VERTICAL BREAK ISOLATER

~ Porcelain has female contact on one post and mail contact on the other post.

~ Intermediate post insulator. 

~ Contacts can be opened and closed by

~  This formation is kind of center rotating double brake. 

~ It has three porcelain post insulators. 

~ A copper or aluminum rod is placed on the middle pole.  The middle pole can rotate 90 in the horizontal direction.  

~ There are female contacts on both the outside poles.

VERTICAL BREAK TYPE ISOLATER





HORIGENTAL BREAK ISOLATER



~ This type of isolator is used in Extra high voltage substations. 

~ It has one post insulator of porcelain line per pole.

~ A pantograph mechanism is mounted on it.  

~ There is a terminal above the post. 

~ Next to the insulator post is another insulator post that can be blown.  

~This post is operated by an operating mechanism.  

~ So with the help of pantograph the contact can go up and down.  

~ The arm of the pantograph comes in the vertical position in the close position of the pantograph.  

~ The upper two arms of the pantograph are connected to the overhead busbar.  

~ As a result current flows from the busbar to the lower terminal (busbar) via the Pantograph  link.  

~ The rotary insulator is rotated by an operating mechanism to open.  

~ With the link the pantograph's blade comes down and the connection opens.  

~ This type of isolator is used for Astra high voltage occupying less space.

~ This type of isolator can be placed in a convenient place and all three are not necessarily in the pole line.  I.e. the flexibility of mounting is obtained.


HORIGENTAL BREAK INSULATOR



SPACIFICATION OF ISOLATER

1) Rated voltage

2) Rated insulation level

3) Normal current rating

4) Short time current rating



INTER LOCKING BETWEEN ISOLATER AND CIRCUIT BREAKER 


~ It is not enough to simply open the circuit breaker for maintenance or repair. 

~ Because its contacts are connected to the busbar on one side, it is live.

~ This makes it necessary to isolate the circuit breaker.

~  An isolator is used for this. 

~ The isolator is attached to both sides of the circuit breaker. 

~  Opening the isolator after opening the cut breaker isolates the circuit breaker from both sides.  

~ Now isolators are designed to carry only rated current.

~ It is not designed to break currents.  

~ So if the isolator is opened before opening the circuit breaker, there is a big arc on its contact and fire starts. 

~ The operator is also injured. 

~  Hence the isolator before opening the circuit breaker Should not open. 

~ Similarly when the circuit is closed the isolator should be closed first and then the breaker should be closed.

~ If the earth switch is to be operated it should also be closed after the circuit breaker and isolator have opened it.

~  And when closing the circuit, first the earth switch should be opened, then the isolator should be closed and then the circuit breaker should be closed. 

~ Thus it is necessary to maintain the following log sequence to close the circuit breaker:

~ However, interlocking has been arranged to prevent the wrong operation even in case of error. 

~ The switch can be closed and the meaning is open only if the switch is open.