The lightning energy absorption in the power surge protector is mainly a zinc oxide varistor and a gas discharge tube. The zinc oxide varistor is a voltage-limiting protection device. When there is no pulse voltage, it exhibits a high-resistance state. Once the pulse voltage is responded, the voltage is immediately limited to a certain value, and the impedance is abruptly changed to a low-resistance state. Compared with the gas discharge tube, its biggest advantage is that when it absorbs the pulse voltage, the residual voltage is higher than the working voltage, it will not cause a short circuit of the power supply, and no freewheeling will occur. The zinc oxide varistor has a faster response time than the gas discharge tube. The breakdown voltage of the gas discharge tube is very sensitive to the rising rate of the pulse voltage. The faster the voltage rise rate, the higher the ignition voltage and the faster the response time. It is possible to correctly select the two types of components, such as varistor and gas discharge tube, and use their respective advantages to combine the power supply arresters, and the overall performance is relatively good. Zinc oxide varistor is required in the power supply arrester and has excellent energy withstand characteristics. The energy withstand characteristic is mainly described by three indicators: rated lightning impulse current, maximum lightning impulse current and energy tolerance. These characteristics are sensitive to zinc oxide. The surface area of ​​the resistor is related to the heat dissipation conditions of the component. The same type of varistor, due to different manufacturers' manufacturing processes and raw material formulations, their energy tolerance will vary greatly. The gas discharge tube has a strong ability to withstand large energy shocks, but in the specific use, since the residual voltage of the gas discharge tube during discharge is extremely low, which is similar to the short circuit state, it cannot be used alone in the power supply arrester, and the gas discharge tube is used. The flow resistance is related to the pipe diameter. The larger the pipe diameter, the better the flow resistance. The quality problem of the gas discharge tube is mainly characterized by chronic air leakage, reliability problem of long-term use (that is, the DC breakdown voltage value is shifted after suffering multiple lightning impulses), and the photosensitivity effect and dispersion are large. Although the domestic gas discharge tubes have been greatly improved in recent years, the quality is gradually improving, but the overall quality problems still exist, especially the reliability problems and chronic air leakage problems. Therefore, the choice of imported brand-name gas discharge tube in the power supply arrester should be the first choice, and the diameter of the gas discharge tube is better than Ф8mm. The choice of capacitors and thermal fuses in power surge protectors is also important. The power supply arrester has been working in the power grid for a long time. There are many cases in which the power supply arrester is damaged due to the quality problem of the capacitor. Therefore, the voltage withstand selection of the capacitor is very important, especially the impulse withstand high voltage. In contrast, foreign products are better than domestic products, Hitachi, OKAYA's capacitor quality is good. The function of the thermal fuse in the lightning arrester is that when the lightning current exceeds the maximum capacity of the lightning arrester, the fuse can be disconnected due to the overcurrent, and the fuse can be disconnected due to the temperature rise of the zinc oxide varistor due to overcutting. It acts as both overcurrent and temperature protection. Due to the normal operating conditions of the power supply arrester, the current is very small, only in the case of lightning shock or pulse voltage shock, under the transient conditions, it is different from the conventional hot-melt fuse, so the power supply arrester Hot melt fuses should have unique properties, ie, blow characteristics under transient conditions. Product Features
5. The pre-opened silica gel lid allows the Pipette tip or probe to enter the hole without damaging the lid.
6. After the third party inspection, no RNA/DNA enzyme contamination
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1. The product is easy to open and close, which can effectively seal deep well plates, sample tubes, etc., which is convenient for operation and saves time.
2. Good airtightness can prevent the volatilization of various solvents.
3. Tolerate a wide temperature range, suitable for various experiments.
4. Resistant to chemical corrosion and used for low-temperature storage.
7. It can be used on automated machines, and the product size conforms to the SBS standard
8. It can be used with stickers, silica gel, and sealed without leakage. 96 round-hole silica gel and 8-hole silica gel strip with matching sealing plate
9. Good flatness, can be transported long distance after sealing with heat sealing film
10. The products are produced and packaged in a 100,000-class dust-free workshop, and the product quality is stable
11. Alphabetical sorting and cut corner marking make the storage and collection of samples more convenient and faster.
12. Each package has an independent article number and batch number identification, which is convenient for quality tracking and traceability