- Created: 14-09-21
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Description: SVG Principle The principle of the SVG static var generator is very similar to that of Active Power Filter, as demonstrated in the picture below. When the load is generating inductive or capacitive current, it makes load current lagging or leading the voltage. SVG detects the phase angle difference and generates leading or lagging current into the grid, making the phase angle of current almost the same as that of voltage on the transformer side, which means fundamental power factor is unit. Delta’s PQC series SVG is also capable of correcting load imbalance. SVG Structure Delta PQC Series SVG static var generator is also modular in design, and the Delta SVG system consists of one or several SVG modules and an optional Liquid Crystal Monitor & Control Panel (LCM). Each SVG module is an independent reactive power compensation system, and users can change the SVG rating by adding or removing SVG modules. SVG modules and LCM panel can be embedded in Delta’s standard SVG cabinet or in a customized cabinet. There are usually breakers, cable terminals and Surge Protection Device (SPD) in the SVG cabinet. Active harmonic filters are more of a system solution. How do they work? Harmonics come from the nonlinear load. Active harmonic filter, also called harmonic correction units, is parallel devices that act like a noise cancellation system and inject equal and opposite frequencies to mitigate harmonics. The filters can also provide additional current to correct the power factor. So, what’s left coming from the source flowing back to the utility is only a nice, clean current that is in phase. For example, if we run four 6-pulse variable frequency drives at the same time, we have a harmonic spectrum of 5th and 7th and 11th and 13th harmonics. The waveform will show a significant amount of harmonic current in the total harmonic distortion. When the active harmonic filter is turned on, it will inject equal and opposite harmonics to cancel what’s there. The waveform now will be clean and in phase. If we go back and look at the harmonic spectrum, the current distortion is very low. Adding active harmonic filters can be a good harmonic solution for power systems. Though more costly than other options, if you have multiple drives running all the time and multiple drives as backup, harmonic filters would be a reliable way to capture any and all of the harmonics coming from the loads. However, one important thing to know from a system design standpoint is that your drive should have either a DC choke or an AC line reactor to minimize the harmonics coming out of the drives. Active harmonic filters typically come in 50, 60, 100, 200 and 300 ampere units that you can parallel. Another benefit to using active harmonic filters is that you cannot overload them, because once they put out the maximum harmonic current and power factor correction that they can, they stop producing at that level—whether it’s 100 or 120 amperes, whatever the case may be. Using active harmonic filters on your power system provides a system-level solution for internal and external harmonic protection. What are active harmonic filters? Active harmonic filters are parallel filters (which means the current doesn’t go through the filter) that are used to reduce, or mitigate, harmonics to tolerable levels as defined by IEEE-519. Active filters use a set of transistors and capacitors to filter (or clean) the current wave by injecting inverse currents to cancel out the undesired harmonic components. Active filters are significantly more expensive than passive filters and take up more space. Size is an immense factor in system design today and should be accounted for when deciding on what type of harmonic filter is right for you. Active filters can work with multiple drives; when the active filter reaches its limit, it won’t overload. In addition, if an active filter breaks, it won’t stop the motor (since current isn’t going through the filter); it just won’t filter the current wave. Active harmonic filters can effectively cancel harmonic distortions from the network. This blog post will explain the key criteria that should be kept in mind when buying an active harmonic filter. 1.1. Inverter topology Most modern AHFs are built on 3-level NPC inverter topology which brings several benefits compared to AHFs built on the conventional 2-level topology. In 3-level topology, the switching frequency and voltage stress are distributed among the IGBTs. Reduced stress extends the lifetime of the power electronics. Higher efficiency, lower losses and lower noise levels are also achieved. These make the overall cost of ownership much lower. 1.2. Losses Depending on design and topology, AHFs can have higher or lower losses. Checking the losses is important as they will reduce the life cycle cost of the investment. Usually AHFs have about 2-3% losses (depending on rated power). AHFs built on 3-level NPC inverter topology have lower losses than 2-level ones. Depending on the user profile, reduced losses create a potential for considerable financial savings if the LCC is calculated over a period of few years. 1.3. Response time Some power quality phenomena occur extremely fast, requiring the mitigation to be even faster. If the process is affected by fast voltage fluctuations or transients, it is very important to evaluate the AHF’s overall response time. 1.4. Interharmonics Interharmonics are usually caused by synchronization issues. If the installation includes interharmonic sources, the manufacturer should be consulted as not all AHFs can deal with this. It is a common issue with cycloconverters or some types of older wind turbine generators. 1.5. Harmonic compensation capacity Harmonics can be seen in the odd and even orders. Common capacity for AHFs is 25th or 50th harmonic order. Sometimes there is a claim of being able to mitigate the 51st harmonic, which has little value as harmonic orders of 51st and above do not appear in electric power systems. An important issue is that the AHF can offer the possibility of selecting which harmonic order to compensate. For some devices, it is possible to select the whole harmonic spectrum (1st to 50th, odd and even), but for some others only few harmonic orders can be selected. Depending on the application, the capacity to compensate a certain harmonic order is a critical issue affecting the performance of the whole system. 1.6. Electromagnetic compatibility (EMC) In some countries there are strict guidelines regarding the EMC. To be sure that the AHF is not causing interference it must be fitted with a properly designed EMC filter. 1.7. Derating according to harmonic order The rating of an AHF is usually defined at nominal load (at 50/60Hz). As the AHF works further up the harmonics, its capacity compared to nominal starts to derate. For example, a derating of 50% at the 13th harmonic order means that a 100A AHF has only the capability to compensate 50A at the 13th harmonic order. Derating is a matter of how robustly the AHF is designed. This capability is more dependent on the change rate of the current than just the frequency and magnitude of the current (all different frequencies, their magnitude and phase have an effect). Because of this, a derating curve cannot show the capability of the AHF. The only way to verify the real compensating capability of a device is to check its di/dt capacity. This compensating capability is clearly better in 3-level NPC inverter topology AHFs compared to 2-level topology devices. 1.8. Physical footprint and modularity Most suppliers offer several installation alternatives: Cubicle type, wall mount or loose modules that can be locally installed inside new or existing cubicles. A modular AHF design allows customers to adapt to potential changes in future harmonic filtering and reactive power compensation needs. Modular design means that it is possible to add easily to the AHF’s capacity within the existing configuration, saving both costs and space. 1.9. Voltage AHFs are offered in a range of voltages, most common is 200V up to 690V. Some manufacturers can produce AHFs for higher voltages, up to 1000V, without step-up transformer, reducing costs and footprint. It is possible to connect AHFs to high voltage (over 1kV) systems using a suitable step-up transformer. Step-up (or step-down) transformers can reduce compensation performance due to increased impedance between the AHF and network. 1.10. HMI There are different HMI setups for AHFs. Some have a very simple front HMI while others include graphs showing the current and voltage waveforms and many further functions in different languages. A great added value is to have at least a web-based interface allowing in-depth monitoring and control functionality. 1.11. Commissioning software Commissioning and service of AHFs without proper tools can be time consuming. Some suppliers provide software for this. Minimum required functionality should be that the system performs a self-check of voltage and CT phase order, CT polarity check, self-diagnosis and self-calibration. Such features will find installation errors before they can cause problems and will shorten the commissioning time. If the AHF does not have this type of software the commissioning becomes more complex and might require external support adding to the system costs. 1.12. Smart Grid functionality Some AHFs have a built-in power quality analyser to calculate the required compensation. Some suppliers enable the user to connect all AHFs on site through a web-based architecture. An operator can then have an overview of the status of all connected AHFs and log them. This enables the possibility to log events that could have caused production disturbances, monitor individual AHFs, and remote monitoring and analysis capability. 1.13. Control of detuned capacitor banks Very often AHFs are installed at sites together with existing or new contactor or thyristor switched detuned capacitor banks. Some suppliers offer the possibility to control the steps of these banks directly from the AHF’s control system through dedicated digital outputs in the AHF. By doing this it is possible to use the comprehensive power quality monitoring and reporting features of AHFs to accurately monitor all the parameters of the installation and control the total power quality improvement needs. This brings an optimal system integration, efficient operation, cost savings on the control system, and the possibility to build hybrid var compensators (HVC). 1.14. Cancellation of harmonics in neutral (4W) Typically, active harmonic filters are installed to cancel harmonics distortions created by AC and DC drives or UPS systems. However, use of LED lighting as well as other single-phase loads in the buildings also produces tripplen harmonics which accumulate in the neutral wire and should also be mitigated. Therefore, active harmonic filter should be easily configurable to 3W or 4W applications.
Publish Date: 27-09-21
Description: The inception of the dust collector has allowed companies to effectively capture airborne particulate from an air stream. This has become more important for several reasons. First, containing particulate — toxic or not — is necessary to provide a healthy and clean work environment. Second, increasing local and global awareness of air pollution, containment and the process dust in industrial applications has emphasized the importance of dust collectors. Finally, expanding regulations have pressured companies to properly design, install, operate and maintain dust collection equipment. To ensure dust collector bags are functioning properly, you need to perform periodic inspections, as well as repair and replace damaged or malfunctioning equipment. A routine inspection and maintenance program will boost your equipment's performance and life. To maintain the health and effectiveness of your dust collector, follow our helpful list of procedures. 1. Create an inspection/maintenance program — A typical program consists of a schedule for periodic inspections that are performed on a daily, weekly, monthly, semi-annual and annual basis. Failing to periodically inspect the dust collector can hurt its performance. Subsequently, the dust collector may not meet EPA outlet emissions standards. 2. Don't exceed recommended pressure drop — Sometimes called differential pressure, it's the amount of static resistance across filters when operating a positive- or negative-pressure dust collector. Pressure drop, typically measured in inches of water column (in w.c.), is a good indicator of the amount of dust that has collected on the filter media and, if continually monitored, the condition of the filters. New filters have the lowest pressure drop because of the inherent permeability of the media. As the bags develop a dust cake, some particulate embeds itself into the filter media, increasing pressure drop accordingly. The filtering of the airstream through this accumulated dust cake provides high-efficiency collection of fine particulate. In fact, the highest efficiency a dust collector can offer is just before the cleaning is initiated. However, high differential pressures can cause filter media bleed-through or blinding. Therefore, do not to exceed the manufacturer's recommended operating pressure drop. 3. Ensure cleaning system functions properly — Equipment use a variety of cleaning systems to dislodge accumulated dust cake from the filter media. Systems include reverse air, shaker or pulse clean. Regardless of the style of cleaning, it is imperative that this system function properly at all times. Without an effective cleaning system, dust will continue to build on the bags. The result will be an increased pressure drop and reduced volume of ventilation air at the pick-up points. Further, airstream velocities within the ductwork will decrease and cause dropout of dust in the ducts. This may choke the entire system and render it ineffective. 4. Watch for visible emissions — This includes any particulate that can be seen discharging from the exhaust stack. These emissions indicate a breach in a seal or a broken (torn) filter. In either case, you must find and correct the leak immediately. Not only will the emission cause a health concern and damage the property outside the plant, but it may also bring about monetary fines imposed by local, state and federal environmental agencies. Additionally, fans located downstream of the collector can be damaged from abrasion or become imbalanced if you don't correct this condition quickly. Continually monitor exhaust from the dust collector. Besides visual inspections, consider incorporating a broken bag detector into the clean air ductwork. If a bag begins to fail, or there's a leak in the bag seal, you'll detect the particles that bypass the media. Typically, these detectors use triboelectric technology. These devices can be wired to an alarm horn, siren or PLC. 5. Select the right exhaust fan — Dust collection systems require an exhaust fan to accelerate ventilation air from the point of pick-up, through the ductwork and dust collector filter media and out the exhaust stack. Fans are selected to accommodate volume (SCFM) and pressure drop throughout the system. Calculate the pressure drop by evaluating the static resistance of the dust collector, ductwork and pick-up points/hoods. 6. Inspect the filter media — This is the most important item in a dust collector because it accumulates and supports a dust cake. This dust cake is what provides high filtering efficiencies during operation. Inspect the clean-air side of the dust collector for leaks and the bags for tears. If pressure-drop within a dust collector becomes extremely high relative to historical data, it may be caused by excessive dust cake or blinding of the filter bags. Depending on the application, differential pressure may take a number of hours or even days to develop. It is essential that you keep filtering velocities low for new filter media. Reducing the volume decreases the airstream's velocity, thus protecting the bags from high-velocity impingement of dust. If you expose bags to the fan's full volume, fine particles may embed themselves into the bags' inner fibers and begin blinding. This can also reduce the life of the bags by damaging the fibers of the media. So make sure to season a collector's filter bags. This is not an all-inclusive list. Each piece of equipment and application is different, and each has its own unique components and features. But these simple procedures can help you monitor and maintain your dust collector's heath, as well as prevent shutdowns due to inefficiencies, prolong filter life and prevent costly EPA fines. Dust Filter Bag The welding of the filter bag cage is not standardized. The unevenness of the welding frame of the filter bag cage or friction with the cabinet will cause the dust filter bag to be worn out during shaking. Generally, the uneven surface of the filter bag cage refers to burrs or edges at the welding place; The dust bag installation is not standard. The dust filter bags are too loose when suspended, which may cause the dust filter bag to collide or friction with other components, resulting in damage to itself; The disassembly and assembly of the dust filter bag is not standard. When the dust filter bag is disassembled or installed, it is likely to collide with metal edges and wear the cloth bag. This kind of injury is not easy to detect, but ash will appear during work; The cleaning cycle is unreasonable. The dust removal cycle is too short and the dust removal method is wrong, which will increase the burden on the dust filter bag and cause the dust filter bag to be easily damaged; Dust-containing gas properties. The temperature of the dusty gas is too high, the concentration is too high, and the wind speed is too high, etc., it will increase the burden of the dust filter bag and easily cause premature damage to the dust filter bag. In addition, if the dust filter bag used fails to match this working condition, it is easy to burn. On the contrary, if the temperature is too low and the wind speed is low, it is easy to cause condensation and dust removal of the dust filter bag. The high dust filter bag needs to be replaced. Five Things You Should Know about Dust Collection Filter Media #1: Most industrial dust collection manufacturers design filters or collectors. Few design both. The customer wins when a manufacturer understands the behavior of both the filter media and the dust collector and designs both. When a supplier can optimize the interaction between the filter media’s performance and the collector’s performance as a single consolidated system, the customer benefits by a more stable and dependable operation and lower operating costs. #2: Effective filter media designs may require thousands of computer simulations before initial lab samples are produced or final media grades are released to production. Filter media development is very involved and includes the testing of raw materials and properties of filter media blends. Raw material testing and media development labs often evaluate media components using: high-performance liquid chromatography (HPLC), FTIR (Fourier Transform Infrared) Spectroscopy, TD-GC-MS (Thermogravimetric Analyzer - Gas Chromatography - Mass Spectrometry), and SEM (Scanning Electron Microscopy). These tools help ensure the optimal design and materials are being used to appropriately match the application conditions. Development of Donaldson media grades includes computer modeling to predict tensile strength, stiffness, permeability, and a variety of other filtration and efficiency levels. This modeling helps ensure a thorough understanding of the potential physical properties of a media recipe before a test recipe is even produced in the lab. When a recipe shows promise, samples are produced in the lab so physical testing can confirm the predicted properties. Donaldson considers filter media development one of its core competencies. Even so, with all our background and experience, new media recipes still go through thousands of computer and lab iterations to achieve the optimized characteristics before we begin production of a new media grade. #3: There’s more to manufacturing filter media than meets the eye. The general process of developing any filter media should begin by identifying the application requirements. Then specifications are determined for not only the finished media grade, but for the final filtration product in which the dust filter media grade will be incorporated (i.e. cartridge, panel, or filter pack). Factors to be considered in media recipe formulation include: a cost level which makes sense for the market; minimum efficiency levels needed to achieve acceptable emissions; the type and amount of material being filtered from the fluid stream by the media filter; and the physical environment to which the media will be exposed. Other factors include: pressure, vibration, temperature, humidity, and chemical composition of contaminants. Pressure drop, or the resistance necessary to cause fluid flow through the media, is considered critical to media design because this impacts the energy it takes to move fluid through the media and, therefore, the operating cost of the filter developed. All of these variables are considered important, and they must be balanced against one another to formulate an optimized media grade for an application. For example, a formulation may use expensive materials and provide high efficiency, yet the very dense filter media might be expensive to operate in the collector because of the high pressure drop of the filter and its replacement costs. A dense filter media design might also compromise the performance of a cleaning system and could result in shorter overall filter life and increased maintenance material and labor costs. On the other end of the spectrum, a filter media comprised of low cost materials with low pressure resistance may offer initial benefits. However, if the media does not handle the physical challenges of the operation or becomes quickly plugged, the operational disruption and maintenance downtime and expense make it a poor choice. Optimizing the various performance measures is essential to overall collector performance. #4: Some manufacturers offer 300+ grades of filter media from which to choose. Some manufacturers are so serious about providing exactly what the customer needs they offer hundreds of choices to the market, each tailored to meet specific challenges and requirements. If an appropriate media does not exist for an application, new media development may be undertaken. #5: Evaluating dust collection manufacturers pays off. When evaluating dust collection manufacturers, look for one that offers media grades optimized for your application and for the collector in which they will operate. This will help optimize your filter efficiency performance, extend your filter life, and lower your cost of ownership. Choose a company with a strong history of providing expertise and technical support. If you’re employed by a global company, consider a global dust collection manufacturer that can provide excellent customer support around the world – including stock inventory of common filters and parts so they are ready to ship when you need them. A company like this will provide you exactly what you need.
Publish Date: 27-09-21
Description: Humidifier adds moisture to the air, which can benefit people with respiratory symptoms or dry skin. There are several ways to use humidifiers in the home or office, but there are also some risks. In this article, learn about the benefits of humidifiers, how to use them correctly, and precautions to take. Dryness and humidity By adding moisture to the air, humidifiers may be beneficial for several medical conditions. Dry air can cause moisture to evaporate from the skin and respiratory symptoms to worsen over time. Adding moisture to the air with a humidifier can counteract these problems. Humidifiers can help people who experience: dry skin irritated eyes dryness in the throat or airways allergies frequent coughs bloody noses sinus headaches cracked lips Five humidifier uses and their benefits Some people experience respiratory symptoms in the summer months, when the weather is hot, and the air contains more allergens. Air conditioners and fans can circulate dry air through the room, and air conditioners remove any moisture from the air. A humidifier may be beneficial during this season. However, people are more likely to benefit from a humidifier in the cold months, when cold air dries out the lungs, nose, and lips. Also, some types of central heating can dry out the air indoors. Benefits of a humidifier may include: 1. Preventing influenza Authors of one studyTrusted Source noted that humidifiers might reduce the risk of catching the flu. After adding the influenza virus to the air with a simulated cough, researchers found that humidity levels above 40 percent rapidly deactivated virus particles, making them much less likely to be infectious. 2. Making a cough more productive Dry air can cause a person to have a dry, unproductive cough. Adding humidity to the air can get more moisture into the airways, which can make a cough more productive. A productive cough releases trapped or sticky phlegm. 3. Reducing snoring Increasing the amount of moisture in the air can also reduce snoring. If the air is dry, a person’s airways are less likely to be sufficiently lubricated, which can make snoring worse. Adding humidity to the air by running a humidifier at night may help to relieve some symptoms. 4. Keeping the skin and hair moist Some people notice that their skin, lips, and hair become dry and fragile in the winter. Many types of heating units pump hot, dry air through the house or office, which can make the skin dry, itchy, or flaky. Cold air outside can also dry out the skin. Using a humidifier to add moisture to the indoor air may help to reduce the occurrence of dry, cracked skin. 5. Benefits for the home Moisture from a humidifier can be helpful around the home. Any moisture-loving houseplants may become more vibrant, and wood floors or furniture may last longer. Humidity can also help to prevent wallpaper from cracking and static electricity from building up. Humid air can also feel warmer than dry air, which could help a person to save money on utility bills in winter months. Types of humidifiers While most humidifiers have the same basic function, to add moisture to the air, many types are available: Steam vaporizers: These use electricity to create steam, which cools before it leaves the unit. However, there is a risk of burning the skin, and people should avoid using steam vaporizers around children. Ultrasonic humidifier: Instead of electricity, these units use vibrations to vaporize water. Evaporators: These produce humidity by blowing air past evaporating water. Impeller humidifiers: These are generally child-friendly and use rotating disks, rather than heat, to vaporize water. Central humidifiers: A person connects one of these units to the central air conditioning in the home or office to add moisture to the entire space. Sizes can vary. Console humidifiers are large enough to add moisture to an entire house or office, while personal humidifiers are portable and easy to carry. What is an Industrial Humidifier? An industrial humidifier is a system that is capable of providing adequate humidity levels in a manufacturing environment. High-speed production processes add to the heat load in a building, bringing down the humidity. This can lead to a dangerous buildup of static electricity in a plant where dust and other flammable materials may be in the air. Processes such as woodworking, printing, and electronic and microchip fabrication, — which involve gluing, coating, and bonding — benefit from humidity control. Energy efficiency is also a consideration with an industrial humidifier. Related products include industrial steam humidifiers, as well as electric-powered and gas-fired models. Steam heat exchangers use a heat source for producing steam from tap water or pure water reserves. These are also designed to comply with indoor air quality requirements to ensure proper humidity levels along with clean air for workers. Industrial humidifiers are also designed as fog systems that integrate with building automation systems. In this configuration, an industrial humidifier system can be integrated above the factory floor, with the moisture released via fog nozzles. This is a viable alternative to humidifying air traveling through ducts, because excessive heat loads can be managed at the source. An industrial humidifier also can be a contamination control system. It can be capable of utilizing adiabatic humidification to control humidity and airborne particles, and reduce the buildup of electrostatic discharge that, when combined with particulates, can be a health hazard and a cause for major industrial accidents. Along with proper treatment of supply water, an industrial humidification system ensures a safe environment in which to work. An industrial humidifier can be found in many manufacturing facilities. Plants that make electronic assemblies require humidification, because the air in buildings producing circuit boards and computer equipment must be free of particles. Semiconductor manufacturing is another major application, because integrated circuit printing requires tightly controlled temperatures, along with a relative humidity (RH) of around 35 percent to 45 percent with acceptable tolerances within a range of 1/2 percent to 5 percent RH. What Does a Dehumidifier Do? A dehumidifier is an appliance that takes moisture out of the air in your home. If you or your family members have asthma or allergies, a dehumidifier might help relieve symptoms and make breathing easier. This article will help you decide whether a dehumidifier is a worthwhile investment for your living space. Dehumidifier uses and health benefits You may remember the water cycle from elementary school science: evaporation, condensation, and precipitation. What you might not realize is that the water cycle is always taking place in the air you’re breathing, even when you’re spending time inside. “Humidity” is a measure of water vapor in the air. Dehumidifiers remove or minimize this water vapor. How a dehumidifier works A dehumidifier works by drawing warm air currents into its coils via a fan. The warm air contracts as it’s fed through the refrigerated coils of the machine, and condensation is left inside the dehumidifier. As this condensation collects, one droplet of water at a time, it falls into a storage tank attached to the dehumidifier. Cooler, drier air is then released back into your home through the other side of the machine. Your dehumidifier should be able to bring the moisture in the air down to a relative humidity of 30 to 50 percent. Many dehumidifiers come with a meter that measures the relative humidity where it’s placed in your home, and you can set the humidity to the percentage you desire. Application of Dehumidifiers for Various Industries Food Industry: Excess humidity causes condensation and a broad range of hygiene problems in the product. Be it powdered food, spices, processed meat, snack foods confectionery products or breweries, consistent and controlled moisture conditions are necessary. Using dry air from a Desiccant dehumidifier can help in controlling the moisture content, which leads to perfect coating and longer shelf life of the food products. Lithium Batteries: The primary requirement for manufacturing of lithium batteries is a dry room with very low humidity. Lithium is extremely sensitive to moisture; thus, high moisture content leads to a reduction in performance and life of the product. Industrial dehumidifier ensures that the processing areas have the required amount of moisture in the air which is less than 14gms of moisture per kg of dry air. Pharmaceutical Industry: During the processing stage, most of the medicines are in powdered form and are highly hygroscopic. Excess of moisture absorption leads to organic corrosion, biochemical reactions and micro-organism growth on the product. Dehumidifiers help in keeping the required humidity parameters for processing, drying, storing and transportation of medicines. Cold Stores: To prevent flowers, vegetables, fruits, milk and processed foods from deterioration they are cooled and stored in cold store under low moisture conditions. Since the cold stores experience the frequent movement of products, warm air with moisture from outside could enter the store. This results in ice and frost formation on the walls, floors and ceilings on the cold stores. Air curtain using Dehumidified air at the cold store doors helps in controlling the ingress of moisture laden entering the cold rooms. Defense Industry: Military equipment is highly prone to humidity damage when they are stored for long periods. Uncontrolled humidity causes corrosion and malfunctioning of equipment, fungal growth on maps, drawings and bacterial infection on rations. Storage rooms of standard equipment such as trucks, tanks, guns and ammunition require specific humidity levels and controlled temperature. Dehumidifiers help in preventing corrosion on the equipment by keeping humidity levels less than 35%. Electronic and Semiconductors: Components used in assembling or processing of semiconductors are hygroscopic and highly sensitive to excess humidity. Excess moisture results in corrosion of PCB, transistor failures, and condensation on integrated circuits. The RH in semiconductor manufacturing area must be 30% at 20oc. Industrial dehumidifiers also help in protecting the vacuum and EPI equipment. Turbine Industry: Moisture can corrode turbines, boilers, condensers and many other machines when they are kept for maintenance during the layup process. High humidity causes corrosion and rusting on the equipment leading to their malfunctioning. As the repair and downtime costs of these equipment are very high, moisture control becomes essential. Industrial dehumidifiers help in keeping moisture levels low during the storage of the product; thus, preventing corrosion. Leather industry: The Leather is a hygroscopic material; excess moisture leads to the growth of mold and mildew on leather. Without proper humidity control, leather loses its shine, produces the foul smell, loses its strength and starts decomposing. Relative humidity above 40% leads to micro-organism growth that results in decomposition of leather. Dehumidifiers help in providing controlled moisture conditions during the processing of leather products. Ultrasonic Mist Maker I needed a simple mist maker/humidifier for a project that I was working on. I found lots of ideas on the internet, but they all lacked in one area or another, so I decided to design one. The following lays out my easy-to-build ultrasonic mist maker. It works fine and is, by far, the easiest ultrasonic mist maker/humidifier that I’ve ever had to get going. The misty head In an ultrasonic mist maker/humidifier (also called an ultrasonic atomizer), a piezo atomizer disc/transducer (ceramic humidifier) works by transposing high-frequency sound waves into mechanical energy that is transferred into a liquid, creating standing waves. As the liquid exits the atomizing surface of the disc, it’s broken into a fine mist of uniform micron-sized droplets, so the key component required for this little project is a particular (20-mm, 113-kHz) ultrasonic atomizer disc/transducer (see below). When buying the transducer, make sure that is has a 113-kHz (±3 kHz) resonance frequency — another popular transducer has a 1.65-MHz (±0.05 MHz) resonance frequency, which is not compatible with this project! Circuit diagram of the transducer driver Below is the circuit diagram of the final part of the project — the transducer driver. As shown in the circuit diagram, it’s a tricky oscillator design based on the ubiquitous tiny time chip NE555P (IC1) to generate proper drive pulse train for the atomizer transducer. In the circuit, the 5K multiturn trimpot (RP1) can be used to set the oscillator frequency to 113 kHz (±5 kHz) (TP1). Even though the ultrasonic mist maker device is configured to run on a single 5-Vdc to 12-Vdc input, this transducer driver needs a 20-Vdc to 26-Vdc (V_DRIVE) power supply channel in addition to a 5-V regulated DC supply rail. So a dedicated power supply circuitry will be introduced later to fulfill that crucial requirement.
Publish Date: 27-09-21
Description: According to the U.S. Environmental Protection Agency (EPA), traditional gasoline lawn mower is a public nuisance to say the least. Using one of them for an hour generates as many volatile organic compounds—dangerous airborne pollutants known to exacerbate human respiratory and cardiovascular problems—as driving a typical car for 350 miles. The EPA estimates that, with some 54 million Americans mowing their lawns on a weekly basis, gas lawn mower emissions account for as much as five percent of the nation’s total air pollution. Beyond that, homeowners spill some 17 million gallons of gasoline every year just refueling their lawn mowers. So what’s a green-minded property owner to do about keeping the grass down? Go electric, of course! Electric mowers, which either plug into a wall outlet via a long cord or run on batteries charged up from the grid, create no exhaust emissions and run much cleaner than their gas-powered counterparts. They also need less maintenance, with no spark plugs or belts to worry about, and are easier to use, as they tend to be smaller and come with push-button starters. The icing on the cake might be the fact that electric mowers are cheaper to run, using about as much electricity as an ordinary toaster. Most electric mower owners spend about $5 a year on electricity to keep their grass trimmed just right. The non-profit Electric Power Research Institute reports that replacing half of the 1.3 million or so gas mowers in the U.S. with electric models would save the equivalent amount of emissions of taking two million cars off the road. But going electric has some minor trade-offs. Electric mowers tend to cost up to $150 more than their gas-powered counterparts, and the plug-in varieties can only go 100 feet from the closest outlet without an extension cord. And the cordless models last only 30-60 minutes on a charge, depending on battery size and type, though that’s plenty sufficient for the average lawn (just remember to re-charge it in time for the next mow). And, of course, just because electric mowers don’t consume fossil fuels or spew emissions directly doesn’t mean they are totally green-friendly. Most people derive their household electricity from coal-fired power plants, the dirtiest of all energy sources. Of course, running an electric mower on electricity generated from clean and renewable sources (solar, wind or hydro power) would be the greenest of all possibilities, and those days may be upon us soon. In the market for a new lawn mower, but not sure which type is best? Let us help you navigate the debate on electric vs. gas lawn mowers. With more lawn mower models on the market than ever before, and so many sizes, styles and features to consider, making the best choice isn’t as simple as it once was. And now, electric mowers are making a big splash in the lawn care industry. Not long ago, mower motors required too much juice for a cord or batteries to be practical. Not anymore. Modern refinements and innovations allowed corded and battery-powered electric mowers, such as twin-battery mower, to burst onto the scene with gusto. Gas-burning mowers ignite a mixture of air and fuel, compressing it in a cylinder, then igniting it with a spark to create a miniature explosion which is harnessed to power the machine. Electric mower motors, however, feature magnets interacting with electromagnets, energizing metal coils to move rotors and create power. Electric mowers can be powered by batteries or a 120-volt receptacle via extension cord. Motor Power Lawn mower manufacturers can be disingenuous about the real world power levels of their products. It’s not uncommon for electric mowers, for example, to have their “max torque” specs touted as evidence they match gas-burning models in power output. This is deceptive. Max torque gives an inflated perspective of a mower’s true power because it measures engine torque under little or no load. The fact is, horsepower is the only reasonable unit of measure for lawn mowers, which I suspect is why electric mower manufacturers don’t share this figure. The real-world horsepower of most electric mowers is half, or less than half, the horsepower of a similarly sized gas-powered machine. Run Time It’s hard to measure exactly how much run time you’ll get from a tank of gas in your average fuel-burning mower, because much depends on the speed you run it and the density of the grass you’re cutting. It’s a safe bet, though, that a tank of gas will last longer than a fully charged battery on any equivalent electric model. Most electric mower manufacturers give a maximum run time estimate, which for push and self-propelled mowers is almost always an hour or less. Riding electric mowers might run two hours, tops, on a single charge. Plug-in mowers don’t require batteries and will keep running continuously unless there’s a power outage. In that case, a generator with sufficient voltage capacity can keep you going. The Environment and Noise While power and run time certainly favor gas-powered mowers, noise and environmental considerations support electric. Battery-powered mowers have zero carbon emissions, so running one won’t contribute to climate change. Noise is also a factor worth considering. Many municipalities regulate the acceptable amount of yard noise. Big, beefy gas-powered mowers can easily exceed these guidelines, but battery-powered mowers almost certainly won’t. Note: Some users find vibration is more severe and bothersome with gas burning mowers than electric. Operating and Maintenance Costs Although it’s tempting to believe battery-powered mowers will always cost less than gas-burning mowers long-term, this isn’t necessarily the case. Although you’ll almost certainly spend less on electricity charging your batteries or running your corded mower then on gas and oil for your fuel-burning machine, there’s more to the equation. Lithium ion batteries don’t last forever and eventually need replacement. They’re not cheap, either. If your electric mower comes with a generous warranty, you might be lucky enough to get a replacement battery (or batteries, if your mower takes two) for free when yours bites the dust. Otherwise, you could be looking at a $200 to $400 expense. Ease of Use Robotic lawn mower is usually simpler to use and maintain than their gas-powered counterparts. They don’t need gas, oil changes or new air filters, and you don’t have to make sure the carburetor and spark plugs are clean and functional. Electric Lawn Mower Pros Much quieter; Lower maintenance (no fueling, oil changes, belt replacements, air filter changes, etc.); Zero carbon emissions; Lighter weight (matters for push mowers you need to lift and store). Electric Lawn Mower Cons Battery power only lasts a couple hours (and often less) before requiring charging; Corded models can only be used near a power source, unless you have an extremely long extension cord; Extension cords are troublesome to lay out and roll up again for storage; Often have much less power than most equivalent gas-burning models; Replacement batteries are often expensive. Gas Lawn Mower Pros Generally much more powerful than electric mowers; Don’t require cords or batteries; Often built tougher; Replacement parts are often less expensive than those for electric mowers. Gas Lawn Mower Cons Considerably louder than electric mowers; More costly to run (unless you need to replace a battery outside the warranty period); Require more maintenance (oil changes, fuel preservative added during off-season, etc.); Generate carbon emissions. How To Choose the Right Mower Battery-powered mowers work best for people with small lots who want to minimize maintenance, noise and carbon emissions. But if noise and exhaust don’t bother you, and you just want to mow and be done with it as quickly as possible, you’re probably better off using gasoline engine. Whether you go with gas or electric, it’s important to choose the right model for your needs. If you’ve got an acre or less to mow, a self-propelled walk-behind mower is probably your best bet. If you’ve got a larger lawn or simply don’t like walking and mowing at the same time, a riding mower will make your life much easier. More detailed considerations like engine power, blade speed, deck width, regular range and other features come down to personal preference and available budget. Cordless Lawn Mowers have taken over the lawn and garden section in many retail stores. Six years ago, Tool Box Buzz ran a Best Cordless Lawn Mower Head-to-Head test of five cordless mowers, so we were really interested in how the field of manufacturers has increased and how the offerings have changed after six years. Our 2020 cordless lawn mower head-to-head will answer the question of whether cordless mowers’ performance “cut it” when compared to a gas-powered mower. Why Cordless Lawn Mowers? Even when operated correctly, gas-powered mowers require lots of service including oil changes, fuel filters, spark plugs, and air filters. Oftentimes people wait to do service until the mower won’t start! Anyone who has had to get a small engine repaired knows the hassle and time-sink that can be. Cordless mowers eliminate all of the above-mentioned maintenance, last-minute fuel purchases and they’re quieter to operate and do not emit fumes. Landscaping on wheels. Thats what lawn and garden tractors provide. If you're serious about having a professional looking lawn, then you need to move beyond a simple mower. At this level, mowing becomes just one task out of many that you need to perform. Enter the lawn tractor, a heavy-duty machine that lets you handle whatever curveballs your lawn throws your way, from dethatching, to aerating, to snow plowing. Keep reading to learn about the different types of lawn tractors and how to pick one. How to Choose a Lawn Tractor When deciding what kind of lawn tractor is best for your yard, you should consider what you'll be using it for. If you just need it for some light mowing on a small yard, then a standard lawn tractor will work fine. However, if you want to use heavier attachments for aerating, dethatching, or even tilling, then you'll need a heavy-duty garden tractor. Two important factors to consider when shopping for the perfect lawn tractor are the grade and the deck size of the tractor. 1. Select a Grade Lawn tractors can be grouped into the following grades: Standard Lawn Tractors Standard lawn tractors provide great power and versatility. They have twin cylinder engines for low-end torque and are a must if you intend to mow large areas or use any attachments on a regular basis. Some tasks that lawn tractors can perform with the proper attachements include aerating, dethatching, spraying, spreading, and even snow plowing during winter. Lawn tractors are designed with hydrostatic transmissions, which offer simple speed adjustments while driving. There are two hydrostatic transmission options: lever or pedal-operated. The pedal-operated option provides the most comfort and flexibility in speed. Garden Tractors Garden tractor is lawn tractors on steroids, capable of everything lawn tractors can do plus tilling, furrowing, towing heavier cart loads, and more. Their rugged decks, anti-scalp wheels, and powerful engines enable them to slash through tough brush. They also include forged or cast iron axles, which are stronger and a good indicator of overall quality level. Finally, their larger back tires provide extra ground clearance and enhanced stability on slopes and inclines. However, if you're dealing with slopes greater than 15%, you should consider a tractor with a traction control system or locking rear differential.
Publish Date: 24-09-21
Description: Plasma cutting has come a long way since it was first developed in the late 1950s by engineers at Union Carbide Corp. Today it is one of the most widely used metal plate cutting processes for a large variety of industries. Early plasma cutting systems were used primarily for cutting stainless steel and aluminum plate from 0.5 to more than 6 in. thick. These systems, primitive by today’s design standards, were the most practical method for cutting heavy nonferrous plate. Most were mounted on XY cutting pantograph-style machines that used either photo-cell tracers to duplicate large black line engineering drawings of the parts to be cut, or a magnetic tracer to follow the path of a steel template. Engineers continuously worked on the process throughout the 1960s with the goal of improving cut quality and the life of the consumable nozzles and electrodes in the cutting torch. Plasma began gaining momentum during this period as the process improved and as users became aware of its ability to cut complex shapes in nonferrous materials at very high speeds. In 1968 radial water injection was introduced. This patented nozzle technology used pure water injected radially around the plasma jet to constrict the arc, increasing its energy density while improving nozzle cooling and thus allowing faster cut speeds, higher-quality cuts, and the ability to cut carbon steels at speeds four to six times faster than an oxyfuel cutting process. At about that same time, XY coordinate drive cutting machine technology was being improved. Microprocessor control technology started to become the brains of the XY motion control machines, allowing for better accuracy, higher cutting speeds (necessary for the new-technology plasma systems), and higher levels of automation and productivity on the shop floor. Through the 1970s plasma cutting technology replaced many oxyfuel-based steel cutting applications from 0.25 to 1 in. thick, while still maintaining its stronghold on the stainless and aluminum markets. While plasma could cut steel thicker than 1 in., the oxyfuel process still was a lower-cost alternative for heavier steel plate. Timeline of Major Engineering Breakthroughs With the baseline of plasma’s early history established, let’s take a look at some of the major engineering breakthroughs with this technology: 1957 The plasma cutting process was developed and patented by Union Carbide as an extension of the gas tungsten arc welding (GTAW) process. 1962-1967 Several new developments were completed in consumable design, and the dual flow torch was designed to help improve consumable life and cut quality on nonferrous materials. 1968 The water injection process was commercialized. This process allowed for cutting with clean, square-cut edges and faster speeds, as well as cutting of carbon steels with acceptable cut quality. 1970-1979 The water table and water muffler, designed to provide fume and smoke control, debuted. Automated arc voltage-based height controls for more consistent cut quality and longer consumable parts life emerged. 1980-1984 Oxygen-based plasma cutting systems that helped improve edge squareness and edge metallurgy (softer, weldable edge) and allowed for cutting carbon steels at lower power levels and higher cut speeds (see Figure 2) were introduced. 1984-1990 Many developments in the air plasma cutting process allowed for better portability and lower power levels for hand cutting and mechanized thin-sheet cutting. 1990 Better power supply designs using pulse width-modulated, current-controlled outputs were developed. Some systems started to use lighter-weight, smaller inverter technology power supplies suitable for portable, hand-held plasma systems. 1992 Long-life oxygen process technology was introduced. This was essentially a microprocessor-controlled method of controlling plasma gas ramping pressures as well as power supply output amperage. It helped increase typical oxygen plasma consumable parts life by four to six times; improved parts consistency; and helped lower the cost of plasma cutting. 1993 High-definition plasma, a technique that required the previous long-life oxygen technology to implement, was developed. This process allowed for a new nozzle design that increased the energy density of an oxygen plasma arc by as much as four times, allowing for squarer, cleaner cuts in all material thicknesses. 1996 Automated gas flow control systems emerged. They interfaced digitally with the machines’ CNCs. These gas flow controls eliminated some of the potential for machine operator-related errors in setting parameters for the cutting process. 1996-2006 Many developments occurred relating to improving cut quality and productivity and automating the many process cut parameters. These included integrated plasma, a system that closely coupled the CNC, the plasma power supply, the gas flow control, the CAM software, and the height control system to automate the process. With this expertise built into the system, the machine operator’s job became much simpler, and the process relied less on operator expertise. Recent Technology Developments In the last seven years, developments in plasma cutting technology have come at a fast pace. The latest revision on high-definition machines is their full integration with the CNC machines they are coupled with. New CNCs have touchscreen accessibility, minimizing the number of buttons involved in operating a plasma cutting machine and making operation as simple as almost any Windows?-based software. Operator training has been simplified on even the largest, most complex CNC plasma cutting machines. The operator’s job also has been made easier with improvements in auto-calibrating height control functionality. The operator does not need to make adjustments as the consumable parts in the torch wear out. Hole cutting has been improved with a large database of information in the CAM software that automatically recognizes CAD features and implements the best possible cut path and plasma cutting parameters, including on-the-fly shield gas changes that nearly eliminate the normal taper found in plasma-cut holes on steel (see Figure 3). This process is transparent to the machine operator and system programmer, eliminating the need for them to be experts. Improvements in cut-to-cut cycle times have been incorporated into CAM software. The software automatically recognizes areas of a full cutting nest (multiple parts) and modifies the traverse time, torch retract time, and gas preflow time to decrease production times and improve product throughput. Nesting software now applies the lead-in points in the most effective way to avoid traversing over areas prone to collisions with previously cut parts. Improved plate beveling software has simplified the integration and operation of a bevel head with XY CNC cutting machines. This advancement, again associated with the system’s CAM software, saves much of the programmer/operator trial-and-error testing that has always been necessary to hold the best tolerances on plate edge beveling applications, such as weld prep. Very new vented nozzle and gas mixing technology has helped improve stainless steel edge quality. Edges are squarer, shiny, and weldable. Air plasma cutting systems from the major manufacturers also improved dramatically in terms of cut quality, consumable life, and duty cycles. These systems, primarily designed for portable and in-shop hand-held cutting applications, now are available with quick-change mechanized torches and interface easily to a variety of lower-cost CNC machines. Systems are available from a 30-amp, toaster-sized unit that operates on 120-V household current to sever materials up to 0.5 in. thick, to a 125-amp, 100 percent duty cycle industrial unit that can sever 2.25-in. materials. Both portable systems can be used with a hand torch or can be mechanized for a variety of automated cutting applications. Industrial mechanized systems typically are 100 percent duty cycle, available with machine torches, and designed to use a variety of compressed gases to fine-tune the cut quality for different materials. These systems are available in various sizes and capacities from 130 to 800 amps. Many other advances have been made to improve reliability, performance, consumable life, cut quality, and ease of use since the first plasma system was created. The process shares the cutting market with laser cutting, abrasive waterjet, and oxyfuel cutting, all of which deliver accuracy, productivity, and long-term cost-effectiveness when used for the appropriate applications. What can be considered light duty? A light duty plasma cutting machine can become a need for any workshop, artist, contractor, etc. that so far have been using oxy-fuel and is ready to make the leap to a better solution. Actually, after experiencing a handheld plasma machine, almost nobody wants to return to oxy-fuel. That is because even a light-duty plasma cutting system can make a big difference in efficiency and productivity. So, in this post, we are going to consider what a light-duty plasma cutting system is and which one you should get. But before getting into this amazing topic, let’s consider what plasma cutting is. Most people classify plasma cutting systems in light, medium and heavy-duty. A handheld plasma cutting machine used in a small cutting table can be considered light-duty. In general terms, a medium-size cutting table powered by some plasma cutting machine would be a medium-duty system. A mechanized cutting system, which could occupy the heavy-duty slot, can be built in a stronger structure and composed by more than one cutting machine. But that classification is not a general rule for plasma cutting manufacturers. For the sake of this post, as quoted before, we are considering a handheld or portable plasma cutting machine as a light-duty one. Now, before buying a light-duty plasma system, you may need to know when to use a portable and when to use an automated system. So, let’s consider some of it. What Are The Advantages Of Fiber Laser Cutting Machine Fiber laser is well received in the market now, because of its outstanding advantages of good beam quality and high conversion efficiency, it is widely loved in some finishing fields. At present, the proportion of fiber laser in the industrial field is close to 50%, which is also a kind of active choice for products in many industrial applications. Compared with traditional gas and solid-state lasers, fiber lasers have great advantages as frequency conversion light sources. In this article, we are going to talk about what is fiber laser cutting machine, what are the features, advantages & benefits of fiber laser cutting machine and applications & uses of fiber laser cutting machine. What Is A Fiber Laser Cutting Machine? Fiber laser cutting machine is a new type of machine in the world, which is used to output high energy density laser beam. The laser beam is concentrated on the surface of the workpiece, so that the area of ultra-fine focus on the workpiece is instantly melted and evaporated, and the spot is moved through the CNC mechanical system. Automatic cutting by illuminating the position. Compared with large volume gas laser and solid-state laser, it has obvious advantages and has gradually become an important choice in high-precision laser processing, lidar system, space technology, laser medicine and other fields. The optical plate fiber laser cutting machine can be used for both plane cutting and oblique cutting, with neat and smooth edges. It is suitable for high precision cutting of metal plate. At the same time, the manipulator can replace the original five axis laser for 3D cutting. Compared with ordinary CO2 laser cutting machine, it saves more space and gas consumption, and has high photoelectric conversion rate. It is a new energy-saving and environmental protection product, and also one of the world’s leading technology products.
Publish Date: 24-09-21
Description: This paper proposes a new configuration of a single-phase hybrid inverter with an integrated battery energy storage, which is suitable for residential households to maximize local consumption of solar energy and thus reduce dependency on grid support. The hybrid inverter is called Direct Storage Hybrid (DSH) Inverter. A transformer-less topology such as HERIC, operating at low frequency to generate a three-level rectangular output voltage, is adopted to connect a photovoltaic (PV) panel to the load and/or the grid. A series active filter is employed to compensate the high harmonic components from the rectangular voltage and provide a sinusoidal voltage. A bidirectional dc/dc converter connects the battery to the PV panel to control the battery state of charge (SoC) and optimize the PV panel operation during both off-grid and grid-connected modes. The DSH inverter can let the battery bypass the dc/dc converter and connect directly to the inverter stage, leading to a significant improvement in throughput efficiency in battery utilization. This paper discusses the operation and loss analysis of the DSH inverter in off-grid mode. This paper is designed in such a way that it overcomes this limitation by the use of solar energy. NA hybrid inverter lv with Solar Battery Charging System consists of an inverter powered by a 12V Battery. This inverter generates up to 230V AC with the help of driver circuitry and a heavy load transformer. This battery gets charged from two sources, first being the mains power supply itself and second from the solar power. If the mains power supply is available, then the relay switches to main power supply for supplying the load. This power supply also charges the battery for using it as back up the next time when there is a power outage. The use of solar panel to charge the battery gives an additional advantage of surplus power in case the power outage of mains is prolonging. Thus this inverter can last for longer duration’s and provide uninterrupted power supply to the user. Hybrid inverters are commonly used in the developing world, but they are starting to make their way into daily use in certain areas of the U.S due to their ability to stabilize energy availability. A solar inverter’s main job is to convert DC power generated from the array into usable AC power. Hybrid inverters go a step further and work with batteries to store excess power as well. This type of system solves issues renewable energy variability and unreliable grid structures. “Inverters for grid-tied applications can only provide power based on what the array can immediately generate from the sun,” explained Bryan Whitton, product manager at Darfon. “Hybrid inverters can store power in batteries and then drawn upon it as needed for energy stabilization.” Hybrid inverters can vary in size, performance and features. But Mara White, product manager for OutBack Power, said most models usually operate bi-directionally, meaning they can convert DC power from modules to usable AC power and then convert stored AC from the batteries to power loads when needed. “Hybrids can also remain grid-connected and use a mix of renewable and non-renewable energy to charge batteries and offset loads,” White added. Some contractors have used hybrid inverters in the residential, remote home applications for the past decade or two. But Allan Gregg, VP of applications engineering at GreatWall—which manufactures Satcon inverters—said the range of applications has expanded over the past few years to include large capacity microgrids as well as grid-connected systems. Historically, hybrid inverters have been used more frequently in developing countries that do not have access to a reliable power grid. “In North America and Europe, hybrid inverter-based systems are usually elective,” White explained. “Users choose to use them for storing energy for self-consumption or provide back-up power during emergencies. But in the developing world, hybrids are more of a necessity to compensate for weak or intermittent grids or a lack of grid electricity all together. Microgrids in places such as India, Asia and Africa are also driving na hybrid inverter hv adaptation.” Still, Whitton said hybrid models are beginning to be used on a more daily basis in areas of the U.S. where the grid is unpredictable, such as Hawaii, or in states where net-metering has been widely supported. “Applications with less than ideal solar characteristic are also good for hybrid-based systems because they can store power and redistribute it during peak times, improving payback,” he added. “Basically, if the site has the potential for losing the grid frequently, you should consider a hybrid for off-grid operation.” Having the flexibility of a hybrid system can add initial cost to a project, though experts say this can be offset by the ability to self-consume all of one’s available PV electricity. There are also important design considerations when using hybrid inverters. For example, Gregg warned that the battery bank voltage should be compatible with the DC input requirements of the inverter, and there should be enough solar capacity to supply the load as well as charge the batteries. Wiring can also be more complex when using hybrid inverters, especially when panels are dedicated for critical backed-up loads. “And as with any device that does several jobs at once, a hybrid inverter is usually slightly less efficient,” White added, “although, improvements in other balance-of-system components can compensate for that slight loss easily.” There are also specific electrical safety issues with any type of energy storage, so White recommended getting specialized training in energy storage techniques and design. “Most available training is focused on simple grid-tied systems because they have been the majority of U.S. solar installations until now,” she said. “But with incentives changing and the surge in energy storage interest and applications, it’s important to get ahead of the curve and get advanced training quickly.” Andrew McCalla of Austin, Texas-based Meridian Solar, a Solar Power World top contractor, said he commonly used hybrids in the mid to late ’90s when the now standard grid-tie inverter sector was just a glimmer. “I can imagine that, when regulatory hurdles are fabricated to limit the consumer and societal benefits of bi-directional power flow from distributed generation, these battery-based platforms will become far more common. What is old is new again!” Another segment of hybrid inverters includes inverters that can use two energy sources. For example, Ginlong offers a PV / wind lv battery hybrid inverter that has inputs for both sources, instead of having to use two inverters. In much of the United States, wind speeds are low in the summer when the sun shines brightest and longest. The wind is strong in the winter when less sunlight is available. Therefore, because the peak operating times for wind and solar systems occur at different times of the day and year, such hybrid systems have the potential to produce power when it’s needed, and reach a higher return on investment. When you first consider getting solar or battery storage on your home or business, one of the first things you will discover is that you will require an inverter and that there are many different types of inverters available. This article is designed to provide an introduction to the different kinds of inverters available and help you to understand which one will suit your installation. So what does an inverter do? Simply put an Inverter converts DC power to AC power. Solar panels produce DC power and batteries store DC, however most of our appliances run on AC power, as does the electricity grid. This is why all solar systems and battery storage systems need an inverter however there are several different types of inverters depending on whether or not energy storage batteries are required. On-grid solar installations are the most common and most affordable type of system available at present. These systems use a simple solar inverter, which convert the DC power from your solar panels into AC power which can be fed directly into the grid, or used in your home appliances. Off-grid and hybrid systems are much more complex because they involve both solar panels as well as battery storage. Multiple inverters are often required in these installations such as a solar inverter and sophisticated battery inverter/charger to manage both grid connection and the charging and discharging of the batteries. These advanced inverter/chargers are known as interactive or multi-mode inverters. However, in recent years a new type of inverter has become available which integrates solar and battery inverter technology into what is known as an all-in-one hv battery hybrid inverter. A micro-inverter is a very small inverter that is attached to the back of a solar panel. A micro-inverter only converts the power of one or two solar panels to AC so generally many microinverters are required in a single system. Micro-inverters have several advantages over string inverters including performance, safety and monitoring, however the upfront cost can be significantly greater. For more details about micro-inverters, check out our micro-inverters article. String solar inverters come in single phase and three phase versions although most residential homes in the US and Australia use single phase power, while many homes in Europe use 3-phase power, also all businesses and factories will have three phase power. As a general rule most String solar inverters between 1-6kW are single phase and greater than 6kW are usually three phase. As home energy storage systems have surged in popularity a new kind of advanced Inverter has emerged known as an hybrid inverter. Hybrid inverters combines a solar inverter and battery inverter/charger into one simple unit. These inverters are a very economical way to enable what is known as ‘self-use’ or 'load shifting' of energy. Allowing you to store solar or off-peak energy in a battery to be used during peak times. Although it is important to know that some all-in-one inverters cannot function during a power outage such as when there is a blackout. They can also have limited functionality and monitoring capabilities.The traditional off-grid solar system uses a simple battery inverter that converters DC power from a battery bank to AC power to supply your home or appliances, these systems need separate battery chargers and regulators. There are more advanced versions of these battery inverters with built in chargers known as inverter/chargers. In recent years very advanced inverters have become available which are inverter/chargers with in-built generator control systems, advanced monitoring capabilities and other features, these are known as interactive or multi-mode inverters. They are typically used in conjunction with a solar inverter to create what is known as an AC coupled system. You can learn more about these and other hybrid inverter types here.
Publish Date: 17-09-21
Description: The sink and faucet area is one of the most-used in any kitchen, and are often treated as a design focal point for the room. Upgrading your kitchen faucet is an easy and economical way to give your space a quick design refresh, or complement a whole kitchen transformation. A new faucet changes the look of the whole space. Be smart about the choice so that you find the best fit for your home and know what to look for before you buy. It’s no surprise that the kitchen faucet is one of the most well used items in the room, but what might be news is how many improvements have been made to this simple fixture. There are many more options than just the selection of comfortable handles for the hot and cold water lines. It’s a good idea to explore the different styles, finishes, and features that are available when selecting a new faucet. The right design will look great for years, and add to the value of your home - all while meeting the demands of your busy kitchen. Take a broader view of what the options are and bring home the best fit. Before you shop, it’s helpful to have an idea of what you want the end result to look like. Take stock of the styles and colors you want to emphasize and accent in your kitchen, as well as the size of your sink and countertop to compare as you consider a new faucet. The most important part about choosing a new faucet is that you be happy with the new addition to your kitchen after the installation, so always keep the final product in mind as you browse. Grab the measuring tape, because it’s time to get some numbers. It’s usually easier to find a faucet that works in the space allowed than it would be to rebuild the kitchen to accommodate a faucet. As with all home improvement projects, picking a new faucet requires some educated placement decisions, a general idea of what you want the finished sink area to look like, and the scope of the tasks it will be used for. This means you should know how wide and deep the basin is, especially in comparison to the size of plates, pots, and pans you plan to wash in the sink. Any faucet you buy will need to have a high enough spout for these chores and others, as well as a low enough placement to avoid excess splashing that will make a mess outside of the sink. Similarly, if you are looking at a deck-mounted faucet, know how much room is available behind the sink to install the faucet. A wall-mounted faucet needs to be placed with the spout extending over the center of the sink, which requires taking into account the space between the interior edge of the sink and the wall. For that, you will compare the sink measurements to the size of the faucets as you narrow down the selection. Measure the countertop behind the sink, and the diameter of the pre-drilled holes and the distance between their centers. You will need to know the width of the sink as well as the depth between the wall and sink edge. This is important for both the installation and the regular use of your faucet, as you’ll need to be sure there is room between the wall and faucet to fully articulate the faucet handles or levers. As you search for a new kitchen faucet, you’ll see a number of other options to choose from that influence the overall style and operation of the faucet in your home. It’s a good idea to understand the basic configurations before you choose, to be aware of the product information and ensure you get exactly the features you want. In a counter- or deck-mounted installation, drinking faucets can be mounted on the counter or sink edge. Deck mounted is the more common style, and it helps draw attention to the sink as a design element in your kitchen. Here you’ll find the largest variety of faucets, ranging from single-hole mounts to up to three-hole mounts, in all sizes and finishes. Wall mounted kitchen faucets are often found in more commercial or industrial locations, with a unique and modern style. Home kitchens, laundry rooms, garages, and greenhouses often rely on wall-mounted faucets for their space-saving design. In smaller kitchens with limited counter space, wall mounted faucets free up the counter and allow different design options for the sink, and unique plumbing profile lines. Valves regulate water flow and temperature from the faucets. They’re the basic control inside the faucet body that makes the water pour from the spout and aerator, turning on or off at your command with the turn of a handle. The different valve types work differently, which changes the capabilities of the design, and it also means that they require different kinds of maintenance over the long term. The valve type often describes the basic operation of the faucet, naming the moving parts that stop the water from leaking. There are many types, but there are four that are more common to come across. Ball valve - A ball valve is recognized by the single handle near the base that can control the water flow and the water temperature by pivoting and rotating to blend the water as needed. Disk valve - A ceramic disk valve faucet handle can move up and down to control the flow of the water, and side to side to control the amount of hot or cold in the mix. It gets the name from the two flat disks inside the faucet mechanisms that create the seal to control the water flow; moving the handle will separate the disks and allow the water through to the spigot. The disk valve can be replaced without replacing the entire faucet. Cartridge valve - Cartridge valves are hollow valves that are often found in faucets with blade handles because they only need turned to as much as a 90-degree angle to work. The cartridge rotates to block the water line to the spout. For a single handle faucet, the cartridge moving up and down will allow the water flow, and turning the handle left to right will control the temperature. When there are separate handles, such as in a three or four hole sink set up, two individual handles can control the hot and cold water lines separately to mix in the faucet. Cartridges can be replaced without needing to replace the entire faucet. Compression valve - A compression valve is usually found in older fixture styles. They look like the traditional faucet, with the 360 degree, turn-screw, knob handles. Hot and cold water are managed by separate handles, and in more vintage set ups, they can be routed to different taps as well. Turning the handles will tighten or loosen an internal washer, and that compression closes the water line. Because of how they are built, a busted compression valve will often require replacing the whole faucet rather than a few internal pieces. If your sink is a drop-in, undermount, or farmhouse design, it is likely to have a set of holes drilled or pre-punched into the deck for the faucet and other plumbing fixtures. The faucet itself can take up as many as 3 holes, depending on the type of faucet you choose, and other fixtures like soap dispensers can be installed for your convenience, too. Whether you will choose one hole, two, or even four holes along the sink deck depends on the kind of look or style that you want as much as the kind of faucet you choose. Single-hole faucet with a pull-down sprayer - These can include the high, gooseneck faucets with the tall, drastic arch leading to the spout, as well as the more industrial-style pre-rinse faucet with the durable springs and lever handle along the spray-hose for added reach and control. Others mount the handle on the faucet body, while touchless models require no handle at all; just wave at the side-mounted sensor, or for tomorrow’s kitchens, give a voice command to start up the water. Single-hole faucet with a side-spray - While it may be a single hole faucet, the smaller side spray will occupy a second hole pre-drilled in the sink deck or countertop. This is a simple, clean look that doesn’t take up too much extra room on the deck and offers versatility and utility. Two-hole escutcheon plates are available to accent the design, or to cover up a third hole in the sink that might not be needed. Two-handle faucet (3-hole layout) - To emphasize the artistic design of a faucet, some fixtures will have hot and cold water as separate handles, one on each side of the center faucet. It visually helps take up a little extra space along the sink edge and draws attention as a design focal point. They are also very easy to use while doing the usual sink-based chores, with one-handed hot or cold water at the turn of a handle. An escutcheon plate cover can also be utilized cover one of three holes, to allow a faucet with a single, separate control handle. Bridge faucet with side spray (4-hole layout) - A bridge faucet will have two temperature handles alongside a center water flow pipe. The hot and cold water will travel up their dedicated handles and then mix in the connection between them on the way to the spout. A bridge faucet can take up three holes or two, depending on the style you choose, and will usually require a separate side spray as the bridge connection prevents the extending hose feature. There isn’t much to be done with a stainless sink faucet; the entire purpose of it is as a water source, and the water is either on or off, right? Not exactly. The shape of the faucet changes from one design to another, and companies like Moen, Delta, Brizo, and Kohler are constantly looking to improve how the kitchen faucet interacts in the home. It started with the basics, like the side spray and the pull-down faucet. Now, technology-savvy companies have even wondered: why should you have to dirty up the finish with soapy fingerprints when waving a plate under the faucet could turn the water on? And their ideas and solutions improve year after year, all to make the kitchen life a little easier with a wide variety of standard features to choose from. Side sprayer - A classic staple at the kitchen sink was the side sprayer. The smaller faucet is located at the end of an extendable hose, offering directed water pressure exactly where it is needed, whether cleaning the pots and pans, scrubbing the sink, or watering a potted plant. Pull-out faucet - The pullout faucet offers all the convenience of the side sprayer without taking up any extra space on the sink edge. The hose extends down toward the sink or at an angle just above it, which adds a slight advantage in reach. Electronic faucet features - A growing trend in today’s homes is the addition of smart technology, computerized mechanics that help make the everyday chores a little easier. The kitchen sink can now be turned on and off with the wave of a hand thanks to motion sensor technology installed in the faucet body. Other designs include the ability to control the sink by talking to it, taking hands-free activation a step further with voice-activation. Electronic features are safe and convenient, but they may require professional installation. Sinks with electronic features will need to be installed with access to a reliable power supply, so keep their placement in mind during your kitchen remodel plans. Water filtering - Some kitchen faucets are available with built-in filtration options that can purify your tap water to make it drinkable, right from the faucet. These high-capacity faucets are capable of delivering as much as 1GPM of water, filtering out common problem chemicals like chlorine, lead, mercury, and even pesticides and pharmaceuticals. Drinking water dispensers - Whether filtered and cold, or ready for cocoa or tea, dedicated drinking water dispensers can be installed at the sink. They are sized to fit in the same holes that a regular kitchen faucet would use, but they are designed to pour water at a slower rate, more appropriate for filling drinking cups. They are usually found as part of a filter kit, and many include hot water dispensers that store and maintain water at a drinkable temperature just right for tea. Finally, one of the most important details when selecting a brushed stainless kitchen faucet is choosing the perfect finish. The finish determines the color and durability of the faucet for years to come. From stainless steel, to copper, to modern black, the finish can be found in a variety of metals and colors to coordinate with the accenting colors of your kitchen hardware and appliances. Newer finishes are designed specifically to resist the oils of fingerprints and smudges, making it easier to keep clean and helping to keep your family healthy. As it turns out, it’s even okay to mix metals in your home decor, so go with the style that you like. Chrome is currently one of the most popular finishes because of its versatility. It is durable, easy to find, and easy to match with accessories and other fixtures. A brushed nickel finish is very durable, keeping its finish longer and resisting wear and tear. Copper finishes provide a bold and rich feel to your space. With the ability to ‘heal itself’, the more it gets used, the better it looks. If you’re looking for a good balance of durability and style, you can’t go wrong with stainless steel. At the end of the day, make sure you pick a faucet that works with your style. While some finishes tend to be more durable than others, on the whole, most finishes will stand the test of every-day wear and tear. So really focus on style here, and find something that matches your space.
Publish Date: 16-09-21
Description: When it comes to gifting things to the people we love, we are sure you won’t feel any surprise at all to learn that we’re massive fans of making things ourselves whenever we can. Of course, we also value the thought that goes into store bought gifts, whether we are giving or receiving, but we just get such a great sense of satisfaction watching our friends and family’s faces light up when they open something we made for them ourselves! Sometimes, however, a gift that we purchased rather than something we made is simply the best idea, but that does not mean we can not get crafty with the gifting process in some capacity. Lately, we have been completely obsessed with the idea of making our own gift wrap, particularly when it comes to gift boxes! If you are going to go to the trouble of making DIY gift set and homemade gift box, would you rather go all out and make it incredibly special, like something the recipient might want to keep and continue to use? Then we’d absolutely suggest taking a look at how creative ideas made this stunning closing box features layered tiers for different gifts and trinkets. Besides that useful feature, the way they decorated the outside of the box with lace, pearls, and flowers is nothing short of gorgeous! If we received this box, we’d use it as a jewelry box and place it on our dresser. By now you’ve probably seen one of the most popular trends for coloring hair: hair chalk! From runways and music festivals to Halloween and fun nights out with friends, hair chalk is a go-to for adding a quick dab of color to hair both easily and affordably. Hair chalk pen is a stick of color, similar to regular chalk, but is given its color by mixing a variety of ingredients together. While hairstylists and suppliers have their own process of making it, the typical ingredients are mixed with dry pigment, some chalk, and a binder, according to Thaneeya McArdle, a pastel artist at Art Is Fun. While you theoretically could use regular chalk on your hair, it wouldn’t have the same colorful effect or work the same way chalk made specifically for hair works. Whether it is occupying the kids during school holidays with rock painting or just decorating everyday household possessions, acrylic paint marker pens have huge appeal. In fact, some prefer them over traditional artist acrylic painting using a brush and palette. Why is this so? And what makes a good acrylic paint pen set? You will have come across oil-based paint pens if you’ve ever used a pen where you have to vigorously shake the pen so the ball bearing can mix the paint with the oil before use. Being oil solvent based, these markers leave a strong odour and are, therefore, not ideal for (or around) children or for use in poorly ventilated areas. Oil-based markers will take much longer to dry than acrylic ones. Though they can be used on similar surfaces to their acrylic counterparts, oil-based markers will behave slightly differently. The paint tends to sit slightly better on porous surfaces and offers the advantage of not having to be ‘sealed’ (more on this later). That said, on non-porous surfaces, such as paper and card, they are more susceptible to bleeding on the surface. Acrylic is a favored painting medium for both beginners and professionals alike for its easy setup, quick-drying properties, and malleable nature. Made out of pigments suspended in acrylic polymer, acrylic paint is water-soluble but becomes water-resistant when dry. A highly flexible paint medium, acrylic will provide a crisp, graphic paint edge that can be easily used to create thick paint strokes or thin washes, and it is suitable for use on a wide range of surfaces. Depending on your project ambitions, you will want to consider key factors such as color saturation and selection, permanence and finish, as well as viscosity and malleability. Our picks below will help you find the right acrylic paint set for your needs. For beginners looking to hone their acrylic painting skills, this acrylic paint set of two dozen 12-milliliter tubes of paint from Colore is ideal. Providing an excellent selection of colors, this student-grade paint is suitable for use on a wide range of surfaces including canvas, paint, wood, fabric, and rock. Featuring a smooth texture for easy blending, this paint is quick drying and durable, with a glossy finish. Liquid chalk sets are small but mighty. They can be used for a wide range of purposes, varying from decoration to personal or even business purposes.
Publish Date: 14-09-21