MOLDED CASE CIRCUIT BREAKERS

Circuit Breakers (Thermal-Magnetic) MCCB I CONTENTS Circuit Breakers (Electronic) MCCB Types of Circuit Breakers 4 Parts of Circuit Breakers 5 Earth Leakage Protection Circuit Breaker (ELCB) 7 Earth Leakage Protection Relay 8 Network Protection Breakers 9 Generator Circuits Protection Breakers 9 Motor Circuits Protection Breakers 10 Three-phase electronic circuit breakers 10 Single-phase thermal-magnetic circuit breakers 10 Max. Current Load Capacity Of Products In Different 11 Utilization of Circuit Breakers in Direct Current Circuits 11 Circuit Breakers Protecting Capacitor Circuits 12 Breakers...

MOLDED CASE CIRCUIT BREAKERS Thermal-Magnetic Circuit Breakers • □ standard, □ upon request. • 3> les : O -1 - CO -1 - CO test (O : Open maneuver, CO : Close - Open maneuver, • CD see technical characteristic tables for products with t: Waiting duration) value. (Page 8-9) • ® Connection sections are given in accordance with EN 60947-1 standard. • ® leu: O-t-CO test (O: Open maneuver, • © Accessories can be easily mounted by the user by opening the front cover of CO : Close - Open maneuver, t: Waiting duration) circuit breakers. (Plug-In)

MOLDED CASE CIRCUIT BREAKERS • (D 800A'de 500-800A thermal adjustment area is standard Note: F21 and F31 type of circuit breakers are manufactured as with fixed • © Adjustment area for 160A is (0,8-1) In thermal magnetic or adjustable thermal-magnetic ((5-10)ln) depending or • 9 Adjustment area for 125,160A is (5-10) In - for 400A is (3-8)ln request. • ® Value at 240V- for F01 - F02 type breakers

MOLDED CASE CIRCUIT BREAKERS Electronic Circuit Breakers • © As an additional protection against short circuit currents in federal electronic circuit breakers, mechanical opening mechanism operating with magnetic field of the short circuit current has been placed on each phase. In this way, mechanical opening unit is open in over currents such as short circuit and risk of not opening in case of electronic card failure has been eliminated. This is a great advantage of Federal circuit breakers. • ~\ standard, ~\ upon request. • CD see technical characteristic tables for products with • <B leu:...

MOLDED CASE CIRCUIT BREAKERS The circuit breaker is a mechanical opening-closing device, which is used for closing, breaking, separating circuit Arc and carrying current of that circuit under extinguisher ordinary conditions and for automatically I breaking the circuit under extraordinary conditions like short circuit and over l= Current passing through t= Current passing duration F4: Under voltage release (UVR) Operating Principle of the Circuit The most important function of the circuit breaker, in addition to opening-closing the circuit, is to protect the circuit under extraordinary conditions....

MOLDED CASE CIRCUIT BREAKERS Moving contact Magnetic area I max :Peak value of expected short circuit current. I limit:Peak value of limited short circuit current. Circuit breaker without limiter Circuit breaker with limiter The only difference between circuit breakers with and without limiters is in the construction of fixed contacts. Fixed contacts of circuit breakers with limiters are in the structure to reverse the direction of current and form reverse magnetic force to push the moving contact. Magnetic protection function, >3 x In: (For protection under short circuit Another function of...

MOLDED CASE CIRCUIT BREAKERS Magnetic area Current direction Contacts, which are made of silver- graphite alloys with a smoothers structure, are used in fixed (bottom) contacts, silver - wolfram contacts, which are harder, are used in moving (top) contacts. A swaged structure has been ensured in moving contacts. In this way, swaged and hard alloy contacts have a place on soft fixed contacts in each opening-closing. In this way, the lowest resistance is ensured. Moving contact should touch the fixed contact very well in order to have low contact resistance. However, excessive contact pressure...

MOLDED CASE CIRCUIT BREAKERS EARTH - LEAKAGE CIRCUIT BREAKER (ELCB) Against earth leakage currents resulting from the low voltage circuits, with combination of fault current sensor relay and toroidal transformer are detected and controlling of shunt trip coil or under voltage release coil on the mounted circuit breakers, such as protection can be achieved by residual current protected type circuit breakers. Toroidal transformer, sensors relay and shunt trip are placed into circuit breakers. Without the need any external accessory connector can be installed only by connecting the input and output...

MOLDED CASE CIRCUIT BREAKERS Important considerations in assembly: - Cables should pass through center of the toroidal transformer to the extent possible. - Toroids with appropriate diameters should be utilized. Utilization of toroids with higher diameters shall reduce sensitivity. Different Connections: • If cables cannot pass through a toroid with high diameter, several toroids can be connected parallel to the same ground detection relay. However, this transaction reduces sensitivity of the device and increases opening threshold. • If it is not possible to place the toroid around primary busbars,...

MOLDED CASE CIRCUIT BREAKERS Network Protection Breakers: Big powerful motor, load with starting resistance don't exist in main networks and lines are quite long. LV circuit breaker should open in short circuit currents to occur by the end of these lines. Therefore, magnetic adjustments of the circuit breakers utilized in main lines should be between (4 - 8)xln. Three-phase thermal-magnetic circuit breakers / For protection of main networks: □: Please enter amper value Short circuit current of a generator Ikg short circuit current (A) (Reactance observed around 5-20% of the impedance value Is...

MOLDED CASE CIRCUIT BREAKERS Motor Circuit Protection Breakers: Motors draw very high current for a short time during first start-up. In order to ensure operating continuity and to protect the system, magnetic adjustment area of the breaker to be selected should be (8 - 12)xln. Three-phase thermal-magnetic circuit breakers / For protection of motor circuits: Reasons for Over Voltages Occurring at L.V. Facilities and the Measures that Must Be Taken: As known, over voltages may develop at power plants from time to time. These over voltages develop as a sudden impact for a very short time during...