VF003 ミニチュアサーキットブレーカ（MCB）

What is the VIOX VF003 Miniature Circuit Breaker?

The VF003 is a premium miniature circuit breaker (MCB) designed for comprehensive electrical protection in residential, commercial, and industrial applications. This NF-certified circuit breaker provides reliable protection against short-circuit currents, overload conditions, and serves as an effective isolation switch in electrical distribution systems.

Why Choose the VF003 MCB for Your Electrical Installation?

In today’s electrical systems, safety and reliability are paramount. The VIOX VF003 miniature circuit breaker stands out as a versatile protection device with multiple certifications (NF, UKCA, CE) and exceptional performance characteristics. Whether you’re working on domestic installations or complex industrial systems, the VF003 MCB offers the protection and functionality needed for modern electrical networks.

Key Features and Benefits of the VF003 Miniature Circuit Breaker

Superior Protection Mechanism

The VF003 MCB features a dual protection system:

• Thermal protection: Guards against prolonged overload conditions
• Magnetic protection: Provides instant tripping during short-circuit events

This comprehensive protection mechanism ensures your electrical systems remain safe under various fault conditions, preventing damage to connected equipment and reducing fire hazards.

Versatile Current Ratings

The VF003 is available in multiple current ratings to suit various application requirements:

• 2A, 6A, 10A, 16A, 20A, 25A, and 32A

This range allows electrical designers and installers to select the precise rating needed for specific circuit loads, providing optimal protection without unnecessary tripping.

Multiple Trip Curve Options

The VF003 MCB offers specialized tripping curves tailored to different application needs:

• B curve (3-5In): Ideal for protecting people and long cable runs in TN and IT systems
• C curve (5-10In): Perfect for resistive and inductive loads with low inrush current
• D curve (10-14In): Designed for circuits supplying loads with high inrush current at circuit closing (LV/LV transformers, breakdown lamps)

This variety allows for precise protection coordination based on the specific characteristics of your electrical installation.

High Breaking Capacity

With breaking capacities of 3000A, 4500A, and 6000A, the VF003 MCB can safely interrupt high fault currents, providing robust protection even in demanding industrial environments.

Technical Specifications: VF003 Miniature Circuit Breaker

Electrical Features

パラメータ	仕様	スタンダード
モデル番号	VF003	IEC/EN 60898-1
ポール	1P+N
定格電流 In	2A, 6A, 10A, 16A, 20A, 25A, 32A
定格電圧 Ue	120V, 230/400V ~ 240/415V
絶縁電圧 Ui	500V
定格周波数	50/60 Hz
Rated breaking capacity	3000A, 4500A, 6000A
Energy limiting class	3
定格インパルス耐電圧(1.2/50) Uimp	4000V
誘電体試験電圧1分間の周波数	2Kv	1.89kV
汚染度	2
Thermo-magnetic release characteristic	B, C	(8 – 12) In
電気的寿命	10,000

機械的特徴

パラメータ	仕様
機械的寿命	20,000 cycles
接点位置インジケーター	はい
保護等級	IP20
Reference temperature for setting of thermal element	30°C
周囲温度（日平均≤35℃の場合）	-5°C to 40°C
保存温度	-25°C～70°C

Installation Specifications

パラメータ	仕様
端子接続タイプ	Cable/U-type busbar/Pin-type busbar
ケーブル用端子サイズ	25 mm² / 18-4 AWG
バスバー用端子サイズ上部/下部	10 mm² / 18-8 AWG
締め付けトルク	2.5 N·m / 22 In-lbs.
取り付け	ファストクリップ装置によりDINレールEN 60715 (35mm) に取り付け可能
接続	上から

Accessory Compatibility

特徴	Availability
補助接点	はい
Shunt release	はい
Under voltage release	はい
アラーム接点	はい

Applications of the VF003 Miniature Circuit Breaker

住宅用電気システム

The VF003 MCB is perfect for home electrical installations, providing:

• Protection for lighting circuits
• Safety for power outlets
• Overload protection for household appliances
• Short-circuit protection for domestic wiring

Commercial Buildings

In commercial environments, the VF003 offers:

• Reliable protection for office equipment
• Security for lighting systems
• Safety for HVAC systems
• Protection for sensitive electronic equipment

産業用途

For industrial settings, the VF003 provides:

• Motor protection (with appropriate rating selection)
• Control circuit protection
• Distribution board safety
• Equipment isolation capability

Selection Guidelines for the VF003 MCB

How to Choose the Right Current Rating

1. Calculate the load current: Determine the maximum continuous current your circuit will carry
2. Apply safety factor: Select an MCB rating that’s approximately 25% higher than the calculated load current
3. Consider startup currents: For motors and other high-inrush equipment, factor in the starting current
4. Check cable ratings: Ensure the selected MCB rating is compatible with the installed cable size

How to Select the Appropriate Trip Curve

• Bカーブ: Select for residential lighting, socket outlets, and general purpose circuits
• Cカーブ: Choose for small transformers, fluorescent lighting, and standard motors
• Dカーブ: Use for transformers, motors with high starting currents, and welding equipment

Breaking Capacity Selection

The breaking capacity of the VF003 should always exceed the maximum potential short-circuit current at the installation point. Consider:

1. Installation location: Proximity to the main distribution board
2. Supply transformer size: Larger transformers can deliver higher fault currents
3. Cable impedance: Longer cable runs reduce available fault current

Installation Best Practices for the VF003 MCB

Mounting Instructions

1. The VF003 mounts securely on standard 35mm DIN rails (EN 60715) using the integrated fast clip device
2. Ensure sufficient space around the MCB for proper heat dissipation
3. Install in a vertical position with ON/OFF markings oriented correctly
4. Maintain minimum clearances as specified in installation guidelines

Wiring Guidelines

1. Use the appropriate cable size (up to 25 mm² or 18-4 AWG)
2. Tighten terminal screws to the specified torque (2.5 N·m or 22 In-lbs)
3. Strip conductors to the correct length before insertion
4. Check that all connections are secure before energizing

Testing and Commissioning

1. Visually inspect the installation for proper mounting and connection
2. Test the operation of the manual switch mechanism
3. Verify the isolation function by measuring across open contacts
4. Test the tripping function using appropriate test equipment

Maintenance and Troubleshooting

Regular Maintenance Checks

1. Visual inspection: Check for signs of overheating or damage
2. Manual operation test: Periodically toggle the switch to ensure smooth operation
3. Terminal tightness: Verify that all connections remain secure
4. 絶縁抵抗: Periodically measure the insulation resistance across open contacts

Common Issues and Solutions

Problem	Possible Cause	Solution
Frequent tripping	Overloaded circuit	Reduce the load or install higher rated MCB
	ショート	Identify and repair the fault
	Nuisance tripping	Consider changing to a more suitable trip curve
MCB won’t reset	Persistent fault	Locate and clear the fault before resetting
	Mechanical damage	Replace the MCB
Overheating	Loose connections	Tighten terminals to specified torque
	Overload	Reduce circuit load

Standards and Certifications

The VF003 miniature circuit breaker complies with multiple international standards:

• IEC/EN 60898-1: International standard for MCBs
• NF certification: French quality and safety standard
• UKCA approval: UK Conformity Assessed mark
• CE marking: European conformity certification

These certifications ensure the VF003 meets stringent quality and safety requirements for electrical protection devices.

環境への配慮

動作条件

The VF003 MCB is designed to operate reliably under the following conditions:

• Ambient temperature range: -5°C to 40°C (with daily average ≤35°C)
• Storage temperature range: -25°C to 70°C
• 汚染度：2
• 保護等級IP20

環境への影響

Modern electrical installations increasingly consider environmental factors:

• The VF003’s long mechanical and electrical life (20,000 and 10,000 cycles respectively) reduces replacement waste
• Energy limiting class 3 certification contributes to energy-efficient installations
• Compliance with RoHS and other environmental directives ensures minimal environmental impact

Accessory Options for Enhanced Functionality

The VF003 MCB can be complemented with various accessories to extend its functionality:

1. 補助接点: For status monitoring and integration with building management systems
2. Shunt release: Remote tripping capability for emergency shutdown
3. Under voltage release: Automatic disconnection during voltage dips
4. Alarm contacts: For remote indication of trip events

These accessories increase the versatility of the VF003, enabling integration into modern smart building systems.

Conclusion: Why the VF003 MCB is the Right Choice

The VIOX VF003 miniature circuit breaker combines superior protection capabilities with versatile configuration options, making it suitable for virtually any electrical installation requirement. With its NF certification, multiple trip curve options, and comprehensive range of current ratings, the VF003 delivers reliable, safe, and efficient circuit protection.

Whether you’re working on a simple residential installation or a complex industrial system, the VF003 MCB provides the performance, reliability, and safety features needed for today’s demanding electrical environments.

For more information about the VF003 miniature circuit breaker or to explore other VIOX electrical protection solutions, contact our technical support team or visit our website at viox.com.