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Miniature Circuit Breakers

Miniature Circuit Breakers
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Miniature Circuit Breakers

Product catalog summary
General Information
Sigma Miniature Circuit Breakers (MCBs) are designed to protect electrical circuits from short circuits and overloads. They are available in breaking capacities of 3 kA, 4.5 kA, 6 kA, 10 kA, and 16 kA, and comply with standards EN 60898-1, EN 60947-2, VDE 0660, and the Low Voltage Directive (LVD) 73/23/EEC.
Technical Specifications
  • 3 kA MCB: Rated current from 2 to 63 A, voltage of 240/415 V AC, breaking capacity of 3 kA.
  • 4.5 kA MCB: Similar to 3 kA but with 4.5 kA breaking capacity.
  • 6 kA MCB: Rated currents up to 125 A, breaking capacity of 6 kA, enhanced mechanical life.
  • 10 kA MCB: Similar to 6 kA but with 10 kA breaking capacity.
  • 16 kA MCB: Rated for currents up to 125 A, breaking capacity of 16 kA.
All MCBs have an IP 20 protection class and operate in temperatures from -5°C to +40°C.
Installation and Service Conditions
MCBs are mountable on a 35 mm DIN rail, support cable connections up to 25 mm², and function at altitudes up to 2000m with relative humidity up to 50% at 40°C.
Tripping Characteristics and Selection
MCBs are categorized by tripping characteristics: Type B for low inductive loads, Type C for general applications, and Type D for high inrush currents. Tripping times vary to ensure protection without unnecessary interruptions.
Protection of DC Circuits
MCBs maintain thermal characteristics in AC or DC applications, with magnetic trip values increasing by 40% for DC circuits. Full rated breaking capacity is achievable by connecting poles in series for higher DC voltages.
Influence of Non-Standard Frequencies
Magnetic tripping values increase by up to 40% for frequencies above 50/60Hz.
Protection of Motors
MCBs protect motors against internal short circuits while allowing short-duration overcurrents during start-up.
Overview
This document provides detailed specifications and guidelines for selecting and using MCBs for various applications, focusing on lighting circuits and three-phase induction motors. It includes technical specifications, tripping curves, and order information for different MCB models.
Specifications
The document lists MCB specifications for different power ratings, starting currents, and tripping curves. It categorizes MCBs based on rated power (kW and Hp), starting current (A), and tripping curves (C or D type).
Lighting Circuit Protection
The document emphasizes selecting the correct MCBs for lighting circuits, considering lamp power, type, and peak currents. C type MCBs are generally recommended for these applications.
Fluorescent and Sodium Vapor Lamps
Tables provide current ratings for various types of fluorescent and sodium vapor lamps, aiding in determining the maximum number of lamps that can be protected by a specific MCB.
MCB Accessories
Accessories such as shunt trip releases and fault signal contacts allow for remote tripping and signaling. Specifications for these accessories, including rated operating voltage and frequency, are provided.
Order Information
The document includes order codes and packaging details for various MCB models, categorized by rated current, number of poles, and tripping curves (B, C, and D types).
Technical Diagrams
Wiring diagrams and dimensions for different MCB models are included, offering visual guidance for installation and integration into electrical systems.
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Catalog excerpts

Miniature Circuit Breakers-2

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

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Miniature Circuit Breakers-4

CIRCUIT BREAKER 4.5 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

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Miniature Circuit Breakers-5

CIRCUIT BREAKERS 6 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

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Miniature Circuit Breakers-6

10 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

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CIRCUIT BREAKERS 16 kA Miniature Circuit Breaker Technical Specifications Tripping Characteristics

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Miniature Circuit Breakers-8

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 has...

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Miniature Circuit Breakers-9

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 produce...

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Miniature Circuit Breakers-10

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 any...

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Miniature Circuit Breakers-11

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 54...

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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 currents...

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Miniature Circuit Breakers-13

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 According...

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Miniature Circuit Breakers-14

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 Contact...

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CIRCUIT BREAKERS Remote Control Shunt Trip Release Fault Signal Contact

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

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*Prices are pre-tax. They exclude delivery charges and customs duties and do not include additional charges for installation or activation options. Prices are indicative only and may vary by country, with changes to the cost of raw materials and exchange rates.