Miniature Circuit Breakers
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MINIATURE CIRCUIT BREAKERS MCB General Information Sigma MCBs are such devices that protect their connected circuits against short circuit and overload. Sigma MCBs produced as 3 kA, 4.5 kA, 6 kA, 10 kA and 16kA according to the EN 60898-1, EN 60947-2 and VDE 0660. They are also conforming to the Low Voltage Directive (LVD) 73/23/EEC. 1 2 3 4 3 kA MCB 4.5 kA MCB 6 kA MCB 5 10 kA MCB 6 7 7 8 9 9 9 10 11 13 14 15 Handle Tripping mechanism Magnetic coil Connection terminals Fixed contact Bi-metal Arc Extinguisher The main components that make up a miniature circuit breaker www.sigmaelektrik.com 1

CIRCUIT BREAKER 4.5 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

CIRCUIT BREAKERS 6 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

10 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

CIRCUIT BREAKERS 16 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

MINIATURE CIRCUIT BREAKERS MCB Installation Up to 25 mm2 cable can be connected to the sigma MCBs, which are designed to be easily mounted on to the 35 mm DIN rail according to EN 50022. Besides, connection with collective MCB Bus bar is possible. Maximum torque applied for connection screws is 2 Nm. Higher torque may damage to the screws or terminal connections. Although Sigma MCBs have availability to make energy entrance from both upper side and under side, it is recommended to make from upper side. Connection Terminals own IP20 protection degree according to the EN60529. The Design that...

MINIATURE CIRCUIT BREAKERS MCB minute minute Second Second minute Second Tripping Characteristics And Selection Application Selection For MCB Tripping Characteristics I 1 I 2 I 3 I 4 Thermal Non Tripping Current Type B characteristics are suitable for moderately inductive loads having that have little or no switching surges i.e. electric heating, water heating, ovens etc. Thermal Tripping Current Type C characteristics MCBs can be used in general applications such as lighting, ring/radial socket outlets and small motors. Magnetic Non-tripping Installations where the equipment is likely to...

MINIATURE CIRCUIT BREAKERS MCB Protection Of The DC Circuits The thermal characteristics for Sigma MCBs are unaffected by the type of current applied, that is either direct current or alternating current. The magnetic trip value increases by 40%. For example, in the case of a breaker of tripping characteristics B and 10A rated current, its magnetic tripping value will be between 30A and 50A in alternating current. The magnetic tripping value for the same breaker in direct current will be between 42.4A and 70.7A For DC service, the MCBs full rated breaking capacity can be achieved without...

MINIATURE CIRCUIT BREAKERS MCB Protection Of Motors The protection of motors against the effects of an internal short circuit must be ensured, allowing at the same time the presence of short duration overcurrents (starting) without causing tripping of the protection element. This element must also ensure protection of the line, of the contactor and of the thermal relay associated to the motor. 220-240 V Single Phase Induction Motor Rated Power Miniature Circuit Breaker Rated Current (A) Starting Current (A) Tripping Curve Rated Current(A) 0.25 1.5 18 C or D 6 0.5 3 36 C or D 6 0.55 0.75 4.5...

MINIATURE CIRCUIT BREAKERS MCB Protection Of The Lighting Circuits When choosing the MBCs for protection of lighting circuits, it should be considered the power of the lamp, kind of the lamp, number of lamps and high peak currents when the lamps are energized. In the lighting circuits consisted of Sodium and Mercury vapor discharge lamps,the peak currents may occur up to 25 times of the rated current at the first 3 ms. Following this, 7 times of the rated current may be drawn within 2 seconds. In the lighting circuits,inwhich there is electronic ballast worked with high frequency ,the peak...

MINIATURE CIRCUIT BREAKERS MCB Maximum Number Of Fluorescent Lamps That Can Be Protected According To MCB’s Ampere TC-L 24 W TC-D + T26 W TL + TC-L 36 W TL 58 W TC9/11 W TC-D 13/18 W TC 18 W TC-L 18/24 W TC-D + -T 26 W TL-TC-L 36 W TL 58 W 62 47 27 30 23 14 10 99 99 44 44 27 16 100 75 43 48 37 23 16 159 159 71 71 44 20 125 94 53 60 46 28 20 201 201 89 89 56 25 156 115 66 75 57 36 25 250 250 110 110 71 Rated Current Of MCB (A) TL + TC-L 18W 10 Rated Current Of MCB (A) TC-D 13 W Compensated TC 9/11 W TC-D 13 W Not Compensated Maximum Number Of Sodium Vapor Lamps That Can Be Protected...

MINIATURE CIRCUIT BREAKERS MCB MCB Accessories It is possible to make tripping and signalling remotely to the Sigma 6 kA and 10 kA MCBs by adding shunt trip and fault signal contact. Fault signal contact are mounted to the left side of the surface of the MCBs or Shunt Trip and when the MCBs are tripped because of the overload or short circuit, the contacts change the position however when the MCBs open or close the circuit by manually, the contacts do not change the position. Type Code Properties Order code SMAB 110 - 415 V AC / 110-220 V DC Shunt Trip Release SMAB220 SMYK 1N0 + 1NC Signal...

CIRCUIT BREAKERS Remote Control Shunt Trip Release Fault Signal Contact

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CIRCUIT BREAKER

CIRCUIT BREAKERS

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CIRCUIT BREAKER Wiring Diagram ^fps. C CIc Tripping Curve Wiring Diagram