Importance of solenoid valve power consumption

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This post was last edited by goldliyang on 2018-2-26 08:37. The importance of solenoid valve power consumption: For reasons related to safety and energy savings, chemical industry companies are increasingly paying attention to the power consumption of solenoid valves. The low-power solenoid valves commonly available on the market currently range from 1.4W to 3.7W. But most are 10W or higher, with some even reaching 15W-22W. In comparison, each low-power model consumes 10W less power than the commonly used high-power models. Next, we will analyze other differences between the two, starting with lifespan. The service life of high-power solenoid valves generally ranges from 3 to 5 years (depending on the operating conditions; in devices such as PSA air separation units, the life is shorter due to the high frequency of valve operation, with switching occurring every 4 to 6 minutes). The lifespan of low-power solenoids is significantly better than that of high-power ones. Mostly 5-10 years. Of course, it is also related to the actual operating conditions. Overall, the lifespan difference between the two types is about 3-5 years. Next, we will discuss the temperature changes during the use of solenoid valves. When the solenoid valve is in operation, its coil temperature rises due to the heat generated by the resistance of the coil. The operating ambient temperature varies greatly, depending on the region and the device. Many chemical processing units are very hot in themselves, such as catalytic cracking, reforming, dehydrogenation, etc. If the valve location is close to such devices, the ambient temperature is higher. At an ambient temperature of 30°C, the temperature rise of high-power solenoids is approximately 35°, with the coil temperature reaching around 65°. In contrast, low-power solenoids experience a very small temperature rise of only 7–10°, with their coil temperatures reaching 40–45°. High-power solenoids have a high power level, thick wire diameters inside the coils, and thus high currents. Taking ASCO EFG551H401 as an example, the coil current when powered is 0.48 A (24 V DC, ambient temperature of 25°C). To reduce the voltage drop at the solenoid valve due to the DCS output voltage, a signal cable with a cross-sectional area of at least 1.5 mm2 is required. For low-power solenoid valves, taking 1.8W as an example, with a current of 0.075A (at 24V and an ambient temperature of 25°C), a cable of 1.0mm2 or even thinner can be used. For new projects, significant savings on cable costs can be achieved here. In summary, taking a certain production workshop of a company as an example, approximately 500 pneumatic on-off valves are in use. Assuming that each valve saves 8 watts of electricity depending on whether it has high or low power consumption, the annual electricity savings amount to 8 watts × 500 valves × 8760 hours = 35,040 kilowatt-hours. At an electricity price of 0.8 yuan per kilowatt-hour, the annual savings amount to 0.8 × 35,040 = 28,032 yuan. As for the length of cables required, 100 meters is assumed per valve (excluding the return circuit); with a market price difference of around 1 yuan per meter for cables, the additional savings amount to 100 meters × 500 valves × 1 yuan = 50,000 yuan. In other words, the installation itself can result in savings of at least 50,000 yuan in terms of initial cable costs. Let’s calculate the service life again: Based on the analysis above, it can be concluded that low-power solenoid valves have a service life that is at least twice as long as that of high-power solenoid valves. The design life of the device is generally 30-50 years. This is equivalent to saving 100 solenoid valves per year on average. In summary, on a conservative estimate, each solenoid valve can save at least 700–800 yuan in total costs per year. In terms of safety, low-power solenoids have low current consumption, generate less heat, and operate at lower temperatures. Under the same conditions, their temperature rise is minimal, and the temperature coefficient of the coil has a lesser impact on the solenoid’s operation. This helps to significantly reduce the likelihood of erroneous operations by the solenoid, thereby lowering the risk of accidents. Overall improve the safety of the device. This ensures the proper operation of the automated production line, **reduces downtime caused by instrument failures, improves the efficiency of automated production over long periods, and also lowers the failure rate and maintenance costs associated with instruments. For China’s industry to achieve transformation and upgrading as well as to reduce energy consumption, it is necessary to start with the details and take action on small matters. Once again, let’s end with Dickens’ words: It is the best of times, it is the worst of times, it is the age of wisdom, it is the age of foolishness ； This is a time of faith, this is a time of doubt ； This is a season of light, this is a season of darkness ； This is the spring of hope, this is the winter of disappointment ； People have all sorts of things in front of them; at the same time, people have nothing at all ； People are going straight to heaven ； People are going straight to hell.