TOMZN 2P DC MCCB 1500V Molded Case Circuit Breaker

1. Introduction

The TOM7Z DC Circuit Breaker is designed for use in DC electricity power lines, offering robust protection for various applications including PV solar systems, wind power installations, hydropower setups, electric vehicles, and other DC power supply devices. This circuit breaker features a high breaking capacity of up to 65kA and is non-polarized, allowing for flexible input connections from either the top or the bottom while maintaining normal operation.

This manual provides essential information for the safe installation, operation, and maintenance of your TOMZN DC MCCB.

2. Safety Information

Always prioritize safety when working with electrical systems. Improper installation or use can lead to serious injury or damage. Please observe the following:

• Ensure all power sources are disconnected before installation or maintenance.
• Only qualified personnel should perform electrical installations.
• Verify the voltage and current ratings of your system match the circuit breaker's specifications.
• The circuit breaker features safety insulation and a double insulation design to prevent damage and ensure user safety.
• Do not bypass or tamper with the circuit breaker's protective mechanisms.

3. Product Overview and Features

The TOMZN DC MCCB is engineered for reliable performance and ease of use. Key features include:

• Large Handle Design: High-hardness operating handle, resistant to compression and wear, ensuring safety and durability.
• Dual Protection & Arc Isolation: Innovative rubber barriers and terminal caps effectively isolate arcs, protecting wiring terminals and ensuring stable operation in high-voltage, high-current environments.
• Stable Performance: Utilizes mature current limiting technology to suppress fault currents, greatly reducing impact on components and electrical equipment.
• Instant Disconnect: Disconnects quickly (within 0.1 seconds) upon overload or short circuit to protect circuits and equipment.
• Reliable Arc Extinguishing: Optimized design with a large volume arc extinguishing chamber for reliable breaking of fault currents.
• Double Insulation: Insulated internal structure for enhanced safety and convenient accessory installation.
• High-Quality Contacts: High-conductivity contacts capable of carrying large currents efficiently.

Figure 3.1: Four key advantages ensuring quality and safety.

4. Specifications

Refer to the table below for detailed product specifications:

Figure 4.1: Product Information Table

Figure 4.2: Product Dimensions

5. Setup and Installation

The TOMZN DC MCCB is designed for easy wiring and installation. However, due to the high voltage and current involved, professional installation is highly recommended.

5.1 Component Identification

Figure 5.1: Key Components

• Trademark: TOMZN branding.
• Parameter Information: Label detailing specifications (e.g., voltage, current, breaking capacity).
• Handle Switch: Used to manually turn the circuit breaker ON or OFF.
• Test Button (PUSH TO TRIP): Used to manually trip the circuit breaker for testing its functionality.

5.2 Wiring Instructions

The TOM7Z circuit breaker is non-polarized, meaning the input can be connected from either the top or the bottom. Ensure all connections are secure and properly insulated.

Figure 5.2: Wiring Diagram for Battery and Load

Figure 5.3: Wiring Diagram for Solar PV System

General Wiring Steps:

1. Mount the circuit breaker securely in an appropriate enclosure.
2. Connect the positive (+) and negative (-) DC power lines to the designated terminals. Refer to the wiring diagrams (Figures 5.2 and 5.3) for specific application examples.
3. Ensure all terminal screws are tightened to the manufacturer's specifications to prevent loose connections and overheating.
4. Utilize the arc isolation solution by properly installing rubber barriers and terminal caps if provided, to enhance safety and protect wiring.
5. Double-check all connections for correctness and security before applying power.

6. Operating Instructions

6.1 Turning ON/OFF

• To Turn ON: Push the handle switch upwards to the 'ON' position.
• To Turn OFF: Push the handle switch downwards to the 'OFF' position.

Figure 6.1: Handle Switch in OFF Position

6.2 Overload and Short Circuit Protection

In the event of an overload current or short circuit, the circuit breaker will automatically disconnect within 0.1 seconds to protect your electrical system and connected equipment. The handle switch will move to the 'OFF' or tripped position.

Figure 6.2: Instant Disconnect Feature

6.3 Testing the Circuit Breaker

To test the tripping mechanism, press the red 'PUSH TO TRIP' button located on the front of the circuit breaker. This will manually trip the breaker, moving the handle to the 'OFF' position.

6.4 Resetting After a Trip

If the circuit breaker trips due to a fault:

1. First, identify and resolve the cause of the overload or short circuit.
2. Once the fault is cleared and the circuit is normal, you can reset the circuit breaker by pushing the handle switch upwards to the 'ON' position.

7. Maintenance

Regular maintenance helps ensure the longevity and reliable operation of your circuit breaker.

• Visual Inspection: Periodically inspect the circuit breaker for any signs of physical damage, discoloration, or loose connections.
• Cleaning: Keep the circuit breaker free from dust and debris. Use a dry, non-abrasive cloth for cleaning. Do not use liquids or solvents.
• Terminal Check: Ensure all wiring terminals remain tight. Re-tighten if necessary, ensuring power is off before doing so.
• Functionality Test: Periodically test the trip mechanism using the 'PUSH TO TRIP' button to ensure it is functioning correctly.

8. Troubleshooting

If you encounter issues with your TOMZN DC MCCB, consider the following troubleshooting steps:

• Circuit Breaker Trips Frequently: This indicates an ongoing overload or short circuit in the protected circuit. Immediately investigate the connected load and wiring for faults. Do not repeatedly reset the breaker without addressing the underlying issue.
• Circuit Breaker Does Not Reset: Ensure that the fault condition (overload or short circuit) has been completely cleared. If the fault persists, the breaker will not reset. If no fault is present and it still won't reset, the breaker may be damaged and require replacement.
• No Power to Load (Breaker ON): Check all wiring connections for looseness or damage. Verify that the power source to the breaker is active. If the breaker's internal contacts are damaged, it may not conduct power even when in the 'ON' position.
• Overheating: If the circuit breaker or its terminals feel excessively hot, it could indicate an overload, loose connections, or an undersized breaker for the application. Disconnect power and investigate immediately.

For persistent issues or if you are unsure about any troubleshooting step, consult a qualified electrician.

9. User Tips

• Proper Sizing: Always ensure the circuit breaker's rated current matches or exceeds the maximum expected load of your DC system, but is appropriately sized to protect the wiring.
• Environmental Conditions: Operate the circuit breaker within its specified operating temperature range (-5~40℃) to ensure optimal performance and lifespan.
• Professional Consultation: For complex solar PV or high-current DC installations, it is always advisable to consult with a certified electrician or solar professional.
• Documentation: Keep this instruction manual in a safe and accessible place for future reference.

10. Warranty and Support

For warranty information, terms, and conditions, please refer to the documentation provided at the time of purchase or contact the seller directly. Keep your purchase receipt as proof of purchase.

For technical support or inquiries, please contact TOMZN Official Store or your authorized distributor.