1. Core definition of dual-circuit overload protection switch

The dual-circuit overload protection switch is an electrical safety device featuring independent protection for two circuits. By integrating two sets of independent overload detection and tripping mechanisms within the same switch body, it monitors and protects two electrical circuits separately against overload conditions. When any one of the circuits experiences overload conditions such as current overload or abnormal temperature, the protection mechanism of the corresponding circuit will act independently to cut off the power supply to the faulty circuit, while ensuring continuous power supply to the other normal circuit, achieving the protective effect of "fault isolation and safety redundancy".

II. Core working principle

Its working logic is based on the thermal effect of current and bimetallic strip deformation technology (mainstream technology path), combined with dual-loop independent control design:

1. Two electrical circuits are respectively connected in series with independent bimetallic strip components to monitor the current magnitude in the circuits in real time;

2. When the current in a certain circuit exceeds the rated value (i.e., overload), the thermal element generates heat due to the thermal effect of current, causing the bimetallic strip (formed by bonding two metals with significantly different expansion coefficients) to bend and deform;

3. The deformed bimetallic strip activates the trip mechanism, quickly disconnecting the contacts of the faulty circuit and preventing the overload current from continuing to pass through (to avoid overheating of the circuit, damage to equipment, and even the risk of fire);

4. The thermal element of the other normal circuit has not reached the action threshold, so the contact remains closed to ensure normal power supply to related equipment and avoid losses caused by overall power outage.

III. Key Technical Features and Advantages

1. Dual-circuit independent protection: The protection mechanisms of the two circuits are physically isolated and do not interfere with each other. The tripping of the faulty circuit does not affect the operation of the normal circuit, enhancing power supply continuity (especially suitable for scenarios sensitive to power outages);

2. Dual protection dimensions: It monitors both "overcurrent" (current exceeding limits) and senses "overtemperature rise" (abnormal temperature of circuits or equipment). Even when the current does not exceed the limit but the temperature is abnormal, protection can still be triggered, meeting the dual important requirements for electrical safety stipulated in the new national standard GB/T 14048.11-2024;

3. Precise adjustable setting: The overload protection threshold (trip current) of each circuit can be independently set (such as 10A, 16A, 25A, etc.), adapting to the power consumption needs of different loads and providing stronger compatibility;

4. Quick reset design: After the overload fault is resolved, the circuit power supply can be restored through manual or automatic reset functions, with convenient operation and no need to replace components (unlike the one-time protection of fuses);

5. High withstand capability: The core components comply with the international standard IEC 60947-6-1, possessing strong short-circuit withstand capability and higher stability in complex power grid environments.

IV. Typical application scenarios (aligning with the research and development direction stated in the acquisition announcement)

1. Household electrical appliances: Sockets with four or more holes and extension sockets that comply with the new national standard GB 2099.7—2024, ensuring electrical safety for different sets of plug holes in the socket (for example, a kitchen socket connected to both a refrigerator and a microwave oven, preventing overall power outage caused by overload of a single device);

2. Industrial control field: In industrial assembly lines and motor control circuits, the main drive circuit and auxiliary control circuit are separately protected to prevent local overload from affecting the operation of the entire production line;

3. Electronic equipment field: In PC power supplies and server power supplies, avoid overloading high-power components that may damage the power supply or motherboard;

4. Key facility areas: In scenarios where high power supply continuity is required, such as communication equipment rooms, medical equipment, and fire protection systems, dual-circuit protection can reduce the risk of downtime caused by a single circuit failure, meeting the requirements of the "Essential Safety Level Improvement Action".

V. Core differences from single-circuit overload protection switches

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