BTicino Megatiker M4 Circuit Breaker

BTicino Megatiker M4 Circuit Breaker

Introduction

In industrial power distribution systems, high-capacity circuit breakers are the core protective components of main incoming cabinets and large distribution cabinets. The Megatiker M4 series launched by BTicino, as an important component of the Megatiker platform, is designed specifically for current levels ranging from 250A to 630A, providing a breaking capacity of up to 100kA, meeting the dual requirements of high reliability and flexibility in industrial power distribution.

This article is based on the official technical documentation of BTicino, systematically reviewing the technical characteristics, electrical parameters, installation methods, accessory configurations, and trip characteristics of Megatiker M4 thermal magnetic circuit breaker and MS4 isolating switch, providing professional reference for engineers and system integrators.

Product positioning and scope

1. Product positioning

The Megatiker M4 platform is positioned in the high-end industrial power distribution market and has the following characteristics:

High power applications: rated current covering 250A to 630A

High segmentation capability: up to 100kA

Flexible installation: supports multiple installation methods including fixed, plug-in, and pull-out

Rich attachments: supports multiple functions such as leakage protection, electric operation, interlocking, etc

2. Product Scope

Thermal magnetic circuit breaker

According to different breaking capabilities, M4 circuit breakers are divided into four levels:

Breaking ability level, model code, breaking ability Icu (415V AC), number of poles

F (36kA) T743Fxxx / T744Fxxx / T742Fxxx 36 kA 3P / 4P / 3P+N/2

N (50kA) T743Nxxx / T744Nxxx / T742Nxxx 50 kA 3P / 4P / 3P+N/2

H (70kA) T743Hxxx / T744Hxxx / T742Hxxx 70 kA 3P / 4P / 3P+N/2

L (100kA) T743Lxxx / T744Lxxx / T742Lxxx 100 kA 3P / 4P / 3P+N/2

Rated current level: 250A, 320A, 400A, 500A, 630A

disconnecting switch

MS4 isolation switch is suitable for isolation applications that require visible breakpoints:

Rated current 3P model 4P model

400A T743S400 T744S400

630A T743S630 T744S630

Size and weight

The M4 series adopts a modular design for easy panel installation:

Parameters 3P 4P

Width (W) 140 mm 183 mm

Height (H) 260 mm 260 mm

Depth (D) 105 mm 105 mm

Pole spacing 42 mm 42 mm

Weight Reference

Component 3P weight (kg) 4P weight (kg)

Fixed circuit breaker 5.20 6.85

Fixed isolation switch 5.00 6.40

Plug in accessory (front wiring)+3.35+4.29

Plug in accessory (rear wiring)+3.55+4.79

Pull out attachment+2.30+5.50

Supply content and installation method

1. Factory standard configuration

Each M4 circuit breaker comes with the following accessories at the factory:

Fixed screws (4 for 3P, 4 for 4P)

Wiring screws (6 for 3P and 8 for 4P)

Interphase insulation partitions (2 pieces for 3P, 3 pieces for 4P)

2. Installation method

The circuit breaker supports the following installation directions:

Vertical installation: standard installation method

Horizontal installation: suitable for cabinets with limited space

Reverse feeding: Supports upper or lower input lines, no LINE/LOAD marking required for reverse feeding

3. Installation form

Fixed type: directly installed on the panel

Plug in: Installed through a dedicated base for quick replacement

Pull out type: equipped with a "Debro lift" mechanism, supporting live plugging and unplugging, with three positions for connection, testing, and disconnection

Electrical and mechanical characteristics

1. Technical parameters of circuit breaker

Parameter values

Rated current In 250/320/400/500/630 A

Pole number 3P/4P/3P+N/2

Rated insulation voltage Ui 800 V AC

Rated working voltage Ue 690 V AC

Rated impulse withstand voltage Uimp 8 kV

Rated frequency 50/60 Hz

Reference ambient temperature 40 ° C/50 ° C

Working temperature range -25 ° C to+70 ° C

Mechanical lifespan of 20000 cycles

Mechanical lifespan (with electric operation) 10000 times

Electrical lifespan (In) 4000 times

Electrical lifespan (0.5 × In) 8000 times

Use category A

Suitable for isolation is

2. Protection features

Overload protection (thermal): adjustable range from 0.8 to 1 × In

Short circuit protection (magnetic): adjustable range 5 to 10 × In

Neutral wire protection: The 4P version provides 100% phase pole protection

3P+N/2 version: The neutral wire protection current is 50% of the phase pole

3. Technical parameters of isolation switch

Parameter 400A model 630A model

Rated uninterruptible current Ie 400 A 630 A

Short time withstand current Icw (1s) 5 kA 8 kA

Rated short-circuit connection capacity Icm 8 kA 14 kA

Use category AC23A AC22A

Is it suitable for isolation

Mechanical lifespan 20000 cycles 20000 cycles

Electrical lifespan 4000 times 4000 times

Breaking ability and current limiting characteristics

1. Breaking ability (Icu)

The breaking capacity of M4 circuit breaker at different voltage levels is as follows:

Voltage 36kA (F) 50kA (N) 70kA (H) 100kA (L)

240V AC 70 kA 100 kA 105 kA 150 kA

415V AC 36 kA 50 kA 70 kA 100 kA

500V AC 25 kA 30 kA 40 kA 50 kA

690V AC 14 kA 18 kA 20 kA 22 kA

250V DC 35 kA 35 kA 35 kA 35 kA

2. Operating short-circuit breaking capacity (Ics)

F/N/H level: Ics=100% Icu

L level: Ics=70% Icu

3. Rated short-circuit making capacity (Icm)

Breaking ability level Icm @ 415V

F (36kA) 76.5 kA

N (50kA) 105 kA

H (70kA) 154 kA

L (100kA) 220 kA

Power loss

1. Power loss per pole of the circuit breaker (In=630A)

Connection method: Phase pole (W) Neutral pole (W)

Cage terminal 37.3 21.2

Wiring terminal 37.3 21.2

External wiring terminal 42.1 23.1

Expansion terminal 44.7 24.1

Rear wiring terminal 45.0 24.3

Plug in version 85.3 40.5

With leakage protection 57.2 28.2

2. Power loss per pole of isolation switch (In=630A)

Connection method: Phase pole (W) Neutral pole (W)

Cage terminal 37.3 37.3

Expansion terminal 44.7 44.7

Rear wiring terminal 45.0 45.0

Plug in version 85.3 85.3

With leakage protection 57.2 57.2

Reduced capacity usage

1. Temperature reduction

The ambient temperature has a significant impact on the current carrying capacity of circuit breakers. The following table shows the maximum continuous operating current at different temperatures:

In (A) 10°C 20°C 30°C 40°C 50°C 60°C 70°C

250 336 307 279 250 220 193 166

320 416 384 352 320 288 256 224

400 475 460 425 400 360 320 280

500 600 550 525 500 455 410 365

630 700 683 650 630 580 530 480

2. Altitude Capacity Reduction

When the installation altitude exceeds 2000 meters, it is necessary to reduce the capacity according to the following coefficient:

Altitude (m) ≤ 2000 3000 4000 5000

Working voltage Ue (V) 690 590 520 460

Rated current In 1 × In 0.98 × In 0.93 × In 0.9 × In

3. Environmental adaptability

Climate conditions: Complies with IEC/EN 60947-1 Appendix Q, Cat. F, suitable for temperature, humidity, vibration, shock, and salt spray environments

Electromagnetic compatibility: Complies with Appendix F of IEC/EN 60947-2

Pollution level: Level 3

Accessories and Options

The M4 series offers a wide range of electrical and mechanical accessories to meet different application needs.

1. Leakage protection module

Parameter standard type LED type

Type A - S A - S

Rated current 630A 630A

Rated voltage 500V AC 500V AC

Leakage action current I Δ n 0.03/0.3/1/3 A 0.03/0.3/1/3 A

Delay time Δ t 0/0.3/1/3 s 0/0.3/1/3 s

50% I Δ n pre alarm: None

Model (400A) T7082/400 T7081/400

Model (630A) T7092/630 T7091/630

2. Release device

Split release (ST)

Voltage specifications: 24V, 48V, 110-130V, 220-250V, 380-440V (AC/DC)

Voltage range: 70% to 110% Un

Action time: ≤ 50 ms

Power consumption: 300 VA/W

Undervoltage Release (UVR)

Voltage specifications: 24V AC/DC, 48V DC, 110-125V AC, 220-240V AC, 380-415V AC

Operating voltage: 35% to 70% Un

Reset voltage: 85% to 110% Un

Action time: ≤ 50 ms

Delay module: can be equipped with 800ms delay module (M7000E/024, M7000MR/230, M7000MR/400)

3. Auxiliary contacts

Model: M7X01

Contact form: 1NO/NC conversion contact

Rated current: 3A @ 250V AC

Configuration: M4 supports a maximum of 2 auxiliary contacts, 1 fault signal contact, and 1 release

4. Rotate the handle

Type and Model Description

Direct standard M7447 black handle

Direct emergency M7R14 red/yellow handle

Variable depth standard T7449 IP55, black

Variable depth emergency T7449E IP55, red/yellow

Lock attachment M7R17 for variable depth handle, requires universal lock cylinder

5. Electric operating mechanism

Energy storage electric operating mechanism

Model: M7475P/024, M7475P/048, M7475P/110, M7475P/230

Voltage: 24V, 48V, 110V, 230V AC/DC

Closing time: ≤ 100 ms

Energy storage time: ≤ 2 seconds

Mechanical lifespan: 10000 cycles

Direct acting electric operating mechanism

Model: M740230

Voltage: 230V AC

Closing time: ≤ 550 ms

Opening time: ≤ 450 ms

Mechanical lifespan: 10000 cycles

6. Connect attachments

Cage terminal

Standard type: M7400, supports 1 × 240mm ² (flexible) or 1 × 300mm ² (rigid)

High capacity type: M7400/2, supports 2 × 185mm ² (flexible) or 2 × 240mm ² (rigid)

Expansion terminal

3P model: M7430/3

4P model: M7430/4

Rear wiring terminal

3P model: M7450/P

4P model: M7451/P

7. Insertion and extraction attachments

Insertion attachment

Special terminals: M7B11 (3P), M7B12 (4P)

Front wiring base: M7B13 (3P), M7B14 (4P)

Rear wiring base: M7B15 (3P), M7B16 (4P)

With leakage base: M7B17 (4P front wiring), M7B18 (4P rear wiring)

Pull out the handle: M7B19

24 pin connector: M7B20

Pull out attachment (Debro lift mechanism)

Base: M7B22 (3P), M7B23 (4P), M7B24 (4P with leakage)

Position signal contact: M7T910N

Pull out the handle: M7T412

Auxiliary contact: M7B21 (up to 2)

8. Mechanical accessories

Padlock: M7045, used to lock in the "off" position

Interphase insulation partition: M7295

Terminal protective cover: M7475 (3P), M7476 (4P)

IP20 terminal cover: M7C11 (3P), M7C12 (4P)

9. Universal key lock

Support locking of rotating handle, electric operating mechanism, insertion mechanism, and extraction mechanism:

Lock cylinder type and model

Randomly encoded flat key M7K01

Fixed code EL43525 M7K02

Fixed code EL43363 M7K03

Randomly encoded star key M7K04

Release curve and current limiting curve

1. Thermal magnetic release curve

The M4 circuit breaker provides a typical thermal magnetic trip curve, including:

Cold state characteristic (curve 1): the action time of the circuit breaker when it is in a cold state

Curve 2: The operating time of a circuit breaker when it is in a hot state

The overload protection section has inverse time characteristics, while the short circuit protection section has instantaneous action with adjustable action values (5-10 × In).

2. Through the energy curve (I ² t)

The allowable energy of the circuit breaker under different expected short-circuit currents is displayed through the energy curve. A lower I ² t value means better protection for downstream equipment, reducing thermal and mechanical stress.

3. Peak current cut-off curve

The peak current cutoff curve shows the peak current that a circuit breaker can limit in the event of a short circuit fault. The curve, with the expected short-circuit current (RMS) as the horizontal axis and the actual allowable peak current as the vertical axis, intuitively reflects the current limiting performance of the circuit breaker.

DC application

M4 circuit breakers and isolating switches are also suitable for DC systems, and the appropriate number of poles in series should be selected according to the voltage level.

1. DC breaking capacity (circuit breaker)

Pole series 60V DC 110V DC 250V DC

1 pole 35 kA --

2-pole series 35 kA 35 kA 35 kA

3-pole series 35 kA 35 kA 35 kA

Note: The above data applies to ungrounded DC networks with voltage tolerances ranging from 0% to+5%.

2. DC usage category (isolating switch)

MS4 isolation switch is suitable for DC-23A use in DC applications. Category:

Pole series 60V DC 110V DC 250V DC 500V DC

1-pole DC-23A --

2-pole series DC-23A DC-23A DC-23A-

3-pole series DC-23A DC-23A DC-23A-

4-pole series connection DC-23A DC-23A DC-23A DC-23A

Compliance and Certification

The Megatiker M4 series products comply with the following standards and regulations:

Product standards: IEC/EN 60947-2 (circuit breaker), IEC/EN 60947-3 (isolating switch)

International certifications: IECEE CB certification, LOVAG certification

Regional certification: CCC (China), EAC (Eurasian Union)

Ship certification: Lloyd's Register, RINA, Bureau Veritas Marine

Environmental directives: REACH, RoHS, WEEE (RAEE)

Environmental Product Declaration: PEP Ecopassport is available

The product label clearly indicates manufacturer information, model code, standard compliance, breaking capacity level (identified by color), barcode and other information for easy on-site identification and traceability.

Application scenarios and selection suggestions

1. Typical applications

Main incoming power distribution: incoming cabinets for factories, commercial buildings, and data centers

Distribution cabinet: Large equipment distribution circuit

Motor control: High power motor starts directly

Power switching: Switching between primary and backup power sources in ATS system

2. Key selection points

Rated current: Select specifications from 250A to 630A based on the load current

Breaking capacity: Select F/N/H/L level based on system short-circuit current

Installation method: fixed, plug-in or pull-out

Protection function: Do you need leakage protection or electric operation

Attachment requirements: auxiliary contacts, shunt release, rotating handle, interlock, etc

Environmental conditions: Temperature, altitude, humidity need to be considered for capacity reduction