Introduction
In modern large-scale industrial power distribution systems, the main incoming circuit breaker undertakes the core protection task of the entire system, and its reliability, accuracy, and intelligence directly affect the continuity of power supply and equipment safety. The Megatiker M5 electronic circuit breaker launched by BTicino, as the flagship product of the Megatiker platform, is designed for large capacity current levels from 500A to 1600A. It adopts advanced electronic protection units, providing up to 100kA breaking capacity, accurate overload and short-circuit protection, as well as comprehensive power measurement and communication functions.
This article is based on the official technical documentation of BTicino, systematically reviewing the technical characteristics, electrical parameters, electronic protection unit functions, installation methods, accessory configurations, and trip characteristics of the Megatiker M5 electronic circuit breaker, providing professional references for engineers and system integrators.
Product positioning and scope
1. Product positioning
The Megatiker M5 series is positioned as the main incoming line protection for the high-end industrial power distribution market, with the following characteristics:
Large capacity: rated current covering 500A to 1600A
High segmentation capability: up to 100kA
Intelligent protection: electronic release unit, supporting multiple protection types such as Li, Lsi, Lsig
Integrated measurement: Real time monitoring of parameters such as current, voltage, power, and electrical energy
Flexible Installation: Supports both fixed and pull-out installation methods
Communication capability: Supports MODBUS RS485 communication for easy integration into monitoring systems
2. Product Scope
Electronic circuit breaker
According to different breaking capabilities, M5 circuit breakers are divided into four levels:
Breaking ability level Breaking ability Icu (415V AC)
F (36kA) 36 kA
N (50kA) 50 kA
H (70kA) 70 kA
L (100kA) 100 kA
Rated current levels: 500A, 630A, 800A, 1000A, 1250A, 1600A
Extremes: 3P and 4P versions
Size and weight
The M5 series adopts a large-sized modular design, suitable for high current applications:
Parameters 3P 4P
Width (W) 210 mm 280 mm
Height (H) 320 mm 320 mm
Depth (D) 140 mm 140 mm
Pole spacing 70 mm 70 mm
Weight Reference
Component weight (kg)
Fixed circuit breaker (3P) 18 kg (1250A)/18 kg (1600A)
Fixed circuit breaker (4P) 20 kg (1250A)/21.5 kg (1600A)
Pull out base (front wiring)+18 kg (3P)/+21.5 kg (4P)
Pull out base (rear wiring)+21.7 kg (3P)/+26.2 kg (4P)
Debro lift mechanism+9.9 kg (3P)/+11.2 kg (4P)
Supply content and installation method
1. Factory standard configuration
Each M5 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
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 500/630/800/1000/1250/1600 A
Pole number 3P/4P
Rated insulation voltage Ui 1000 V AC
Rated working voltage Ue 690 V AC
Rated impulse withstand voltage Uimp 8 kV
Rated frequency 50/60 Hz
Working temperature range -25 ° C to+70 ° C
Mechanical lifespan of 10000 cycles
Mechanical lifespan (with electric operation) 5000 times
Electrical lifespan (In) 4000 times
Electrical lifespan (0.5 × In) 8000 times
Use category B
Suitable for isolation is
2. Breaking ability (Icu)
The breaking capacity of M5 circuit breaker at different voltage levels is as follows:
Voltage 36kA (F) 50kA (N) 70kA (H) 100kA (L)
220/240V AC 70 kA 100 kA 105 kA 150 kA
380/415V AC 36 kA 50 kA 70 kA 100 kA
440/460V AC 30 kA 45 kA 65 kA 80 kA
480/500V AC 25 kA 35 kA 45 kA 55 kA
480/550V AC 20 kA 24 kA 28 kA 30 kA
600V AC 20 kA 24 kA 28 kA 30 kA
690V AC 14 kA 20 kA 22 kA 25 kA
3. Short circuit breaking capacity (Ics) during operation
F/N/H level: Ics=100% Icu
L level: Ics=70% Icu
4. Rated short-circuit making capacity (Icm @ 415V)
Breaking ability level Icm
F (36kA) 76.5 kA
N (50kA) 105 kA
H (70kA) 154 kA
L (100kA) 220 kA
Electronic protection unit
The core of the M5 series is its advanced electronic protection unit, which provides multiple protection types and precise adjustment functions.
1. Protection type
Li type protection
Long delay protection (L): Overload protection based on effective current value
Ir adjustable: 0.4 to 1 × In (1A step)
Tr options: 3s, 5s, 10s, 15s, 20s, 25s, 30s (7 levels)
Instantaneous protection (I): Short circuit instantaneous protection
Fixed threshold: 500-1250A is 15kA, 1600A is 20kA