Skip to main content

elcb and rccb

                                    ELCB AND RCCB

ELCB : (EARTH LEAKAGE CIRCUIT BREAKER) 


        The ELCB, which normally operates based on voltage, is a simple ELCB.  The way the Voltage ELCB works is simple.  A terminal of the Relay coil is attached to the metal body of the equipment to be protected.  Next to Relay Coil. If any insulation fails, or the phase wire in the electric supply touches the metal body of the equipment, a voltage difference occurs between the relay coil connected to the equipment and the earth.  When this voltage difference exceeds a certain limit, the relay coil becomes larger and the relay becomes operable.  So the circuit breaker attached to the relay operates and disconnects the supply to the equipment.

RCCB : (RESIDUAL CURRENT CIRCUIT BREAKER) 


        Residual current circuit breaker is more sensitive than ELCB.  The ELCB, based on the current, is called the RCCB. it contain 2 primary windings and 1 secondary winding which is connected to relay . The phase and neutral residual flux are normal in the normal condition.  The resultant flux caused by these two co-efficients is zero, since both are equal and opposite.  So no passes through the secondary winding of the CT.  Thus the relay attached to the secondary winding of the CT will not operate.

        In the event of a earth leakage current in the instrument, the partial current of the phaser span passes through the leakage path to the earth instead of the neutral. now the resudual flux in upper primary winding and lower primary winding will become unequal to the phase current.  So a resullant flux occurs in the core of the CT.  This causes a current flow  in the secondary of the CT.  So the relay operate connected to the secondary of the CT and trip the circuit breaker.  

TEST CIRCUIT :

        To test the RCCB, a test tag is attached.  This test circuit is on the load side with the line conductor and the supply side.   The current goes through the test circuit.  The size of this current depends on the resistance that is set in the circuit.  The current passes through the phase side coil along with the load current. That is, bypass.  Therefore the current passing through the RCCB's phase side and the neutral side is not equal.  So RCCB trips the supply even at normal.

mp3
                       CLICK My LOGO TO DOWNLOAD MP3

                                                    OR

    
        VIDEO LINK: https://youtu.be/D5qJ7Toknb4



T     H      A      N        K             Y        O        U           B       Y    :

                                          R      D      K
                                                   &
                             T            E             A             M

Comments

Post a Comment

Popular posts from this blog

LAYOUT OF 110/11KV SUBSTATION

                   LAYOUT OF 110/11KV SUBSTATION: CIRCUIT DIAGRAM: THEORY : 1. The 3 phase 3 wire 110 KV feeder is tapped and brought to the Gang operated (GO) switch. The GO switch consists of isolators connected in each phase of the 3 phase line. 2. From the isolator the 110KV line is brought to the 110 KV Bus bar through Circuit Breaker (CB).  3. From the 110KV Bus bar, the 110 KV line is fed to the HT side of the 110KV/11KV stepdown transformer through Isolator. The transformer steps down the voltage to 11KV.  4. In fig.1.2. two 110/11KV transformers are connected from the 110 KV bus bar and the LT side of the power transformers are connected to the common 11KV Bus  through CB and Isolators. 5. From the 11KV Bus bar no of feeders are taken through  isolator and CB.  6. Lighting arresters are provided for protection from lightning and current transformers for...
Post a Comment
Read more

single bus bar and single busbar with sectionalisation

                                            BUS BAR 1.                               SINGLE BUS BAR                 In this way, only one set bus - bar is attached to the entire generating station.  All transformers, generators and feeders are connected to this single bus - bar.  Generators are connected to the bus - bar via isolator and circuit breakers.  Similarly to incoming and outgoing feeders via isolator and circuit breakers are attached with bus bar. This system will suitable for both A.C and D.C ADVANTAGES:                         1.  Only one circuit breaker is required for each                ...
Post a Comment
Read more

ELECTRICAL TRACTION

                              ELECTRICAL TRACTION : ELECTRIC TRACTION :            Electric traction means a locomotion in which the driving force is derived from electric motors.  There are many advantages of electric traction over other forms of jocomotion in the current days of traction in any country of development.  In fact, it is a fast-paced, safest and economical way of transporting and transporting goods to the modern day. In this type of drive the locomotive is equiped with a d.c series motor or ac series motor or three phase induction motor. The electric energy is directly fed into the motor and torque developed by the propelling the train.                             TRACTION SYSTEMS : The most commonly used traction methods are as follows. 1.  Steam engine drive...
Post a Comment
Read more