Answer / nithi

NO.We can't sense the over voltage by just measuring the
current only.because,
The current increases not only for over voltages but
also for under voltage(As most of the loads are non-linear
in nature).
So,the over voltage protection & over current
protection are completely different.

over voltage relay meant for sensing over voltages &
protect the system from insulation break down and firing.

over current relay meant for sensing any internal
short circuit,over load condition ,earth fault thereby
reducing the system failure & risk of fire.

So, for a better protection of the system,It should have
both over voltage & over current relay.

Why lightning arrester blast in rainy day?

1 Answers   Eco Cement, Mahaveer, MBDL,

---

why we are using auto transformer in sub station mostly???

2 Answers  

---

how to mention 5mw generator in kva ? gen voltage is 11kv

6 Answers  

---

I am doing apprenticeship training at HT switch yard in NLC. How can i get electrical c license. ??? What r the rules for getting it as an apprentice? ??

0 Answers  

---

what is role of mpu in dg

1 Answers  

---

What is servo motor and what are different types of servo motor

0 Answers   BARC, Vipul,

---

What is inductance?

0 Answers  

---

A.V.R maintains the voltage of a generator when it is in island mode but when the generator is synchronised with grid it maintenance the P.F,how it happens please any body explain it in detail.

2 Answers   TATA,

---

what are the advantages and disadvantages of oil filled cables over XLPE cables

3 Answers   Areva, AUVA,

---

what is frequency transformer?

2 Answers  

---

at which places we use 6.6KV Transformers and Motors

4 Answers  

---

What is effect of low pf on HT supply.

6 Answers  

---