ฟังก์ชั่นของฟิวส์ไฟฟ้าเซรามิกและแก้ว

The following is a core technical analysis and selection guide for ceramic and glass electric fuses, compiled from authoritative information from multiple sources:

ฉัน. Core working principle‌
‌Fusing mechanism‌
‌Joule heat effect‌: When the current is overloaded, the heat generated by the conductor Q=0.24I2RtQ=0.24I2Rt exceeds the heat dissipation capacity, and the temperature rises to the melting point and melts.
‌Fusing curve‌:
1.3 times the rated current: melting time>1 ชั่วโมง
1.6 ครั้ง: melting time<1 ชั่วโมง
8~10 times: instantaneous melting

‌Core function‌
Connected in series in the circuit, it cuts off abnormal current (overload/short circuit) by self-fusing to protect the equipment from burning or fire.

‌II. Key parameters and classification‌
‌1. Current/voltage specifications‌

Parameters‌	คำนิยาม	Selection rules
จัดอันดับปัจจุบัน (ใน)	Maximum current value for continuous safe operation	Needs to be slightly larger than the circuit operating current (E.G. 25A for a 20A circuit)
แรงดันไฟฟ้าที่ได้รับการจัดอันดับ (และ)	The highest voltage that can be safely isolated after the fuse is blown	≥circuit operating voltage

2. Classification of fuse characteristics‌

‌Type‌	ความเร็วในการตอบสนอง	‌‌Applicable scenarios	‌ Identification‌
Fast blow type	Millisecond level	Precision electronic equipment, semiconductor protection	FF（Fast Blow）
Slow blow type	Second level	Motor start, surge current circuit (such as car lights)	FM（Slow Blow）

3. Structural type‌

‌ พิมพ์	‌คุณสมบัติ	Typical applications
Glass tube fuse	ต้นทุนต่ำ, visible fuse status	Small household appliances, อะแดปเตอร์พลังงาน
Ceramic tube fuse	High breaking capacity, strong arc extinguishing	Industrial equipment, electric vehicle battery packs
ฟิวส์ SMD	การย่อขนาดเล็ก, SMT process	Mobile phones, laptop motherboards
Automotive chip fuses	Standardized color coding (such as red 10A, blue 15A)	Vehicle electrical system

III. การเลือกและใช้คะแนน ‌

‌Current matching‌
Calculation formula: ‌Rated current ≥ circuit operating current × 1.25‌ (safety margin reserved).
Avoid replacing low-current models with high-current fuses, otherwise the protection function will be lost.

aptability การปรับสภาพแวดล้อม ‌
High temperature environment: select high-temperature resistant ceramic material (＞100℃ working conditions).
Vibration scenario: automotive fuses require impact-resistant structures (such as plug-in/bolt fixing).

‌Fault prevention‌
‌Poor contact‌: Fuse terminals oxidize and cause abnormal fusing, and regular inspection and tightening are required.
‌Pulse current‌: Slow-fuse type must be selected for scenarios such as motor starting.

‌Replacement specification‌
After fusing, it must be replaced with the same specification, and copper/iron wire short-circuiting is prohibited.

4. Typical failure causes

Fault phenomenon	‌Main cause	‌Solution‌
Frequent fuse	Load overload, short circuit or fuse rated current is too small	Check load power, Recalculate selection
Abnormal heating without fuse	Contact resistance is too large or poor quality fuse	Clean terminals and replace compliant products
Fuse when powered on	Short circuit in the circuit (such as line damage)	Check short circuit point and replace fuse after repair

5. Special type expansion ‌
‌Temperature fuse‌: responds to overheating rather than overcurrent, used to prevent overheating of electric irons and chargers.
‌Self-resettable fuse‌: impedance increases sharply after overcurrent, automatically resets after cooling, suitable for USB port protection.

‌Note‌: Fuses must be used in conjunction with circuit breakers, the former protects equipment, and the latter protects lines; high breaking capacity fuses should be used in ultra-high voltage scenarios (>600วี).