16kva.
2kva*8A = 16kva.
BELAL MOMIN said:
10 years ago
Because in short circuit test current flow through low resistance path & maximum amount of current flow this sc path that's why iron loss is negligible as compare with copper loss.
JOGI said:
1 decade ago
KVA = V * A/1000
The rating of transformer is Kilo Volt Ampere . So that it is dvided by 1000. 2KV= 2*1000=2000 SO . 2000*8=16000/1000=16KVA . This is the ans for above problem
The rating of transformer is Kilo Volt Ampere . So that it is dvided by 1000. 2KV= 2*1000=2000 SO . 2000*8=16000/1000=16KVA . This is the ans for above problem
Murali said:
1 decade ago
The output rating of transformer in KVA=v*i
=2000*8
=16000
=16KVA
=2000*8
=16000
=16KVA
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