⎯⎯ Electrical Protection Devices
Miniature Circuit Breaker
VIOX Miniature Circuit Breakers are designed for compact overcurrent protection in residential, commercial, and modular panel applications. This page focuses on the MCB product family: what it does, how the lineup is structured, which specifications matter, and how to choose the right model for the circuit.
⎯⎯ At a Glance
Core Product Highlights
What an MCB Does
Typical Applications
Key Selection Factors
Model Coverage
Certified By
⎯⎯ Overview
What Is an MCB?
A Miniature Circuit Breaker (MCB) is a compact protective device used to interrupt a circuit when current rises above the acceptable level for the wiring or connected load. In practical low-voltage systems, it is one of the most common devices used for branch-circuit protection.
MCBs are widely used because they are modular, DIN-rail friendly, easy to standardize in panel layouts, and available in multiple pole and trip-curve configurations. They are especially well suited to distribution boards where compact size and repeatable product selection matter.
⎯⎯ MCB Models
VIOX MCB Product Lineup
General Modular Range
VOB3-63
- Poles: 1P, 2P, 3P, 4P
- Rated current: 1A to 63A
- Curve code: B, C, D
- Rated voltage: 240/415V~ to 415V
Higher Performance
VOB4-63
- Poles: 1P, 2P, 3P, 4P
- Rated current: 1A to 63A
- Breaking capacity options: 6kA or 10kA
- Trip unit: thermal-magnetic
High Current Range
VOB4-125
- Poles: 1P, 2P, 3P, 4P
- Rated current: 80A, 100A, 125A
- Curve code: C, D
- Suitable for higher-current modular applications
High Current Range
VOB5-125
- Poles: 1P, 2P, 3P, 4P
- Rated current: 80A, 100A, 125A
- Curve code: C, D
- Suitable for higher-current modular applications
⎯⎯ Specification Focus
Key Specifications That Shape MCB Selection
| Specification Item | Why It Matters | Typical VIOX Page Direction |
|---|---|---|
| Pole Configuration | Determines how the MCB fits single-phase or multi-pole circuit arrangements | 1P to 4P modular formats across the lineup |
| Rated Current | Defines the circuit protection range and application fit | Compact range from low-current branch use to higher-current modular models |
| Breaking Capacity | Must align with available fault level and project expectations | 6kA and higher-performance options depending on series |
| Trip Curve | Affects compatibility with lighting, general loads, and inrush-heavy equipment | B, C, and D curve families available across key models |
| Voltage Rating | Must match the installation system and pole arrangement | Series-specific AC voltage coverage for common modular applications |
| Standards Context | Influences export fit, technical approval path, and documentation alignment | Review model series against the target market and product documentation |
⎯⎯ Trip Characteristics
MCB Curve Types at a Glance
Curve B
Lower Inrush Applications
Often associated with lighting and more resistive circuit behavior where faster magnetic response is acceptable.
Curve C
General Distribution
Typically used in general-purpose distribution and mixed-load environments where moderate inrush tolerance is preferred.
Curve D
Higher Inrush Loads
Commonly considered for loads with higher starting current, depending on the equipment and full circuit design.
⎯⎯ Application Fit
Where VIOX MCBs Are Used
Residential
Home Distribution Boards
Suitable for lighting circuits, socket outlets, and compact branch protection where modular DIN rail layout is standard.
Commercial
Retail and Office Panels
Useful in final distribution boards that need clear branch-circuit protection and repeatable model selection.
Panel Building
Higher Inrush Loads
Commonly considered for loads with higher starting current, depending on the equipment and full circuit design.
⎯⎯ Selection
How To Choose the Right MCB
STEPS
- Start with the circuit type and expected load behavior.
- Confirm the required pole format for the distribution arrangement.
- Check the current rating and project fault level before selecting breaking capacity.
- Choose the trip curve that best fits the load profile.
- Review the target market and product documentation requirements.
TIPS
| Selection Factor | Why It Matters | Common Mistake |
|---|---|---|
| Current Rating | Must align with the circuit protection strategy | Choosing by load label alone |
| Breaking Capacity | Must match or exceed the installation fault condition | Using one default value for every project |
| Trip Curve | Controls how the device reacts to inrush and fault conditions | Ignoring the load profile |
| Pole Format | Must fit the circuit arrangement | Selecting only by price or series familiarity |
| Market Context | Affects the standards and model fit expected by the buyer | Mixing product assumptions across markets |
⎯⎯ FAQ
Frequently Asked Questions
What does an MCB protect against?
An MCB protects a circuit against overload and short-circuit conditions.
Where are MCBs commonly used?
They are commonly used in residential distribution boards, commercial branch circuits, and modular electrical panels.
How is an MCB different from an MCCB?
An MCB is a compact modular breaker for smaller low-voltage distribution applications, while an MCCB generally covers larger current ranges and broader protection adjustment needs.
What should I review before choosing an MCB model?
Review the current rating, pole format, breaking capacity, trip curve, voltage fit, and the technical expectations of the target market.
What is the next step after choosing an MCB family?
After identifying the right family, the next step is usually confirming the current rating, pole format, trip curve, and breaking capacity against the actual circuit design and panel layout.
⎯⎯ Next Step
Need Catalogs, Specs, or Model Selection Support?
The VIOX MCB range is organized to support catalog review, specification confirmation, and practical model comparison across modular circuit protection applications.
Product Notes
Key product considerations include trip curve choice, breaking capacity alignment, pole configuration, and fit with the intended distribution board layout.
