Answer / pradyumna chandra panda

By help of power trangle pf= value of cos thita (cos fi)=
b/h=active power/apparent power. Active power (kw)is the
real or true power which the transformer give for a
aparticular load (useed power)and Apparent power(kva)is the
supply power for that particular load. That a 100 kva
transformer can supply/give 100 kw resistive load and
incase inductive circuit a 100 kva rtransformer give 80 kw
inductive loadat at.8 pf,and 75 kw inductive load at.75 pf
etc but the pf of the load is not known before that which
types load (resistive,inductive or capacitive)to be
connected across the suplly, this is only why the
transformers and Alternaters are rated in kva and it is
meaningless discuss about iron loss & copper loss because
the UPS and inventers are also rated in kva.

Answer / praphulla bansal

KVA is mentioned to take care of PF issues of the load. At the same time, rating of transformer is given a limiting PF. This means a 100 KVA transformer and limit of 0.8 PF will limit load to 80 KW irrespective of load PF as unity.

Answer / md. abdullah al mamun

I think Copper loss of a transformer is related to current
and core losses are related to voltage so that VA should be
the rating of a transformer. But in a large transformer it
is rated it KVA. Also KVA rating Indicate the Maximum
Current Rating of a transformer with a rated voltage.

A 1F capacitor is charged to 100V initially. A 1H inductor is connected accros the capacitor througha a switch. The current in the circiut when the switch is closed is____

0 Answers   Ecil, L&T,

---

What is the maximum operating temperature for a thermoplastic insulated cable?

0 Answers  

---

how many stairs have you climbed while you were coming

0 Answers   Bhel, SSB,

---

i want all question & answers of the written exam

1 Answers   Essar, L&T, MES, RRB,

---

What is OT in a transformer, specify its function.

2 Answers  

---

Why earthing is required for diesel tank?

4 Answers   Greaves,

---

it is difficult to interrupt a capacitive current because (a)it has a leading power factor (b)current magnitude is very small (c)the restriking voltage can be high (d)stored energy in the capacitor is high

2 Answers   DGVCL Dakshin Gujarat Vij Company, MGVCL, UGVCL Uttar Gujarat Vij Company Ltd,

---

In transmission line 11kv,33kv etc are rms values are peak or others??

1 Answers  

---

whether the battery is voltage source or current source?

2 Answers  

---

what is the size of cable for 15kw motor and 85 meter cable length using with vfd

0 Answers  

---

carbon zinc cell voltage?

3 Answers  

---

is ac supply can store

0 Answers  

---