Answer / amit shankar choudhary

Tan Delta, also called Loss Angle or Dissipation Factor
testing, is a diagnostic method of testing
cables to determine the quality of the cable insulation.
This is done to try to predict the
remaining life expectancy and in order to prioritize cable
replacement and/or injection. It is also
useful for determining what other tests may be worthwhile.
How Does It Work?
If the insulation of a cable is free from defects, like
water trees, electrical trees, moisture and air
pockets, etc., the cable approaches the properties of a
perfect capacitor. It is very similar to a
parallel plate capacitor with the conductor and the neutral
being the two plates separated by the
insulation material.
In a perfect capacitor, the voltage and current are phase
shifted 90 degrees and the current
through the insulation is capacitive. If there are
impurities in the insulation, like those mentioned
above, the resistance of the insulation decreases, resulting
in an increase in resistive current
through the insulation. It is no longer a perfect capacitor.
The current and voltage will no longer
be shifted 90 degrees. It will be something less than 90
degrees. The extent to which the phase
shift is less than 90 degrees is indicative of the level of
insulation contamination, hence
quality/reliability. This “Loss Angle” is measured and analyzed.

Answer / wareagle

Its tan delta. Not ten delta. You can google that for
yourself.

what will happen when reverse reactive power occurs in alternators?

3 Answers   Reliance,

---

What is system earthing?what are the types?

1 Answers   ABB,

---

why r we using shell transformer for low voltage

0 Answers  

---

what are all the preventive maintainance carried out in DG?

1 Answers   TATA,

---

A IS TWICE AS GOOD A WORKMAN AS B AND TOGETHER THEY FINISH A PIECE OF WORK IN 14 DAYS.THE NUMBER OF DAYS TAKEN BY A ALONE TO FINISH THE WORK IS 1.11 2.21 3.28 4.42

3 Answers   Ramky,

---

why do MCB melt but not tripped in lighting highmast??

1 Answers   AHPCL,

---

why the conservater tank alwes made upper side of transformer???

3 Answers  

---

Can you please explain creepage distance in detail, for a 6.6kV cable head what must the distance be and how do you determine it?

0 Answers   Prism Cement,

---

What happen if in three phase 440 v , when you check voltage by testor it glows except one phase and in the same time when you check by multimeter it shows 440 v in any two phase.what will be the reason...

1 Answers   Greatship,

---

If you have an earth with pilecap then your resistance is really low. why and how?

0 Answers  

---

Why single phase induction motors are not self starting ?

0 Answers  

---

what is voltage gradient?

8 Answers   Bhel,

---