EARU EACBDC Series DC Miniature Circuit Breaker Instruction Manual

1. Introduction

The EARU EACBDC-63/125 Series DC Miniature Circuit Breaker (MCB) is designed for the protection of DC distribution systems and electrical equipment. It provides essential overload and short-circuit protection for circuits with a rated current of 63A/125A or less and a direct current rating voltage of 1000V. Available in 1-pole (1P), 2-pole (2P), 3-pole (3P), and 4-pole (4P) configurations, these MCBs are suitable for a wide range of applications including electric, post, traffic, mining enterprises, and particularly photovoltaic (solar) systems.

Key Features:

Thermoplastic Shell: Features a full inlet, impact-resistant, recyclable, and self-extinguishing thermoplastic shell for enhanced safety and durability.
Super Safety U Tunnel Terminal: Ensures solid and reliable line connections, minimizing risks associated with loose wiring.
Original Air Flow Design: Effectively reduces temperature between adjacent circuit breakers, contributing to stable operation and extended lifespan.
Ergonomic Safety Handle: Classic original design for comfortable and secure operation.

2. Specifications

The following table details the technical specifications for the EACBDC Series DC Miniature Circuit Breakers:

Parameter	Value
Product Series	EACBDC
Product Characteristics	C type
Rated Voltage	DC 1000V
Pole Number	1P, 2P, 3P, 4P
Rated Current	6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A, 80A, 100A, 125A
Breaking Capacity (6A-63A)	4500A
Breaking Capacity (80A-125A)	10000A
Rated Breaking Capacity	6.0kA IEC60898 (0.5~63A), 6,10,15A IEC60947-2 (0.5~63A)
Function	Overload/short circuit protection
Mounting	Rail mounted
Product Certification	CE
Characteristic Curve	C
Max. Fuse Connectable	100AgL (>10kA)
Electrical Life	≥ 8000 times
Mechanical Life	≥ 20000 times
Selective Grade	3
Working Ambient Temperature	-10℃ ~ +40℃
Enclosed Protective Class	IP20

Dimensions:

3. Component Identification

Refer to the diagram below for identification of key components of the DC Miniature Circuit Breaker:

Labeled diagram of a 2P DC Circuit Breaker — Figure 3: Key components of the EACBDC Series DC MCB. Includes Brand (EARU), Model Number (EACBDC-63), Rated Current (C63), Window Indication, Wiring Diagram, Operating Handle, and Fastening Screws.

Brand: EARU
Model Number: EACBDC-63 (or EACBDC-125)
Rated Current: e.g., C63 (63A)
Window Indication: Visual indicator for ON/OFF status.
Wiring Diagram: Printed on the device, showing connection points.
Operating Handle: Used to manually switch the breaker ON or OFF.
Fastening Screws: For securing wiring connections.

4. Installation

Installation of the EACBDC Series DC Miniature Circuit Breaker should be performed by a qualified electrician in accordance with local electrical codes and standards.

4.1 Mounting

The circuit breaker is designed for rail mounting. Ensure the DIN rail is securely installed in your distribution box or enclosure.

3P EACBDC-63 mounted on DIN rail — Figure 4: A 3-pole EACBDC-63 circuit breaker mounted on a DIN rail.

2P EACBDC-63 mounted on DIN rail — Figure 5: A 2-pole EACBDC-63 circuit breaker mounted on a DIN rail.

4.2 Wiring

Before wiring, ensure all power sources are disconnected to prevent electrical shock.

Connect the incoming DC positive (+) and negative (-) wires to the upper terminals of the circuit breaker as indicated by the wiring diagram on the device.
Connect the outgoing DC positive (+) and negative (-) wires to the lower terminals of the circuit breaker.
For multi-pole breakers (2P, 3P, 4P), ensure correct polarity and phase connection for each pole.
Tighten the fastening screws securely to ensure a solid electrical connection.

Wiring diagram on a 2P DC Circuit Breaker — Figure 6: Wiring diagram indicating input at the top and output at the bottom terminals.

5. Operation

The EACBDC Series DC Miniature Circuit Breaker is designed for simple and reliable operation.

5.1 Switching On/Off

To switch the circuit breaker ON, push the operating handle upwards. The window indicator will display RED, signifying that the circuit is closed and operating normally.

To switch the circuit breaker OFF, push the operating handle downwards. The window indicator will display GREEN, signifying that the breaker is open and the circuit has stopped running.

Window Indicator Operation Display for DC Circuit Breaker — Figure 7: Window indicator shows GREEN when the breaker is OFF (circuit open) and RED when the breaker is ON (circuit closed).

5.2 Automatic Tripping

In the event of an overload or short circuit, the breaker will automatically trip to the OFF position, indicated by the GREEN window. This protects the circuit and connected equipment from damage.

Video 1: Demonstration of the circuit breaker's manual ON/OFF operation and mounting mechanism.

6. Maintenance

Regular maintenance helps ensure the longevity and reliable operation of your DC Miniature Circuit Breaker.

Visual Inspection: Periodically inspect the circuit breaker for any signs of physical damage, discoloration, or loose connections.
Cleaning: Keep the breaker clean and free from dust and debris. Use a dry, non-abrasive cloth for cleaning. Do not use liquids or solvents.
Connection Check: Ensure all wiring connections remain tight and secure. Loose connections can lead to overheating and potential hazards.
Functional Test: Occasionally, manually switch the breaker OFF and then ON to ensure the mechanism operates smoothly.

Always disconnect power before performing any maintenance or inspection.

7. Troubleshooting

This section addresses common issues you might encounter with your DC Miniature Circuit Breaker.

7.1 Breaker Trips Frequently

Overload: The connected load might be drawing more current than the breaker's rated capacity. Reduce the load or consider a higher-rated breaker (ensure it's appropriate for your wiring).
Short Circuit: A short circuit in the wiring or connected equipment will cause the breaker to trip immediately. Inspect the wiring and equipment for faults.
Ground Fault: In some systems, a ground fault can also cause tripping. Check for insulation damage.

7.2 Breaker Does Not Reset

Persistent Fault: If the underlying overload or short circuit condition is still present, the breaker will not reset. Identify and clear the fault first.
Internal Damage: If there is no apparent fault and the breaker still won't reset, it might be internally damaged and needs replacement.

7.3 No Power to Circuit

Breaker OFF: Check if the breaker handle is in the OFF position (GREEN indicator). Switch it ON (RED indicator).
Loose Connections: Inspect wiring terminals for loose connections.
Upstream Issue: Check other protective devices (e.g., main breaker, fuses) upstream in the electrical system.

8. User Tips

Correct Pole Selection: When integrating into systems like solar PV, carefully select the correct number of poles (1P, 2P, 3P, 4P) based on your system's voltage and current requirements. For example, a 2-pole breaker might be suitable between a 12V battery and an inverter, while a single-pole might be used for individual solar panel strings.
Match Current Rating: Always ensure the chosen current rating (e.g., 6A, 10A, 32A, 125A) is appropriate for the maximum expected current of the circuit it protects. An undersized breaker will trip frequently, while an oversized one may not provide adequate protection.
Professional Installation: For complex DC systems, especially those involving high voltages like 1000V, it is highly recommended to have installation and wiring performed by a certified professional.
Observe Indicators: Pay attention to the window indicator (RED for ON, GREEN for OFF) for quick visual confirmation of the breaker's status.

9. Warranty and Support

For warranty information, technical support, or service inquiries, please contact your original point of purchase or the EARU customer service department. Ensure you have your product model number (EACBDC) and any relevant purchase details available when contacting support.