Answer / searchvineet

every measuring type or protection special current
transformer comes with a ratio of there Ip/Is [Ip=current in
primary Is means current in the secondary] which generally
means how much minimum current you are injecting in the
primary and with respect to that how much you are getting on
the secondary.Lets say 100/1 means 1amps in secandry for
flow of 100 amps in primary.
know lets say if u inject more then 100 amps in the same CT
say 200amps what will happen??????
So the Answer for understanding the Knee point is above .
There is a level of sustaining in the CT up to which it will
work perfectly fine beyond that limit or after that limit it
will behave abnormally and there is a point came after which
it Will SATURATE that level is called as the knee point

Answer / sonu pal

That sinusoidal voltage of rated frequency applied to the secondary terminals of the CT, which when increase by 10 %, cause the exciting current to increase by 50%.

Knee point voltage, V= K.Is (Rct+Rb)
K= is a parameter to be specified by customer which depends on the system fault,
Is= secondry current
Rct= secondry winding resistance at 75 deg C
Rb= impedance of secondry circuit.

we have one pumping station and 4.6 MW 7 no.s synchronous motors.so there is no required HT capacitor to improve power factor.But we have two no.s of 25 Mva power transformer connect to distribute the power for motors connect with 220 kv line.So i have required the HT capacitor to improve power factor at HT side i mean power transformer bus side.So please suggest how much HT capacitor banks required for same.

1 Answers  

---

how actually an anti pumping device works? what is the operational principal?

2 Answers  

---

How is the gain affected by the introduction of feedback in a control system.

0 Answers   GE,

---

how to generator maintenance (A Check, B check,Etc)

0 Answers   Cummins, HCL,

---

In scott connected transformer number of turns in the primary winding of teaser transformer is % of number of primary turns of main transformer A 86.6 B 57.7 C 14.4 D 33.3

1 Answers  

---

What are the criteria shall be considers for sizing Fuse and MCB? If the rated current is 10Amps what should be the fuse size / MCB Size?

0 Answers  

---

Is it possible to use a S1 duty class motor for crane application (S4)? If not, why?

0 Answers  

---

phase clearance between phase to phase and earth

11 Answers  

---

Explain about p.t?

0 Answers  

---

what is the power factor

13 Answers   Heidelberge Cement,

---

Hot Water System (HWS). Will a 30ma elcb have more nuisance tripping than 100ma elcb

1 Answers   CIMC,

---

I need a formula to calculate the size of cable as per load but in the terms of length. Please Reply me as i search lot of sites but i did not get the answer.

0 Answers  

---