Due to the small resistance value of the fuse itself, and we hope that the smaller the better, the voltage drop at both ends of the fuse is very small, much smaller than the rated voltage of the fuse. Therefore, when the fuse operates normally, the rated voltage has little practical significance. The true significance of the rated voltage of a fuse lies in its safety performance. As a safety component, a fuse must be ensured to be safe during normal operation, during protective actions, and at any time after the melt melts. During and after the melt melts, the rated voltage of the fuse is of great significance. The unsafe factor when a fuse blows comes from the energy released by overcurrent, and the magnitude of this energy depends on the product of current and voltage. The maximum current to ensure the safety of the fuse is the rated breaking capacity, and the maximum voltage is the rated voltage. If the rated voltage of the fuse is less than the circuit voltage, it may cause uns
As a safety component, in addition to its performance requirements, a fuse must also have strict safety requirements. The breaking capacity of a fuse is an important indicator reflecting the safety performance of the fuse. Its specific meaning is: the maximum short-circuit current that the fuse can withstand without any unsafe phenomena during the process of breaking the circuit. The unsafe phenomena here include - continuous arcing, smoking, spraying, splashing Burning, explosion, etc. Tubular fuses can be classified into high breaking (1500A), low breaking (35A or 10In), and enhanced breaking (150A) types based on their breaking capacity. The breaking capacity of chip fuses is generally between 30-60A, which is often overlooked or misunderstood by users or confused with the fusing characteristics of fuses, The correct understanding of the breaking capacity of a fuse should be that the extreme maximum current in the event of a short circuit in the protected circuit cannot exceed t
The disposable slow blow fuse 0402 is a very compact patch fuse with a size of only 1 * 0.5mm, making it the smallest fuse in the patch fuse. The BFS0402 series of BDT-FUSE brand can be selected for the 0402 disposable slow blow fuse. This series is a surface mount fast melting thin film fuse. The ultra small package (0402 specification) is very suitable for secondary protection of circuits and is suitable for applications with limited space, such as handheld portable electronic devices. This series is 100% lead-free and meets the requirements of the RoHS directive. The BFS0402 series can correspond to a working current range of 0.25A, 0.375A, 0.5A, 0.75A, 1A, 1.25A, 1.5A, 1.75A, 2A, 2.5A, 3A, 3.5A, 4A, 5A, and a working voltage of 32V. The interruption rating under 32VDC is 35A. BFS0402 provides maximum protection for sensitive circuits, and the fuse can activate protection within 5 seconds under a 200% overload condition.
The 0467 series patch fuse is a disposable fuse, and the fast melting surface mount fuse (SMF) is a ultra small (0603 size) thin film device designed for secondary protection of circuits used in space limited applications such as handheld portable electronic devices. This series is 100% lead-free and meets the requirements of the RoHS directive. The rated current range of the 0467 series patch fuse is 0.25A-5A, the rated voltage is 32V, the working environment temperature is -55 ℃ to 125 ℃, the cold resistance is 0.0089-0.5650, and the voltage drop is 61.20-158.56. The main material of this series: The fuse body is mainly an advanced high-temperature substrate, with 100% tin nickel on copper at both ends and a conformal coating on the outer layer. This series works normally in an environment of -55 ℃~90 ℃, with a specification size of 1.6mm * 0.8mm and packaging method of 8mm mm tape and reel, with 5000 pieces per roll. 0467 Chip Fuse Parameter Table The 0467 series fuse models
The PTC1812 self recovery fuse is a lead-free surface mount self recovery fuse with a volume of 45mm * 32mm patch fuse. Among the self recovery patch fuses, the PTC1812 series has a moderate volume and is suitable for use on many electronic product motherboards, occupying just the right amount of space. The voltage range is 6V-60V, and the current has specifications such as 100MA-4A (please refer to the 1812 series specifications for details). The most commonly used models are PTC1812-010, PTC1812-050, PTC1812-075, PTC1812-260, and PTC1812-300. PTC1812 self recovery fuse can be applied to plug and play protection devices for USB peripheral devices, hard drives, optical drives, motherboards and peripheral devices, PDA/digital cameras, and game console ports.
1. What is the voltage value at both ends of the series connected pptc component in the circuit? 2. What is the average current value of the circuit flowing through the pptc component under normal working conditions? 3. When a circuit experiences a load short circuit, how much will the fault current in the circuit increase, causing damage to the circuit or other components in the circuit? When the circuit load and fault current increase to 10 amperes, the circuit or components in the circuit are damaged, which affects the normal operation of the circuit. Therefore, it is necessary to quickly protect the circuit with pptc components, and the current value at this time is the limit current value. 4. What is the ambient temperature of the circuit? (Because pptc components belong to positive temperature coefficient thermistors and are affected by environmental temperature) 5. How long does the circuit work? (Is the circuit working continuously for a long time (more than 4 hours) or