Answer / lalit barsker

vacuum circuit breaker is a device which is used to isolate
the faulty part of the power system from healthy part of the
power system & is used in switchgear.WHEN WE WANT TO SERVICE
OR MAINTEINANCE OF ANY SUBSTATION OR WANT TO CLEAR THE FAULT
DURING THAT CONDITION WE CAN ISOLATE THAT PART OF POWER
SYSTEM SO THAT WE CAN WORK IN THAT CONDITION ISOLATOR IS
OPEN AND SUPPLY CAN BE INTERRUPTED.

Answer / purushotham naidu.

Vaccum circuit breaker,as the name indicates is used to
break the circuit in faulty conditions and Arc quenching
medium is Vaccum. Isolator, as the name indicates isolates
the part of the system on occurence of fault without
actually being quenching/interrupting the arc....

Answer / mahesh m

The vaccum c.b are used to dissconnect the ckt when fault
accurse in the ckt,aswell as the vcb is used to break the
ckt in abnormall condition,in tn the name indicates the
isolators are used to isolates the ckt and the supply can
be intterupted by the mains.

Answer / ramakishore karri

the purpose of the vacuum circuit breaker is to isolate the fault system after the occurance of the fault. So that circuit breaker contacts open, in case of isolator it isolate the power for maintenance of the sub station as u like depends on us and it should not require any relay for finding the type of fault and interrupt the supply. In case of circuit breaker relay is required for finding the type of fault and it interrupt the circuit breaker.

HOW THE AC GENARATOR CAN GENARATE REACTIVE POWER,HOW CAN WE CONTROL IT.AND OTHER SOURSES OF REACTIVE POWER GENARATIONS ARE WHAT.

3 Answers  

---

At the time of 1st charging of transformer, there were huge inrush current, so why at that diffrential relay are not operated? Why?

3 Answers   Adani,

---

when i am going to take trail on a 3ph sq.i/m motor 5.5kw, i observed that RPM of the motor is very low as compared to the rated RPM and also it rotates in clockwise in first ON command,and anticlock wise in second ON command. finally i observed that on phase is no available . but iam not clear about, why the motor is rotates in both directions without any phase interchanging.pls answer to my question.

1 Answers  

---

What is the type of electrical motor used in mining industries?

2 Answers  

---

what is the operation of regulator in fan?

4 Answers   NTPC,

---

---

what is cathodic protaction?

0 Answers  

---

I am having dual speed motor of cromton greaves make of 3.7 KW -1400 rpm and 5 KW - 900 rpm. Please let me know groups and winding connction for rewinding purpose.

0 Answers  

---

what is potentiometer & rheostat

3 Answers  

---

diff. between star, delta connection?

4 Answers  

---

Who is the first Bangladeshi Everest climber? Where is his home district?

0 Answers  

---

Is there any particular formula for sizing the bus bar based on the current rating

1 Answers   Bunt Solar,

---

why the vfd motor take current high in vfd panel then mcc panel.current in vfd panel=160A in 93%.and mcc panel it shows 130A. (132kw motor)

1 Answers  

---