In principle, the valve seal pressure chamber (both pressure relief chamber) is depressurized by a weakly driven pilot valve to achieve the main valve (ie, the main valve body of the large diameter valve described above) by using the water pressure in the pipeline or For the purpose of opening the valve seal, similarly, it also closes the pressure relief chamber to achieve the purpose of closing the main valve by using the water pressure in the chamber. Fan Light,Ceiling Fan with Light,Ceiling Fans with LED Lights,LED Fan Light Yuyao Flylit Appliance Co.,Ltd , https://www.yyflylit.com At present, there are two main control methods for low-voltage electronically controlled large-diameter valves in drainage applications, one is driven by 220VAC and the other is driven by DC power. AC power is generally used to control large direct-acting valves. However, it is often not easy to obtain AC power due to the actual situation on site. Moreover, the extra power consumption will also increase the burden on the user or the management part. Therefore, in the low-pressure pipeline, it is not The best way to control. The DC power supply mode is generally powered by an adaptive power supply or battery that does not exceed 24 VDC. The water pressure in the pipeline is used to drive a motor valve such as a motor valve that controls the water passage, and a solenoid valve. Among them, battery power can minimize the impact of electromagnetic interference on the control system, and does not need to be equipped with AC power in the field, which not only reduces the control cost but also improves the reliability of the product. Therefore, the battery power supply mode is widely used.
In the battery-powered solution, disposable lithium batteries and alkaline batteries are currently used. Relatively speaking, the same volume of lithium battery can store more electricity than alkaline batteries, so it can also be used for a longer period of time. Therefore, the use of lithium batteries as the electronically controlled power source for large-diameter valves is still the mainstream. However, the lithium battery itself has a certain degree of passivation (also called memory effect), easy to fail, more south ring, not environmentally friendly, if the consistency of the lithium battery product is difficult to guarantee, the load will cause the discharge Different factors such as curves, in practical applications, lithium batteries also have problems that users and manufacturers cannot control.
On the other hand, the pilot valve currently used for weak current control (this pilot valve is different from the large-diameter valve described above), whether electromagnetic or motor type, is in principle a weakly driven pilot valve pair. The valve sealing pressure chamber (both pressure relief chamber) is pressure-relieved to achieve the purpose of opening the main valve (ie, the main valve body of the large-diameter valve described above) or the valve seal by using the water pressure in the pipeline. Similarly, it also By closing the pressure relief chamber, the purpose of closing the main valve with the water pressure in the chamber is achieved. However, in the actual use of water supply pipelines in China, problems such as the clogging of the diversion holes in the pilot valve due to prolonged water quality problems, the adsorption of iron particles or tiny gravel by the pressure relief valve stem caused the valve stem to be stuck, etc. Some designers lack practical application experience and have insufficient estimation of the site conditions. In the design stage, the design of the valve drive circuit and the control software are flawed, resulting in a high failure rate of such valves in long-term work.
In addition to the above problems, the current domestic low-pressure water supply and drainage valves are basically simple mechanical or electrical control, or even manual control, and the level of intelligence is low. Some products use RS-485, infrared, GSM, Zigbee and other communication methods for centralized or remote management. Although they have improved the level of intelligence of the products to a certain extent, they are also insufficient in application, more or less. There are problems such as low communication rate, high engineering cost, high failure rate, inflexible networking, limited network capacity, large power consumption, and complicated protocols, which not only increases the development difficulty of designers, but also restricts the improvement of user management level. Especially in the commercial water supply, it brings inconvenience to the charge management. In summary, the daily maintenance of the power supply, the valve actuator, and the intelligent control and management are the weak links of the current valve application. It is necessary to explore a technology and solution that is economical, reliable and universally applicable, and upgrade the existing electronically controlled valve. Application of the valve.
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