With the expansion in the use of DC power systems and increased need for system maintenance, the development of measurement devices for maintenance requires high stability. Of the different kinds of DC current measurement devices, the single-shot measurement device causes the input signal of the current measuring unit to initially generate a high inrush current. The high inrush current flows into the signal processor of the meter, shortening the life of the internal fuses and causing failure. Therefore, in this study, the I2t value for increasing the durability of the fuse is designed using the available wire diameter. Operating characteristics for 210~400% over-current of the rated current, which is relatively low over-current, are realized by the plating of low melting tin metal. As a result, a method of designing a fuse element for a DC power supply, which improves the safety of the DC current measurement device by blocking the failure caused by the inrush current, is presented.
In this paper, we prepared miniature fuse fabricated with carbon nanotube (CNT) fiber for the use of low rated current under 1 A and high speed operation under 4ms. CNT fuses were fabricated in the form of universal modular fuse (UMF) with different diameter of CNT fibers defined by multiplying the CNT threads. Electrical properties of the CNT fuses were measured such as resistance, rated current, and operation time with current. Resistance of the CNT fuse decreased and rated current increased with the diameter of the CNT fuses, respectively. Consequently, the operation time with current increased with the diameter of the CNT fuses. The CNT fuses fabricated in this work had broad range of low rated current from 0.05 to 1.25 A by multiplying the CNT threads. Operation time was measured about 3.6ms which was applicable to the UMF.
Recently, inverter control systems have attracted immense attention to increase the energy efficiency. However, such systems use repeated on/off high currents for linear operation control, instead of the prevalent step variable current control method. Hence, there arise concerns of personal and property damage, especially due to the durability, explosive characteristics, and operating speed of the fuse, which is responsible for safety and is one of the internal components using current control. Therefore, in this paper, we propose an IEC60127-4 SMD sub-miniature fuse, consisting of Ag-Cu alloys and ceramic powder for arc soothing. The IEC60127-4 SMD sub-miniature fuse has high durability and cut-off capacity, and operates safely in dangerous circumstances caused by the inverter control system.
High-capacity secondary batteries can cause explosion hazards owing to microcurrent variations or current surges that occur in short circuits. Consequently, complete safety cannot be achieved with general protection that is limited to a mere current fuse. Hence, in the case of secondary batteries, it is necessary for the protector to limit the inrush current in a short circuit, and to detect the current during microcurrent variations. To serve this purpose, a fuse can be employed for the secondary battery protection circuit with current detection. This study aims at designing a protection device that can stably operate in the hazardous circumstances associated with high-capacity secondary batteries. To achieve the said objective , a detecting fuse was designed from an alloy of low melting point elements for securing stability in abnormal current states. Experimental results show that the operating I-T and V-T characteristic constraints can be satisfied by employing the proposed current detecting self-contained low melting point fuse, and through the resistance of the heating resistor. These results thus verify that the proposed protection device can prevent the hazards of short circuit current surges and microcurrent variations of secondary batteries.
We investigated the dielectric relaxation properties 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics with CuO addition. With increasing CuO addition, the lattice parameter was increased by substitution of small amount Cu2+ ion in B-site of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics. Also the grain size and the maximum dielectric constant of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics was decreased with increasing amounts of CuO addition. Moreover, the diffused phase transition properties (γ) of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics was increased by compositional fluctuation with increasing of CuO amount, changed from 1.45 at 1 wt% CuO addition to 1.94 at 7 wt% CuO addition.
For the semiconductor device safety from over current in the digital electronic circuit systemmust be surely designed that it`s surface mount type micro fuse device. In this paper, We has analysedto the fusing character of micro fuse as a function changed thickness of thermosetting ink epoxy. To thechange of thermosetting ink epoxy thickness with in production lot, in the electrically character (fusingtest in the 2 multiple over current and 10 multiple over current, surface temperature test in the 1.25multiple over current) of micro fuse has been tested. According to the electrically character result,changed thickness of thermosetting ink epoxy in designed micro fuse withheld direct effect in both endresistance changes. Also, because high thermal energy in the micro fuse test of over current wasoccurred to effect such as thermal runaway and explosion. Therefore, screen printing process in thedesign of micro fuse using thermosetting ink epoxy is very important for production quality improvement.
In this paper, we have researched semiconductor optical filters to solve the problem of the high failure rate that are recognize bad of financial account, jam of financial account and the ATM service interruption due to failure of accurate location information among the operation of the ATM (automatic teller machine) systems. A semiconductor optical filters that have high resolution and less diffuse, high transmittance are able to detect the information of financial account surface accurately. Therefore, it is a stable filter that is able to minimize the incidence of disability. In this paper, we drew the determinants by element for implement an excellent semiconductor optical filters. Based on this, we had to be able to implement the semiconductor optical filter that is able to be mounted on the actual ATM system through future studies.