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Surge Voltage and Lightning Protection for Household Electrical Appliances I. The necessity of surge protection for home appliances: Typical households own one or more of the following electrical appliances: televisions, refrigerators, VCDs, DVDs, home theaters, Hi-Fi systems, home computers, telephones, air conditioners, satellite TV receivers, vacuum cleaners... All of these appliances require electricity, which means that their power supply lines run from outside the house inside. Among them, televisions, home theaters, Hi-Fi speakers, and satellite TV receivers have power cables as well as antenna signals or cable signal lines. Home computers (with Internet access) and telephones have power cables and communication signal cables. Please refer to the diagram below; these externally connected wires may be struck by lightning at some point, transmitting the surge voltage from the lightning strike into the house ； Furthermore, when lightning occurs within a range of 1000 meters, the sudden large current generated by the lightning results in strong electromagnetic pulse radiation. The electrical appliances inside the house, the antenna connections, the power supply circuits, the cable TV/VOD lines, the communication lines, as well as the comprehensive grounding system – all of these are susceptible to surge voltages (also known as induced lightning). Therefore, protection against lightning strikes is essential in areas where lightning is frequent. Of course, lightning is just one type of surge voltage; there are many other causes of surge voltages as well. For example, surge voltages are generated when the compressor of a refrigerator starts or stops, and surge voltages also occur when fluorescent lamps and energy-saving lamps are turned on or off... and so on. These **small surges in voltage can affect electrical appliances. Very high surge voltages can directly damage electrical appliances, while lower surge voltages can disrupt the circuits of such appliances, causing changes in their originally set parameters and resulting in soft faults such as excessive noise and blurred images. Of course, over time this can lead to fatal damage to the electrical appliances. We often say that things these days are getting worse and worse. Radios from the 1950s or 1960s that cost just a few dozen dollars still work fine today, but the stereo system I bought for several thousand dollars last year is starting to produce more and more noise. It seems that home appliances these days aren’t as durable as they used to be! Why? 1. Transistors are becoming smaller and smaller these days, with thousands of them integrated on a single substrate. As a result, the distance between them becomes increasingly smaller, and their ability to withstand sudden voltage surges decreases. The surge voltage on the lines is also causing increasing damage to components. 2. Nowadays, electrical appliances operate at lower voltages, resulting in less energy consumption. It turns out that surges that are not sufficient to have an impact appear to have high voltages and large amounts of energy when compared to the very low operating voltage and power consumption. 3. Modern household appliances are becoming increasingly automated and intelligent, and their prices are rising as well; therefore, the importance of surge protection is also growing. 4. There are many sources of surge voltages. Electrical appliances with inductive or capacitive loads, such as refrigerators, air conditioners, vacuum cleaners, fluorescent lamps, energy-saving lamps, microwave ovens, and rice cookers, not only cause interference through electromagnetic radiation but also feed back into the power supply circuit, thereby interfering with and damaging nearby electrical devices. 5. Environmental damage! Due to pollution, there is an increase in dust in the air; the friction between these dust particles leads to an increase in electrical charge in the air, which results in more thunder and lightning! So... there’s no need to say more about it. Then, how does surging voltage affect household electricity use, and in what aspects? 1. Surges disrupt the original electrical parameter balance of household appliances; therefore, from time to time, they may seem less efficient than new ones. 2. Surge damage or deterioration of household appliance components: Continuous impact and aging lead to a decline in the performance of electronic components. Sometimes it causes soft failures; it is difficult to identify the cause and hard to repair. If a surge damages household appliances in one go, it may be the cumulative effect of multiple small surges, or it could be a single large surge (such as a lightning strike) that directly renders the equipment unusable. Often at this time, the electrical appliance isn’t just faulty in one area – there could be many problems! Repairing is not as good as replacing. 3. Casualties caused by surges: Reports of people being injured by lightning strikes are common in the newspapers. On the other hand, the aging of the electrical insulation layer caused by continuous surge voltages leads to the casing becoming charged, which in turn results in an even greater number of electric shock accidents! The following diagram illustrates the damage caused by surges to electrical appliances: Electrical appliances without surge protection – normal, brand new, 100% of usage time; operating condition of such appliances. Electrical appliances with surge protection – operating condition and time curve of those appliances. There is a sense of performance decline; performance drops to the point where the appliance can no longer function properly. Normal operation period, abnormal operation period. Electrical appliances without surge protection – complete failure of the appliance. They have a shorter service life, and experience frequent minor issues during an abnormal operation period (referred to here as a \"useless period\"); moreover, their total service life is shorter than that of appliances with surge protection. Moreover, during the period of inefficiency, continuous repairs or other adjustments may be necessary, indirectly increasing the usage costs. If no surges occur on the circuit, or if surge protection is applied to the electrical devices, these devices will age as shown by the blue lines in the diagram, allowing them to operate normally for as long as possible; it is only when the device’s service life comes to an end that it enters a period of limited functionality. Based on our understanding of the sources and hazards of surge voltages, we can protect household appliances in the manner shown in Figures 1 and 2. For information on related products, please visit http://www.asp.com.cn. The installation method is illustrated in the figure below: DS98 – to be installed before the household power inlet’s leakage circuit breaker or air switch; N Ph PE – for use in small switch boxes; for lighting, it is used in the wiring room; for other applications… Warning signs: The A6 series includes A6.Home, which is installed before electrical appliances; A6.TV, which is installed before televisions; A6.NET, which is installed before home computers; A6.HiFi, which is installed before home theaters or HiFi equipment. ASP2000 should be installed before the MODEM, with the ground wire connected to the mounting screws of the chassis. Power supply, cable TV or outdoor antenna, telephone line or ISDN. For Ds98 A6.Home, either option will work. A6.TV, A6.NET, A6.HiFi, Tv2000, A6.TV, A6.HiFi; for ASP2000, A6.NET is sufficient. 3 2 1 1 4. Legend: 1 2 3 1 2 3 1 2 3. Other appliances: A6.NET, A6.TV, A6.HiFi, A6.Home