what is different between buchhoz relay and pressure relife devices in transformer

2 Answers   Spanco,

---

This is about the recent problem that we have faced in our project site. We have 6/7.5 MVA. 66/11kV three phase star - star power transformer. The neutral was solidly connected to the earthing mat. But because of high resistance of earthing mat (130 ohm on LV and 180 ohm on HV), one day LV side neutral earthing conductor melted and we had a huge damage. Can any one plz tell me what might happen when we connect power transformer neutral to the earthing mat which has high resistance (>100 ohm ) ?????

2 Answers  

---

How to calculate the lighting load & power load requirement by knowing area of building/room. Is there any thumb rule?

3 Answers  

---

what will happen reduce the transformer voltage from 415v to 406v, is it save the energy,? are this methodis good to reduce the energy.?

0 Answers  

---

why we use taping of transformer on HT side?

4 Answers  

---

---

why test lamp didn't glow across 500v megger?

4 Answers   Aurobindo,

---

what irequirment need to be followed when working on live equipment

0 Answers  

---

what is power factor

5 Answers   Exide,

---

Why is transformer core is earthed

3 Answers  

---

why r use the wave taper in the substation ?

2 Answers   L&T,

---

you have a 2 tonne ac that operates for 2 hrs daily what will be you monthly bill (this is complete question asked nothing else was given)?

1 Answers  

---

We have one Energy meter for Measuring the voltage,current,power,energy(KWH,KVARH,KVAH) & power factor.The problem is that the meter does not show whether the PF is lagging or leading.So i want to know that is there any way or calculation to find out that whether the PF sign (lagging or leading) depending upon the above mentioned parameters?

4 Answers  

---