"Them Changes" ballasts surreal horror with goofy mouth sound basslines.
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Instead, it ballasts the most outrageous twists with realistic emotional responses.
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The oldest plants on earth serve as modest ballasts in floral arrangements, as well as in life.
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The songs are pared back and essential, the impish creaks are replaced with steady ballasts of earned sadness.
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Buddhima Indraratna, an engineering professor specializing in railway geotechnology, said the trackbeds, known as ballasts, would have been infected.
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Friday's edition of the Federal Register contains new rules for smart guns, underground coal mines and fluorescent lamp ballasts.
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The GBS platforms will be located near the Arctic Ocean coast and held in place on the seabed by ballasts.
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Here's what is happening: Fluorescent lamps: The Department of Energy is moving forward with new efficiency rules for fluorescent lamp ballasts.
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Heat-related expansion places a lot of stress on the ties, ballasts, and rail anchors that keep the tracks fixed to the ground.
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"The ballasts are now probably contaminated with landslide mud and debri; fouled ballast needs to be replaced, or cleaned and placed again," Indraratna said.
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The speed they switch on depends on the type of bulb and the intervening mechanisms like transformers, ballasts and drivers that may be present.
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Apart from the low thunder of airport traffic, the loudest sound in Hangar 212 is the buzz of fluorescent ballasts, echoing around the 1.8-acre structure.
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McFerren, never one to pass up a good gag, ballasts even these minor key excursions with the delicate punch of a goofy glissando and other lighthearted sounds.
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The Duplasses, who have for a long while served as ballasts and champions of indie filmmaking, created a pipeline with this show to bring new voices to HBO.
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Maybe they arrived in the water used for ships' ballasts, or as polyps attached to barnacles on ships' hulls; in shellfish imports, or perhaps they drifted across the Arctic Ocean.
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Zink's narrative is propulsive, wonderfully stuffed with irreverent and absorbing banter among these characters who move in slightly off-kilter orbits, as if their wills are counterweighed by ballasts of personal history that we can only guess at.
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A second Oscar nomination followed for "Doubt" in 2009, in which her credible innocence as the nun Sister James, opposite Meryl Streep and Philip Seymour Hoffman in scathing battle, ballasts a story about the thin line between human nature and the abyss.
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This design phase is also where the team starts to do the math to figure out aerodynamics and volume coefficients to know just how much helium and heavier air ballasts they'll need to float a giant, 450-pound Charlie Brown and his 30-foot kite.
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The book leaves us wanting more in the way of suggested regulations, but by laying out the terrain so thoughtfully, and highlighting the concepts that should guide our actions, Jones has created the groundwork for a much needed conversation on the profound problem of permanent digital ballasts in the 21st century.
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An HMI ballast To power an HMI bulb, special ballasts act as an ignitor to start the arc, and then regulate it by acting as a choke. Two types of ballasts exist: magnetic and electronic (square-wave or flicker-free). Magnetic ballasts are generally much heavier and bulkier than electronic ballasts, as they consist primarily of a network of large inductors. They are usually cheaper than electronic ballasts.
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In ballasts that control two or more lamps, line-frequency ballasts commonly use different phase relationships between the multiple lamps. This not only mitigates the flicker of the individual lamps, it also helps maintain a high power factor. These ballasts are often called lead-lag ballasts because the current in one lamp leads the mains phase and the current in the other lamp lags the mains phase. In most 220-240V ballasts, the capacitor isn't incorporated inside the ballast like in North American ballasts, but is wired in parallel or in series to the ballast.
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The 100–120 Hz flicker produced by magnetic ballasts is associated with headaches and eyestrain. Individuals with high critical flicker fusion threshold are particularly affected by light from fluorescent fixtures that have magnetic ballasts: their EEG alpha waves are markedly attenuated and they perform office tasks with greater speed and decreased accuracy. The problems are not observed with electronic ballasts. Ordinary people have better reading performance using high-frequency (20–60 kHz) electronic ballasts than magnetic ballasts, although the effect was small except at high contrast ratio.
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Magnetic ballasts are usually filled with a tar-like potting compound to reduce emitted noise. Hum is eliminated in lamps with a high-frequency electronic ballast. Energy lost in magnetic ballasts is around 10% of lamp input power according to GE literature from 1978. Electronic ballasts reduce this loss.
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Simple inductive fluorescent lamp ballasts have a power factor of less than unity. Inductive ballasts include power factor correction capacitors. Simple electronic ballasts may also have low power factor due to their rectifier input stage. Fluorescent lamps are a non-linear load and generate harmonic currents in the electrical power supply.
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Some magnetic ballasts have insulation around the coil for silent operation. Since the early 1990s, electronic flicker-free (or Square-Wave) ballasts have become increasingly popular and affordable as an alternative to magnetic ballasts by eliminating most of the problems associated with HMI flicker. Unfortunately, their operation is not as simple as a magnetic ballast. Electronic ballasts can be thought of as operating in three stages—a DC intermediate converter, a power module, and an AC inverter.
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Series resistors are used as ballasts to control the current through LEDs.
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The "beat effect" problem created when shooting films under standard fluorescent lighting Electromagnetic ballasts may also cause problems for video recording as there can be a so-called beat effect between the video frame rate and the fluctuations in intensity of the fluorescent lamp. Fluorescent lamps with electronic ballasts do not flicker, since above about 5 kHz, the excited electron state half-life is longer than a half cycle, and light production becomes continuous. Operating frequencies of electronic ballasts are selected to avoid interference with infrared remote controls. Poor quality or faulty electronic ballasts may have considerable 100/120 Hz modulation of the light.
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The high output frequency of an electronic ballast refreshes the phosphors in a fluorescent lamp so rapidly that there is no perceptible flicker. The flicker index, used for measuring perceptible light modulation, has a range from 0.00 to 1.00, with 0 indicating the lowest possibility of flickering and 1 indicating the highest. Lamps operated on magnetic ballasts have a flicker index between 0.04–0.07 while digital ballasts have a flicker index of below 0.01.Specifier Reports: Electronic Ballasts p.
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Application of electronic ballasts to HID lighting is growing in popularity. Most newer generation electronic ballasts can operate both high pressure sodium (HPS) lamps as well as metal-halide lamps, reducing costs for building managers who use both types of lamps. The ballast initially works as a starter for the arc, supplying a high-voltage impulse and, later, it works as a limiter/regulator of the electric flow inside the circuit. Electronic ballasts also run much cooler and are lighter than their magnetic counterparts.
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IEC 60929 is an international standard created by the International Electrotechnical Commission and covers electronic ballasts used in AC supplies with voltages up to 1000 V and with operating frequencies at 50 Hz or 60 Hz. The actual operating frequency may deviate from the specified supply frequency. The standard essentially covers the same material as IEC 60921, but it is considerably more complex due to the high frequency aspect of electronic ballasts. Appendix E of the standard defines the DALI, which specifies how ballasts are controlled.
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Each module would, via support columns, be atop two pontoons which would contain ballasts. When travelling, the module would sail along the surface of the water via its pontoons. When stationary, the ballasts are filled and the pontoons are submerged, leaving the platform still above the waterline. This helps keep the module stable.
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An inductor is very common in line-frequency ballasts to provide the proper starting and operating electrical condition to power a fluorescent lamp, neon lamp, or HID lamp. (Because of the use of the inductor, such ballasts are usually called magnetic ballasts.) The inductor has two benefits: # Its reactance limits the power available to the lamp with only minimal power losses in the inductor # The voltage spike produced when current through the inductor is rapidly interrupted is used in some circuits to first strike the arc in the lamp. A disadvantage of the inductor is that current is shifted out of phase with the voltage, producing a poor power factor. In more expensive ballasts, a capacitor is often paired with the inductor to correct the power factor.
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Advanced electronic ballasts may allow dimming via pulse-width modulation or via changing the frequency to a higher value. Ballasts incorporating a microcontroller (digital ballasts) may offer remote control and monitoring via networks such as LonWorks, Digital Addressable Lighting Interface (DALI), DMX512, Digital Serial Interface (DSI) or simple analog control using a 0-10 V DC brightness control signal. Systems with remote control of light level via a wireless mesh network have been introduced. Electronic ballast of a compact fluorescent lamp Electronic ballasts usually supply power to the lamp at a frequency of or higher, rather than the mains frequency of ; this substantially eliminates the stroboscopic effect of flicker, a product of the line frequency associated with fluorescent lighting (see photosensitive epilepsy).
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These ballasts convert the incoming power to an output frequency in excess of . This increases lamp efficiency. These ballasts operate with voltages that can be almost 600 volts, requiring some consideration in housing design, and can cause a minor limitation in the length of the wire leads from the ballast to the lamp ends.
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Quick-start ballasts are more common in commercial installations because of lower maintenance costs. A quick-start ballast eliminates the need for a starter switch, a common source of lamp failures. Nonetheless, Quick-start ballasts are also used in domestic (residential) installations because of the desirable feature that a Quick-start ballast light turns on nearly immediately after power is applied (when a switch is turned on). Quick-start ballasts are used only on 240 V circuits and are designed for use with the older, less efficient T12 tubes.
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In addition to solving the problems of flicker, electronic ballasts also provide other advantages over magnetic ballasts. With a square wave voltage, the cathodes spend much more time emitting electrons and exciting the plasma, creating a gain of 5–10% in lumen output.IES Lighting Handbook 1984 The square-wave nature of the power flow allows lamp life to be extended by as much as 20%. Most modern ballasts are now also equipped with a dimmer, which uses pulse-width modulation to dim the lamp up to 50%, or as much as one stop of light.
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Used in high end electronic fluorescent ballasts. This ballast applies power to the filaments first, it allows the cathodes to preheat and then applies voltage to the lamps to strike an arc. Lamp life typically operates up to 100,000 on/off cycles when using programmed start ballasts. Once started, filament voltage is reduced to increase operating efficiency.
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A hybrid ballast has a magnetic core-and-coil transformer and an electronic switch for the electrode-heating circuit. Like a magnetic ballast, a hybrid unit operates at line power frequency—50 Hz in Europe, for example. These types of ballasts, which are also referred to as cathode-disconnect ballasts, disconnect the electrode-heating circuit after they start the lamps.
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This means its resistance decreases as the current through the tube increases. So if the lamp is connected directly to a constant-voltage source like the power lines, the current through it will increase until it destroys itself. Therefore, it requires a ballast to limit the current through it. Mercury vapor lamp ballasts are similar to the ballasts used with fluorescent lamps.
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For HMI lamps, flicker can be avoided by the use of electronic ballasts that cycle at frequencies thousands of times faster than the mains frequency.
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The ballast adds positive impedance (AC resistance) to the circuit to counteract the negative resistance of the tube, limiting the current. alt= A magnetic sign ballast in an aluminum sign frame. Sign ballasts are heavier duty than other ballasts because the cooler outdoor temperatures increase the energy required to start a fluorescent tube. They are sized based on how many feet of tube is used.
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Fluorescent & discharge lighting is more efficient than incandescent lighting. Fluorescent lighting with conventional magnetic ballasts will see a reduced power consumption, but also a reduced lumen output from the lamp. Fluorescent lamps on modern electronic ballasts will use approximately the same power and give the same light. To provide the same wattage at the reduced voltage will require a greater current and increase cable losses.
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Fishermen noticed an increase of tankers, shipping traffic, and risks of collision as more ballasts were being dumped into sea, resulting in pollution and less fish.
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Isabel Ballasts Becker (born 1974) is a German-Spanish scientist and chemist on the faculty of biochemistry in the medical department at the Autonomous University of Madrid.
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These new ballasts operate at voltages up to 600 V AC, and at 20,000 Hz, with some high frequency ballasts operating as high as 100,000 Hz or higher. This allows the ballast to energize the lamp with more than raw power, and instead operates using a combination of electrical force and induction. This allows a 100 watt lamp to fully light with as little as 65 watts. S12 lamp starter.
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Low pressure sodium lamps operate this way. The simplest ballasts are just an inductor, and are chosen where cost is the deciding factor, such as street lighting. More advanced electronic ballasts may be designed to maintain constant light output over the life of the lamp, may drive the lamp with a square wave to maintain completely flicker-free output, and shut down in the event of certain faults.
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A choke ballast (inductor) used in older lighting. This example is from a tanning bed. It requires a starter switch (below). lamp starter, required with some inductor type ballasts.
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When the AC period is shorter than the relaxation time to de-ionize mercury atoms in the discharge column, the discharge stays closer to optimum operating condition. Electronic ballasts convert supply frequency AC power to variable frequency AC. The conversion can reduce lamp brightness modulation at twice the power supply frequency. Low cost ballasts contain only a simple oscillator and series resonant LC circuit. This principle is called the current resonant inverter circuit.
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The flicker of fluorescent lamps, even with magnetic ballasts, is so rapid that it is unlikely to present a hazard to individuals with epilepsy. Early studies suspected a relationship between the flickering of fluorescent lamps with magnetic ballasts and repetitive movement in autistic children. However, these studies had interpretive problems and have not been replicated. LED lamps generally do not benefit from flicker attenuation through phosphor persistence, the notable exception being white LEDs.
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The adapter consists of a regular bulb screw, the ballast itself and a clip for the lamp's connector. Non-integrated bi-pin double-turn CFL with G24d plug-in base An electronic ballast and permanently attached tube in an integrated CFL CFLs have two main components: a magnetic or electronic ballast and a gas-filled tube (also called bulb or burner). Replacement of magnetic ballasts with electronic ballasts has removed most of the flickering and slow starting traditionally associated with fluorescent lighting, and has allowed the development of smaller lamps directly interchangeable with more sizes of incandescent light bulb. Electronic ballasts contain a small circuit board with a bridge rectifier, a filter capacitor and usually two switching transistors, which are often insulated-gate bipolar transistors.
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The output frequency is started above the resonance frequency of the output circuit of the ballast; and after the filaments are heated, the frequency is rapidly decreased. If the frequency approaches the resonant frequency of the ballast, the output voltage will increase so much that the lamp will ignite. If the lamp does not ignite, an electronic circuit stops the operation of the ballast. Many electronic ballasts are controlled by a microcontroller, and these are sometimes called digital ballasts.
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In the EU the use of low efficiency mercury vapor lamps for lighting purposes was banned in 2015. It does not affect the use of mercury in compact fluorescent lamp, nor the use of mercury lamps for purposes other than lighting.Phasing out of mercury vapor lamps. www.osram.co.uk. Retrieved on 2015-03-18. In the US, ballasts for mercury vapor lamps for general illumination, excluding specialty application mercury vapor lamp ballasts, were banned after January 1, 2008.
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Fluorescent lamps are (almost) never operated directly from DC for those reasons. Instead, an inverter converts the DC into AC and provides the current-limiting function as described below for electronic ballasts.
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It is also very apparent with dimming ballasts. The inverse is true for an overpowered bulb, but this condition can be hazardous, leading possibly to arc-tube explosion because of overheating and overpressure.
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Electronic starters are not subject to wear and do not need replacing periodically, although they may fail like any other electronic circuit. Manufacturers typically quote lives of 20 years, or as long as the light fitting. Electronic ballasts employ transistors to change the supply frequency into high-frequency AC while regulating the current flow in the lamp. These ballasts take advantage of the higher efficacy of lamps, which rises by almost 10% at , compared to efficacy at normal power frequency.
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Conversion bulbs are manufactured so they work with either a MH or HPS ballast. A grower can run an HPS conversion bulb on a MH ballast, or a MH conversion bulb on a HPS ballast. The difference between the ballasts is an HPS ballast has an igniter which ignites the sodium in an HPS bulb, while a MH ballast does not. Because of this, all electrical ballasts can fire MH bulbs, but only a Switchable or HPS ballast can fire an HPS bulb without a conversion bulb.
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Flicker is also important in the field of domestic (alternating current) lighting, where noticeable flicker can be caused by varying electrical loads, and hence can be very disturbing to electric utility customers. Most electricity providers have maximum flicker limits that they try to meet for domestic customers. Fluorescent lamps using conventional magnetic ballasts flicker at twice the supply frequency. Electronic ballasts do not produce light flicker since the phosphor persistence is longer than a half cycle of the higher operation frequency of 20 kHz.
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The disadvantage of the newer electronics is price. It can cost 3 to 5 times more per lamp to use electronic ballasts than traditional choke ballasts, which is why choke ballasts are still used in the majority of new tanning systems. Another disadvantage of the older style choke ballast is they are designed for European electricity, and require incoming voltage in the range of 220 V AC and 230 V AC. Most US homes have 110 V service and businesses use 208 V three-phase service that requires these beds to use a buck-boost transformer in order to receive the proper voltage. Too low a voltage will result in the lamp starter not letting the lamp ignite (or at the least, very slowly) whereas too high a voltage can lead to premature failure in the starters and lamps.
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For a lighting ballast, the ANSI ballast factor is used in North America to compare the light output (in lumens) of a lamp operated on a ballast compared to the lamp operating on an ANSI reference ballast. Reference ballast operates the lamp at its ANSI specified nominal power rating.IEEE Std. 100 "Dictionary of IEEE Standards Terms, Standard 100" , , page 83ANSI standard C82.13-2002 "Definitions for Fluorescent Lamp Ballasts", page 1 The ballast factor of practical ballasts must be considered in lighting design; a low ballast factor may save energy, but will produce less light.
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Digital ballasts can apply quite complex logic to lamp starting and operation. This enables functions such as testing for broken electrodes and missing tubes before attempting to start, detection of tube replacement, and detection of tube type, such that a single ballast can be used with several different tubes. Features such as dimming can be included in the embedded microcontroller software, and can be found in various manufacturers' products. Since introduction in the 1990s, high-frequency ballasts have been used in general lighting fixtures with either rapid start or pre-heat lamps.
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An application specific version (ASSP) of the RL78 core was introduced in 2012 for controlling lighting systems, this device was named the RL78/I1A. Specific features of the device such as special PWM timers enable fine dimming, lighting sequence and colour temperature control with power factor correction of the power supply. In addition integrated communication functions for DALI, DMX512 and multiple sensor & user interface controls are provided. Applications for the RL78/I1A include: building automation, LED drivers, lighting controls, fluorescent ballasts, emergency lighting, HID ballasts, digital power supplies, low-cost inverter controls.
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They commonly also produce acoustic noise (line-frequency hum). Prior to 1980 in the United States, polychlorinated biphenyl (PCB)-based oils were used as an insulating oil in many ballasts to provide cooling and electrical isolation (see Transformer oil).
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In newer buildings, the lighting control can be based on the field bus Digital Addressable Lighting Interface (DALI). Lamps with DALI ballasts are fully dimmable. DALI can also detect lamp and ballast failures on DALI luminaires and signals failures.
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The company also released its Zipline Fluorescent Energy Retrofit Module, which eliminated retrofit wiring of ballasts. Leviton acquired Home Automation Inc. in August 2012, and renamed it Leviton Security & Automation. In October 2013, Leviton acquired UK-based JCC Advanced Lighting.
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Mercury vapor fixtures can be operated with metal halide lamp (MH) ballasts, and are likely to be rewired with these ballasts in coming years. In response to the ban, some older MV streetlights will most likely be modified to use either high pressure sodium or metal halide lamps in the near future, because they are known to last longer than newer luminaires. In some areas where the MV lights are either failing or being replaced, they are being replaced by either HPS, LED, or Induction fixtures of similar lumen output, but also lower wattages and power consumption as well.
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They may be as simple as a resistor, inductor, or capacitor (or a combination of these) wired in series with the lamp; or as complex as the electronic ballasts used in compact fluorescent lamps (CFLs) and high-intensity discharge lamps (HID lamps).
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These systems require 230 V AC Schematic for HF Ballasts: It is much simpler as everything is self-contained. The main disadvantage is price, costing several times more than a choke ballast. They can be configured to run on 120 V or 230 V.
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Since the magnetic type of ballast does not maintain the discharge continuously, the lamp actually extinguishes at zero-crossings of the mains waveform; unless the camera is locked to the mains waveform, the difference in frequency between the lamp and the shutter will produce a beat frequency that is visible in the resulting recording. This is why TV standards typically use the power grid frequency as their basic frame rate. Magnetic ballasts are simple devices compared to electronic ballasts. Essentially, a magnetic ballast is a large, heavy transformer coil that uses a simple principle to generate the high startup voltages needed to create an arc in a cold lamp.
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Modern electronic ballasts usually change the frequency of the power from a standard mains frequency of 50 or 60 Hz up to 40 kHz or higher, often using a Switched Mode Power Supply (SMPS) circuit topology with Power Factor Correction (PFC). First the AC input power is rectified to DC, and then it is chopped at a high frequency to improve the power factor. In more expensive ballasts, a film capacitor is often paired with the inductor to correct the power factor. In the picture at right, the flat grey rectangular component in the middle of the ballast circuit is a polyester film capacitor used for PFC.
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In addition to general lighting, special fluorescent lights are often used in stage lighting for film and video production. They are cooler than traditional halogen light sources, and use high-frequency ballasts to prevent video flickering and high color-rendition index lamps to approximate daylight color temperatures.
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Australian tubeworms are introduced to new habitat when they are transported on ship hulls, in ballasts, and on shells. Management options are mainly limited to the prevention of new introductions. Methods include deoxygenating ballast water to kill larvae and simply scraping the tubes off of ships and other surfaces.
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Fluorescent lamps convert more of the input power to visible light than incandescent lamps. A typical 100 watt tungsten filament incandescent lamp may convert only 5% of its power input to visible white light (400–700 nm wavelength), whereas typical fluorescent lamps convert about 22% of the power input to visible white light. The efficacy of fluorescent tubes ranges from about 16 lumens per watt for a 4 watt tube with an ordinary ballast to over 100 lumens per watt with a modern electronic ballast, commonly averaging 50 to 67 lm/W overall. Ballast loss can be about 25% of the lamp power with magnetic ballasts, and around 10% with electronic ballasts.
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A square wave can be thought of as an infinite sum of odd-numbered harmonics, which will include frequencies at the resonant frequency of the bulb, causing it to vibrate at that frequency like a bell or whistle. The lamp housing does not help this, acting as a resonating chamber that amplifies the noise and presents a problem for sync-sound recording for film and video. To correct this, most electronic ballasts are equipped with a silent mode that eliminates the higher frequencies, but rounds off the voltage transition, causing the same flicker issue with magnetics, though to a lesser extent. This mode provides safe, flicker-free filming at framerates up to 24 frame/s on most electronic ballasts.
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The locomotives are a 6-axle Co'Co' twin cab design, incorporating a RK 215 engine with a power at rail of . After premature failures both in engine and turbocharger RAI has de-rated the engine power gradually up to 2400 Kw. Three variants were produced, a passenger version with a top speed and a axle load, and two freight versions with a top speed and either a axle load., Only two prototypes of ballasted locomotives had been introduced;as, the ballasts limited the engine room space and higher center of gravity raised concerns, the ballasts were later removed completely. The passenger locomotives were later assigned for freight service because of low reliability and introduction of more reliable ER24PC locomotives.
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FastTracks is a program intended to address the slow zones and to make train rides smoother and more reliable. In order to achieve this, crews would replace worn tracks, rail tires, and ballasts. An upgraded power system along the O'Hare Blue Line branch would enable more trains to operate during peak periods.
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The motors were overhauled, the batteries changed, and the pressure hulls and diving auxiliaries reinforced. The ballasts were also reworked to improve the range of the boats. Efforts were made to improve the soundproofing the submarines. The submarines were equipped with radar, underwater sound systems, better performing asdic, bathythermographs and other capabilities.
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The installed lighting density for artificial lighting is lower than that of a standard building. Indeed, highly efficient artificial lighting (6 W/m², 218 Btu/ft²) is used. Dimmable T5 tubes with electronic ballasts are provided for open office spaces and common areas. The LEDs are used as spotlights and for outdoor lighting.
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A CFL used outside of a building CFLs are generally not designed for outdoor use and some will not start in cold weather. CFLs are available with cold-weather ballasts, which may be rated to as low as −28.8 °C (−20 °F). Light output in the first few minutes drops at low temperatures.U.S. Dept.
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An electronic ballast with an integrated battery is designed to provide emergency egress lighting in the event of a power failure (typically less than 2 hours). These can be used as an alternative to egress lighting powered by a back-up electrical generator. However, emergency ballasts require regular testing and have a useful life of 10-12 years.
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A DALI network consists of at least one application controller, input devices (e.g. sensors and push-buttons), bus power supplies (which may be built into any of the products), control gear (e.g., electrical ballasts, LED drivers and dimmers) that have DALI interfaces. Application controllers can control, configure or query each device by means of a bi-directional data exchange.
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Die Zumtobel-Konzerngruppe von 1950–2000. LIT Verlag Münster, 2009, S. 24 f. (PDF; 60 kB), retrieved 23 September 2012 Zumtobel Group headquarters in Dornbirn, Austria Tridonic headquarters in Dornbirn, Austria Initially, the company primarily produced electrical ballasts for fluorescent light fittings. In 1952, the company started to manufacture complete luminaires based on fluorescent light fittings.
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A Sankey diagram of energy losses in a fluorescent lamp. In modern designs, the biggest loss is the quantum efficiency of converting high- energy UV photons to lower-energy visible light photons. Only a fraction of the electrical energy input into a lamp is converted to useful light. The ballast dissipates some heat; electronic ballasts may be around 90% efficient.
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Another proposed vector is that of foreign ships bringing in individuals via their ballasts. A final possibility proposed was that the individual specimens were intentionally released by aquarists. Diadema setosum is commonly associated with coral reefs, but is also found on sand flats and in seagrass beds. Along with the other members of the family, D. setosum is a prolific grazer.
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Newer electronic systems work differently and always treat one end of the lamp as a cathode and one end as an anode. Whereas the choke style always works at 230 V AC at 60 Hz (220–240 V AC/50 Hz in EuropeElectrical Power In Europe), newer electronics work very differently. This includes magnetic, pure solid state, and high frequency ballasts.
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Quick-start ballasts use a small auto-transformer to heat the filaments when power is first applied. When an arc strikes, the filament heating power is reduced and the tube will start within half a second. The auto-transformer is either combined with the ballast or may be a separate unit. Tubes need to be mounted near an earthed metal reflector in order for them to strike.
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To ensure close competition, each model of car was tested by the FIA to determine any mandatory adjustments (such as extra weight ballasts and restrictor tweaks) for performance balancing. Performance adjustments were also made between races during the season. To defray costs for individual teams, the SRO provided free transport for cars and equipment as well as airline tickets for ten personnel per team.
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To prevent this, a ballast provides a positive resistance or reactance that limits the current. The ballast provides for the proper operation of the negative-resistance device by limiting current. Ballasts can also be used simply to limit the current in an ordinary, positive-resistance circuit. Prior to the advent of solid-state ignition, automobile ignition systems commonly included a ballast resistor to regulate the voltage applied to the ignition system.
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The inductance of this winding limits the flow of AC current. This type is still used, for example, in 120 volt operated desk lamps using relatively short lamps. Ballasts are rated for the size of lamp and power frequency. Where the AC voltage is insufficient to start long fluorescent lamps, the ballast is often a step-up autotransformer with substantial leakage inductance (so as to limit the current flow).
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After a short time the voltage across the lamp reaches about 1 kV and the lamp instant-starts in cold cathode mode. The cathode filaments are still used for protection of the ballast from overheating if the lamp does not ignite. A few manufacturers use positive temperature coefficient (PTC) thermistors to disable instant starting and give some time to preheat the filaments. More complex electronic ballasts use programmed start.
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To facilitate the wheels of a locomotive, the rails projected two inches above the sleepers. Originally assumed to adopt a narrow gauge, a was later clarified to be favoured, standardising the railway line's gauge with those of light railways in India slated for construction beginning 1872. The railway also lacked ballasts as the Johor government was unable to afford them. Instead, the sleepers were embedded into the ground.
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On 27 June 1889, Chatterjee made his second solo ascent in 'The City of Calcutta' from Khusrobagh in Allahabad. A capacity crowd of 10,000 had gathered to witness the spectacular event. But due to insufficient filling or poor quality of the gas, the balloon failed to take off, even when all the ballasts were completely removed from the basket. As a true professional, he decided not to dishearten the crowd.
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HSL should become more cost effective in the near future. A version that can withstand windstorms could begin to replace conventional commercial fluorescent lighting systems with improved implementations in 2008 and beyond. The U.S. 2007 Energy Bill provides funding for HSL R&D;, and multiple large commercial buildings are ready to fund further HSL application development and deployment. At night, ORNL HSL uses variable-intensity fluorescent lighting electronic control ballasts.
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The utility of PCBs is based largely on their chemical stability, including low flammability and high dielectric constant. In an electric arc, PCBs generate incombustible gases. Use of PCBs is commonly divided into closed and open applications. Examples of closed applications include coolants and insulating fluids (transformer oil) for transformers and capacitors, such as those used in old fluorescent light ballasts, hydraulic fluids, lubricating and cutting oils, and the like.
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HMI bulbs (like all arc bulbs) need a current limiting unit to function. Two ways of doing this are described in the ballast section below. The problem of flickering exists only when using the bulb in combination with magnetic ballast (electronic ballasts produce flicker-free light). HMI bulbs (running with magnetic ballast) present an inherent problem of possibly producing light on film or video with a noticeable flicker.
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Guttridge, 2005, pp. 217–219. Before Decatur assumed command of Chesapeake he learned from observers, and then informed the Navy Secretary, that the British ships and were lightening their ballasts to prepare for a blockade at Norfolk.Guttridge, 2005, p. 101. During this segment of his life, Decatur's father, Stephen Decatur Sr., died in November 1808 at the relatively young age of 57, with his mother's death following the next year.
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Commercial buildings can greatly increase energy efficiency by thoughtful design, with today's building stock being very poor examples of the potential of systematic (not expensive) energy efficient design.Steffy, 1997 Commercial buildings often have professional management, allowing centralized control and coordination of energy conservation efforts. As a result, fluorescent lighting (about four times as efficient as incandescent) is the standard for most commercial space, although it may produce certain adverse health effects.Susan L. Burks, Managing your Migraine, Humana Press, New Jersey (1994) Cambridge Handbook of Psychology, Health and Medicine, edited by Andrew Baum, Robert West, John Weinman, Stanton Newman, Chris McManus, Cambridge University Press (1997) L. Pijnenburg, M. Camps and G. Jongmans-Liedekerken, Looking closer at assimilation lighting, Venlo, GGD, Noord-Limburg (1991)Igor Knez, "Effects of colour of light on nonvisual psychological processes", Journal of Environmental Psychology, Volume 21, Issue 2, June 2001, pages 201–208 Potential health concerns can be mitigated by using newer fixtures with electronic ballasts rather than older magnetic ballasts.
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Capacitors containing PCB were labelled as containing "Askarel" and several other trade names. PCB-filled capacitors are found in very old (pre 1975) fluorescent lamp ballasts, and other applications. High-voltage capacitors may catastrophically fail when subjected to voltages or currents beyond their rating, or as they reach their normal end of life. Dielectric or metal interconnection failures may create arcing that vaporizes dielectric fluid, resulting in case bulging, rupture, or even an explosion.
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Because of the power that would be lost, resistors are not used as ballasts for lamps of more than about two watts. Instead, a reactance is used. Losses in the ballast due to its resistance and losses in its magnetic core may be significant, on the order of 5 to 25% of the lamp input electric power. Practical lighting design calculations must allow for ballast loss in estimating the running cost of a lighting installation.
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The Energy Independence and Security Act of 2007 (Pub.L. 110-140) laid out the changes in legislation regarding lighting in the United States in Title III, Subtitle B. In this, the different bulbs being affected by the standards changes are first defined. Along with higher standards being created for bulbs, the ballasts are also required to increase efficiency. It is also outlined within EISA 2007 that there are lighting requirements within public buildings.
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In fact, the first British fluorescent lamps were designed to operate from 80-watt mercury vapor ballasts. There are also self-ballasted mercury vapor lamps available. These lamps use a tungsten filament in series with the arc tube both to act as a resistive ballast and add full spectrum light to that of the arc tube. Self-ballasted mercury vapor lamps can be screwed into a standard incandescent light socket supplied with the proper voltage.
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In a normal office building, lights usually consume about 44% of total energy. The New York Times Building uses less, because its design, lighting, and shading systems allow the sun to be the main source of light. Each of the more than 18,000 electrical ballasts in the lighting system contains a computer chip, allowing each room's lights to brighten or dim depending on whether a room is occupied and how bright the sun is.
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The Asian green mussel is found in the coastal waters of the Indo-Pacific region. However the mussels are introduced to other areas as an invasive species via boat hulls and water ballasts. The mussel inhabits estuarine habitats and is found in densities as high as 35,000 individuals per square meter on any submerged marine object. Although vivid green in appearance, the mussels are shrouded with overgrowth and are often hard to find.
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Because they have lower resistive losses than an inductive ballast, they are more energy efficient. However, high- frequency operation does not increase lamp efficiency as for fluorescent lamps. Pulse-start metal-halide bulbs don't contain a starting electrode which strikes the arc, and require an ignitor to generate a high-voltage (1–5 kV on cold strike, over 30 kV on hot restrike) pulse to start the arc. Electronic ballasts include the igniter circuit in one package.
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A modern ballast for powering a variety of T8 office lamps. An electrical ballast is a device placed in series with a load to limit the amount of current in an electrical circuit. A familiar and widely used example is the inductive ballast used in fluorescent lamps to limit the current through the tube, which would otherwise rise to a destructive level due to the negative differential resistance of the tube's voltage-current characteristic. Ballasts vary greatly in complexity.
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The complete compact fluorescent lamp (CFL) includes the Edison screwbase and plastic housing, the electronic ballast, and the fluorescent lamp which is formed into a spiral shape. Improvements in technology have allowed fluorescent lamps with color temperature and color rendition comparable to incandescent lighting. Compact fluorescent lamps are available in a variety of styles and shapes. Some have tubes and ballasts permanently connected, while others are separate allowing you to change the tube without changing the ballast.
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The average cost of these transformers is $200 to $250. While this makes the newer electronics cost about the same for the typical tanning bed, buckboost transformers are usually sold separately, so the total cost is not always obvious to the consumer at first glance. Schematic for Choke Ballasts: Note the use of one ballast per lamp, one lamp starter per lamp and a capacitor. Tanning beds may use 1 or several capacitors, depending on rating.
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Compact fluorescent lamp with GU24 cap A GU24 lamp fitting is a bi-pin connector for compact fluorescent lamps (CFL) or LED lamps that uses a bayonet mount–like twist-lock bi-pin connector instead of the Edison screw fitting used on many CFLs, LED lamps and incandescent light bulbs. The design was initiated by the U.S. EPA and the Lighting Research Center in 2004, in order to facilitate the deployment of compact fluorescent light bulbs with replaceable ballasts.
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An electronic ballast uses solid state electronic circuitry to provide the proper starting and operating electrical conditions to power discharge lamps. An electronic ballast can be smaller and lighter than a comparably-rated magnetic one. An electronic ballast is usually quieter than a magnetic one, which produces a line- frequency hum by vibration of the transformer laminations. Electronic ballasts are often based on switched-mode power supply (SMPS) topology, first rectifying the input power and then chopping it at a high frequency.
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Model of a ship fitted with ship camels A Ship camel is an external flotation tank that can be fitted to a ship to increase her buoyancy or reduce her draught. Its inner walls are concave and curve as to espouse the lines of the hull of the ship. The ship camel is partially sunk using ballasts, installed on ship, and water is then pumped out. The increased volume provided by the camels allow the system to float in a reduced draught.
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Fluorescent light fixtures cannot be connected to dimmer switches intended for incandescent lamps. Two effects are responsible for this: the waveform of the voltage emitted by a standard phase-control dimmer interacts badly with many ballasts, and it becomes difficult to sustain an arc in the fluorescent tube at low power levels. Dimming installations require a compatible dimming ballast. Some models of compact fluorescent lamps can be dimmed; in the United States, such lamps are identified as complying with UL standard 1993.
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When the primary current exceeds a certain value, the core is pushed into its saturation region, limiting further increases in secondary current. In a more sophisticated application, saturable core inductors and magnetic amplifiers use a DC current through a separate winding to control an inductor's impedance. Varying the current in the control winding moves the operating point up and down on the saturation curve, controlling the alternating current through the inductor. These are used in variable fluorescent light ballasts, and power control systems.
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In addition to physical fitness equipment, the company manufactured ballasts and counterweights for farms, industry and trucking. James founded DP in his basement and, over the next 15 years, the company ultimately grew to employ 1,500 people with plants in Opelika, AL; Los Angeles, and Toronto, with sales of about $1 billion annually. James served as the CEO of DP until 1977, when it was bought by the Liggett Group. James's son Gregory died of cystic fibrosis at the age of eight.
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The brown mussel is native to the tropical and sub-tropical regions of the Atlantic Ocean and Western Indian Ocean . It is found in waters off the west coast of Africa and the coast of South America up to the Caribbean, as well in the East Coast of Africa and Madagascar. It is accidentally introduced as an invasive species to the coast of Texas via the boat hulls and water ballasts of ships from Venezuela. Its distribution include: Chile, Peru, South Africa.
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3-way lamps and dimmable models with standard bases are available. Non-integrated CFLs have the ballast permanently installed in the luminaire, and usually only the fluorescent tube is changed at its end of life. Since the ballasts are placed in the light fixture, they are larger and last longer compared to the integrated ones, and they don't need to be replaced when the tube reaches its end-of-life. Non- integrated CFL housings can be both more expensive and sophisticated.
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They have two types of tubes: a bi-pin tube designed for conventional ballast, e.g. with G23 or G24d plug-in base, and a quad-pin tube designed for an electronic ballast or a conventional ballast with an external starter. A bi-pin tube contains an integrated starter, which obviates the need for external heating pins but causes incompatibility with electronic ballasts. Non-integrated CFLs can also be installed to a conventional light fixture using an adapter containing a built-in magnetic ballast.
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Aeros has developed a technology to avoid the need for ballast, which they call "control of static heaviness (COSH)". The main gas bag is inflated with helium to create lift for takeoff, then on landing some of the gas is re-compressed into a storage tank to partially deflate the gas bag and reduce lift. Worldwide Aeros was awarded a patent for this system in May 2015. It internally ballasts the non-flammable helium into the aircraft’s helium pressure envelopes (HPEs), helping the vehicle manage buoyancy.
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Fluorescent lamp with an electronic ballast. Electronic ballast for fluorescent lamp, 2×58 W Electronic ballast basic schematic Electronic ballasts and different compact fluorescent lamps Electronic starters use a different method to preheat the cathodes. They may be plug-in interchangeable with glow starters. They use a semiconductor switch and "soft start" the lamp by preheating the cathodes before applying a starting pulse which strikes the lamp first time without flickering; this dislodges a minimal amount of material from the cathodes during starting, giving longer lamp life.
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A 600W HPS produces 7% more light (lumen-per-watt) than a 1000W HPS. Although all HID lamps work on the same principle, the different types of bulbs have different starting and voltage requirements, as well as different operating characteristics and physical shape. Because of this a bulb won't work properly without a matching ballast, even if the bulb will physically screw in. In addition to producing lower levels of light, mismatched bulbs and ballasts will stop working early, or may even burn out immediately.
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Dan Flavin used electric fluorescent lights and ballasts to create sculpture. In the 1970s Frank Stella introduced honeycombed aluminum and glitter. In the 1980s Julian Schnabel made "plate paintings" with broken crockery stuck to the surface and then painted over, Anselm Kiefer and Richard Long used mud, soil or tar in their works. In the 1960s and again in the 1990s artists used excrement notably - the Italian artist Piero Manzoni in 1961 and the British artist Chris Ofili who specialized in using elephant dung in the 1990s.
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Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent electrical insulating properties. It is used in oil-filled transformers, some types of high-voltage capacitors, fluorescent lamp ballasts, and some types of high-voltage switches and circuit breakers. Its functions are to insulate, suppress corona discharge and arcing, and to serve as a coolant. Transformer oil is most often based on mineral oil, but alternative formulations with better engineering or environmental properties are growing in popularity.
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However, lighting controllers and ballasts are responsible for generating high levels of harmonic distortion, which can be filtered with some types of voltage optimiser, in addition reducing the need for lighting controllers. A common concern is that some lighting will fail to strike at lower voltages. However, this should not occur since the aim of voltage optimisation is not simply to reduce the voltage as far as possible, but to bring it to the service level voltage at which it was designed to operate most efficiently.
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A number of street light control systems have been developed to control and reduce energy consumption of a town's public lighting system. These range from controlling a circuit of street lights and/or individual lights with specific ballasts and network operating protocols. These may include sending and receiving instructions via separate data networks, at high frequency over the top of the low voltage supply or wireless. Street light controllers are smarter versions of the mechanical or electronic timers previously used for street light ON-OFF operation.
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A small draft allows pleasure boats to navigate through shallower water. This makes it possible for these boats to access smaller ports, to travel along rivers and even to 'beach' the boat. A large draft ensures a good level of stability in strong wind, as the center of gravity is lower (ballast over the keel of the boat). For example: Ballasts placed very low in the keel of a boat such as a dragon boat with a draft of 1.20 m for a length of 8.90 m.
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The incoming AC current is first rectified to DC, then converted to high frequency AC by the transistors, connected as a resonant series DC to AC inverter. The resulting high frequency is applied to the lamp tube. Since the resonant converter tends to stabilize lamp current (and light produced) over a range of input voltages, standard CFLs do not respond well in dimming applications and will experience a shorter lifespan and sometimes catastrophic failure. Special electronic ballasts (integrated or separate) are required for dimming service.
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The mixture of the metals used defines the color of the lamp. Some types, for festive or theatrical effect, use almost pure iodides of thallium, for green lamps, and indium, for blue lamps. An alkali metal, (sodium or potassium), is almost always added to reduce the arc impedance, allowing the arc tube to be made sufficiently long and simple electrical ballasts to be used. A noble gas, usually argon, is cold filled into the arc tube at a pressure of about 2 kPa to facilitate starting of the discharge.
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20 Nov. 2014.\--$10 billion per year) and the implementation of high-frequency ballasts ($5 billion per year), low-e windows (estimated $5-$10 billion per year), and more efficient refrigerators ($17 billion per year). Beyond saving energy and money, Rosenfeld's actions at California's Energy Commission have also helped paint California as an example to the United States in carbon dioxide emissions, setting California's per capita emissions to half the national average in 2000. Beyond setting standards and implementing programs, Rosenfeld and the California Energy Commission have invested money into research and development.
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Senate Measure Calls for a New Avenue - The Washington Times - April 11, 1911 - page 6 By May of the same year, the ballasts, ties and rails had been removed from Florida Avenue NE to Mount Olivet Street NE and the ties and rails were gone from Mount Olivet Street NE on-wards going North. While it was only a muddy path with no pavement, it was used by wagons to connect the communities north to the city and it was a straight line looking straight at the Capitol Building.
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The Falcon 9 carried a small number of nanosatellites to orbit as well. Included were the first U.S. Army nanosatellite, Space and Missile Defense Command — Operational Nanosatellite Effect, or SMDC-ONE, for a 30-day mission, and two 3U buses, the CubeSat Experiment (QbX), provided by the U.S. National Reconnaissance Office, also expected to remain in orbit for only 30 days. One of the weight ballasts inside the Dragon spacecraft was a metal barrel containing a wheel of French Le Brouère cheese. This cheese is produced in Bulgnéville, Vosges.
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It is the most recent expansion of the Caloocan-FTI line beyond Caloocan, and the first time in 2 decades that there has been rail activity. In September 2018, PNR engineers commenced the exploration of the site of the old Acacia railway station, and drafted plans to rebuild the dismantled rail lines there and set a target to reopen the service and station before the end of 2018. A ceremony was held to officially mark the commencement of the restoration of services. Soon after, railroad tracks were laid down along with ballasts.
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These innovations weren't just for the novelty but would eventually become the norm many different industries especially in the collier trade. The elaborate water ballast had virtually replaced the sand-and-gravel ballasts that were the industry standard previously. In 1848, Coutts took William Parkinson as a partner and started a new trading company called Coutts and Parkinson; they had a shipyard at Willington Quay. In 1852, their yard built the 900 ton W. S. Lindsay, the largest iron ship that had been built to date for the eponymous merchant William Schaw Lindsay.
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Some lamps produce ultraviolet radiation which is converted to visible light by a fluorescent coating on the inside of the lamp's glass surface. The fluorescent lamp is perhaps the best known gas- discharge lamp. Compared to incandescent lamps, gas-discharge lamps offer higher efficiency, but are more complicated to manufacture and most exhibit negative resistance, causing the resistance in the plasma to decrease as the current flow increases. Therefore, they usually require auxiliary electronic equipment such as ballasts to control current flow through the gas, preventing current runaway (arc flash).
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The route was to require extensive re-construction, including track doubling in several sections, thus raising costs significantly. Further studies showed that the entire railway required replacement of rails, sleepers, and ballasts in addition to reducing at-grade crossings. Planners also recommended the upgrade of the entire railway in one major project, rather than a phased project. The opposition parties in Rheinland-Pfalz criticized the plan, stating that travel times along the railway would be lengthier than current road travel times between Hahn and the Rhine-Main metropolitan area.
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The A set is the first passenger train in the world to use LED lamps for all lighting (except headlights). In doing so, the designers managed to remove almost 800 kg in reflectors and ballasts associated with fluorescent units, as well as reducing power consumption to around a quarter of that used by fluorescents. Woollen moquette fabric, a durable, vandal-resistant material, is used to cover the train's seats. The seats use specially developed shock absorbers such that the reversing feature is damped - this was a safety feature added to allow reversible seats which would contain passengers in the event of an accident.
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Metal halide lamps are widely used in the horticultural industry and are well-suited to supporting plants in earlier developmental stages by promoting stronger roots, better resistance against disease and more compact growth. The blue spectrum of light encourages compact, leafy growth and may be better suited to growing vegetative plants with much foliage. A metal halide bulb produces 60-125 lumens/watt, depending on the wattage of the bulb. They are now being made for digital ballasts in a pulse start version, which have higher electrical efficiency (up to 110 lumens per watt) and faster warmup.
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In 2016, Japanese biologists Konami Ando and Shin‐ichi Fujiwara performed a statistical test of ribcage strength among terrestrial, semi-aquatic, and fully aquatic mammals, and found that Ambulocetus clustered with fully aquatic mammals, because they assigned a very high rib density on par with fully aquatic sirenians which use their heavy, osteosclerotic ribs as ballasts. They then concluded Ambulocetus could not walk on land, but that the study was limited by a lack of information on the exact density of the bone, the location of the centre of mass, and the reliance of false ribs for thoracic support.
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She had discharged the last troops by 09:45 hours on 4 August 1919. Virginian then began her conversion back into a cargo ship and other preparations for demobilization. After the last troops had disembarked, shipyard workmen and the ship's crew bent to the task of taking down troop fittings, performing routine maintenance tasks, discharging ballasts, cleaning holds, and inventorying equipment. At 16:00 hours on 19 August 1919, she was decommissioned and formally turned over to a representative of the American- Hawaiian Steamship Company, Captain John S. Greene, who as Lieutenant Commander Green had served as USS Virginians first commanding officer.
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When lighting loads are in use for a high proportion of the time, energy savings on lighting equipment are extremely valuable. When voltage is reduced, incandescent lighting will see a large decrease in power drawn, a large decrease in light output and an increase in lifetime, as the previous extracts from the Electricians Guide illustrate. Since the decrease in light output will exceed the decrease in power drawn, the energy efficiency - luminous efficacy - of the lighting will drop. However, other types of lighting can also benefit from improved power quality, including systems with resistive or reactive ballasts.
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An HMI head on a stand Hydrargyrum medium-arc iodide (HMI) is the trademark name of Osram's brand of metal-halide gas discharge medium arc-length lamp, made specifically for film and entertainment applications. Hydrargyrum comes from the Greek name for the element mercury. An HMI lamp uses mercury vapour mixed with metal halides in a quartz-glass envelope, with two tungsten electrodes of medium arc separation. Unlike traditional lighting units using incandescent light bulbs, HMIs need electrical ballasts, which are separated from the head via a header cable, to limit current and supply the proper voltage.
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Some of the building materials, such as stone for the columns, timber as well as tiles were recycled from ballasts in ships. The local Indian community of Chulia Street also helped build the temple, and a statue of a man who appears to be an Indian holding a beam up at the ceiling was placed in the right wing as a reminder and gesture for their contribution. The temple was completed in 1842 at a cost of 30,000 Spanish dollars. In 1840, the clan association Hokkien Huay Kuan serving the Hokkien community was formed within the temple ground of Thian Hock Keng.
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Digital Serial Interface (DSI) is a protocol for the controlling of lighting in buildings (initially electrical ballasts). It was created in 1991 by Austrian company Tridonic and is based on Manchester-coded 8-bit protocol, data rate of 1200 baud, 1 start bit, 8 data bits (dimming value), 4 stop bits, and is the basis of the more sophisticated protocol Digital Addressable Lighting Interface (DALI). The technology uses a single byte to communicate the lighting level (0-255 or 0x00-0xFF). DSI was the first use of digital communication in lighting control, and was the precursor to DALI.
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Electronic ballast for 35 W metal halide light bulbs The electric arc in metal-halide lamps, as in all gas discharge lamps has a negative resistance property; meaning that as the current through the bulb increases, the voltage across it decreases. If the bulb is powered from a constant voltage source such as directly from the AC wiring, the current will increase until the bulb destroys itself; therefore, halide bulbs require electrical ballasts to limit the arc's current. There are two types: #Inductive ballast - Many fixtures use an inductive ballast, also known as a magnetic ballast, similar to those used with fluorescent lamps. This consists of an iron-core inductor.
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In Europe, and most 220-240 V territories, the line voltage is sufficient to start lamps over 20W with a series inductor. In North America and Japan however, the line voltage (120 V or 100 V respectively) may not be sufficient to start lamps over 20 W with a series inductor, so an autotransformer winding is included in the ballast to step up the voltage. The autotransformer is designed with enough leakage inductance (short-circuit inductance) so that the current is appropriately limited. Because of the large inductors and capacitors that must be used, reactive ballasts operated at line frequency tend to be large and heavy.
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The management explained that the gasoline was brought in to fuel their bumper boats, and that the tenant's action was a standard procedure as cotton was used as stuffing for the plush toys offered as prizes in some of the games. It also denied the alleged criminal motive of the employees, explaining that the business was lucrative especially during the Christmas season. Despite its protests, however, the management has vowed to cooperate in the probe. On December 27, 2019, the BFP spokesperson identified the cause as electrical fire due to overheating of one of the light ballasts from a game booth located at Star City's ground floor.
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All the major features of fluorescent lighting were in place at the end of the 1920s. Decades of invention and development had provided the key components of fluorescent lamps: economically manufactured glass tubing, inert gases for filling the tubes, electrical ballasts, long-lasting electrodes, mercury vapor as a source of luminescence, effective means of producing a reliable electrical discharge, and fluorescent coatings that could be energized by ultraviolet light. At this point, intensive development was more important than basic research. In 1934, Arthur Compton, a renowned physicist and GE consultant, reported to the GE lamp department on successful experiments with fluorescent lighting at General Electric Co., Ltd.
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Rapid start ballast designs provide windings within the ballast that continuously warm the cathode filaments. Usually operating at a lower arc voltage than the instant start design; no inductive voltage spike is produced for starting, so the lamps must be mounted near a grounded (earthed) reflector to allow the glow discharge to propagate through the tube and initiate the arc discharge. In some lamps a grounded "starting aid" strip is attached to the outside of the lamp glass. This ballast type is incompatible with the European energy saver T8 fluorescent lamps because these lamps requires a higher starting voltage than that of the open circuit voltage of rapid start ballasts.
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Most go by the deluxe (DX) designation on the lamp and have a white appearance to the bulb. Mercury Vapor Bulbs come in either clear or coated with powers of 50, 75, 100, 175, 250, 400, 700 or 1,000 Watts. The Mercury Vapor lamp is considered obsolete by today's standards and many places are taking them out of service. As of 2008, the sale of new mercury vapor streetlights and ballasts was banned in the US by the Energy Policy Act of 2005, although the sale of new bulbs for existing fixtures does continue, but the bulbs were also banned in 2015 in Europe.
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Since the IGBTs switch on and off at a regulated cycle rate, a generator can be slightly off-speed and the lamp will still be flicker-free, which is not the case with a standard magnetic ballast. The square wave nature of the output results in a straight-line power output from the lamp. The time where cathodes aren't emitting electrons of high enough energy is very short, meaning that safe (flicker-free) filming can occur at camera framerates up to 10,000 frame/s on most electronic ballasts. Unfortunately, this very sharp switching on and off inherent to the square- waveform causes extremely high frequency vibrations in the lamp.
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Serpentines find use in industry for a number of purposes, such as railway ballasts, building materials, and the asbestiform types find use as thermal and electrical insulation (chrysotile asbestos). The asbestos content can be released to the air when serpentine is excavated and if it is used as a road surface, forming a long-term health hazard by breathing. Asbestos from serpentine can also appear at low levels in water supplies through normal weathering processes, but there is as yet no identified health hazard associated with use or ingestion. In its natural state, some forms of serpentine react with carbon dioxide and re-release oxygen into the atmosphere.
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An instant start ballast does not preheat the electrodes, instead using a relatively high voltage (~600 V) to initiate the discharge arc. It is the most energy efficient type, but yields the fewest lamp-start cycles, as material is blasted from the surface of the cold electrodes each time the lamp is turned on. Instant-start ballasts are best suited to applications with long duty cycles, where the lamps are not frequently turned on and off. Although these were mostly used in countries with 100-120 volt mains supplies (for lamps of 40 W or above), they were briefly popular in other countries because the lamp started without the flicker of switch start systems.
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PRS's Dragon humbucker Single-coil pickups act like a directional antenna and are prone to pick up mains hum — nuisance alternating current electromagnetic interference from electrical power cables, power transformers, fluorescent light ballasts, video monitors or televisions — along with the musical signal. Mains hum consists of a fundamental signal at a nominal 50 or 60 Hz, depending on local current frequency, and usually some harmonic content. To overcome this, the humbucking pickup was invented by Joseph Raymond "Ray" Butts (for Gretsch), while Seth Lover also worked on one for Gibson.Wheeler. p.214 Who developed it first is a matter of some debate, but Butts was awarded the first patent () and Lover came next ().
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Waveform distortion can be mathematically analysed to show that it is equivalent to superimposing additional frequency components onto a pure sinewave. These frequencies are harmonics (integer multiples) of the fundamental frequency, and can sometimes propagate outwards from nonlinear loads, causing problems elsewhere on the power system. The classic example of a non-linear load is a rectifier with a capacitor input filter, where the rectifier diode only allows current to pass to the load during the time that the applied voltage exceeds the voltage stored in the capacitor, which might be a relatively small portion of the incoming voltage cycle. Other examples of nonlinear loads are battery chargers, electronic ballasts, variable frequency drives, and switching mode power supplies.
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Larger ships try to maintain an average water draft when they are light (without cargo) in order to make a better sea crossing and reduce the effects of the wind (high center of velic force). In order to achieve this they use sailing ballasts to stabilize the ship, following the unloading of cargo. The water draft of a large ship has little direct link with its stability because stability depends solely on the respective positions of the metacenter of the hull and the center of gravity. It is also true, however, that a "light" ship has quite high stability which can lead to implying too much rolling of the ship (due to memory).
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Different ballasts for fluorescent and discharge lamps Fluorescent lamps are negative differential resistance devices, so as more current flows through them, the electrical resistance of the fluorescent lamp drops, allowing for even more current to flow. Connected directly to a constant-voltage power supply, a fluorescent lamp would rapidly self-destruct because of the uncontrolled current flow. To prevent this, fluorescent lamps must use a ballast to regulate the current flow through the lamp. The terminal voltage across an operating lamp varies depending on the arc current, tube diameter, temperature, and fill gas. A general lighting service T12T12 specifies the bulb's diameter in 1/8 inch units; a T12 bulb is 12×(1/8) inches or in diameter. lamp operates at 430 mA, with 100 volts drop.
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Fluorescent lamps with magnetic ballasts flicker at a normally unnoticeable frequency of 100 or 120 Hz and this flickering can cause problems for some individuals with light sensitivity; they are listed as problematic for some individuals with autism, epilepsy, lupus, chronic fatigue syndrome, Lyme disease, and vertigo. The "beat effect" problem created when shooting photos under standard fluorescent lighting A stroboscopic effect can be noticed, where something spinning at just the right speed may appear stationary if illuminated solely by a single fluorescent lamp. This effect is eliminated by paired lamps operating on a lead-lag ballast. Unlike a true strobe lamp, the light level drops in appreciable time and so substantial "blurring" of the moving part would be evident.
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Xetec was the first to offer the popular Fish disks collection on CD-ROM with their three-volume set of Fish & More discs. Xetec also developed a few products for Macintosh and PC computers, products for the RC hobby market, and spent a number of years in research and development of solid-state fluorescent lighting ballasts, for which Jon Flickinger holds two patents. In summary, Xetec's total list of products include these: Lt. Kernal, Serial Printer Interface, Graphics Printer Interface, Super Graphix, Super Graphix Jr, Super Graphix Gold, Graphix AT, Fontmaster, Fontmaster II, Fontmaster 128, Printer Enhancer, FastTape, FastTrak, FastCard, FastCard Plus, MiniFastCard, FastRAM, Fish & More (vols. I, II, III), CDx CD-ROM Filesystem, CDx 650, Beeping Tomm, SuperWriter 924, SCAD.
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Where reactive loads are present, such as with capacitors or inductors, energy storage in the loads results in a phase difference between the current and voltage waveforms. During each cycle of the AC voltage, extra energy, in addition to any energy consumed in the load, is temporarily stored in the load in electric or magnetic fields then returned to the power grid a fraction of the period later. Electrical circuits containing predominantly resistive loads (incandescent lamps, heating elements) have a power factor of almost 1, but circuits containing inductive or capacitive loads (electric motors, solenoid valves, transformers, fluorescent lamp ballasts, and others) can have a power factor well below 1. In the electric power grid, reactive loads cause a continuous "ebb and flow" of nonproductive power.
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The neuralia and pleuralia–the bony portions of the carapace–are particularly thin, and the ribs, especially the first rib, and the shoulder girdle are unusually heavy and may have had to carry extra stress to compensate, a condition seen in ancient ancestral turtles. Archelon has osteosclerotic structures, where the bone is dense and heavy, which probably served as ballasts in life similar to the limb bones of whales and other open-ocean animals. The carapace, in life, probably featured a row of ridges along the midline over the chest region, perhaps totaling in seven ridges, with each ridge peaking at either . In the absence of firmly jointed neck and pleural plates, the skin over the carapace was probably thick, strong, and leathery in order to compensate and properly support the shoulder girdle.
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The system can be seen as a type of transformer, with the power coupler (inductor) forming the primary coil and the gas discharge arc in the bulb forming the one-turn secondary coil and the load of the transformer. The ballast is connected to mains electricity, and is generally designed to operate on voltages between 100 and 277 VAC at a frequency of 50 or 60 Hz, or on a voltage between 100 and 400 VDC for battery fed emergency light systems. Many ballasts are available in low voltage models so can also be connected to DC voltage sources like batteries for emergency lighting purposes or for use with renewable energy (solar and wind) powered systems. In other conventional gas discharge lamps, the electrodes are the part with the shortest life, limiting lamp lifespan severely.
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For example a 0–200 A meter can be turned into a 0–20 A meter by winding the conductor 10 times around the jaw's core. Columbia iron vane type clamp-on ammeter, with heads for different ranges Less-expensive clamp meters use a rectifier circuit which actually reads mean current, but is calibrated to display the RMS current corresponding to the measured mean, giving a correct RMS reading only if the current is a sine wave. For other waveforms readings will be incorrect; when these simpler meters are used with non-sinusoidal loads such as the ballasts used with fluorescent lamps or high- intensity discharge lamps or most modern computer and electronic equipment, readings can be quite inaccurate. Meters which respond to true RMS rather than mean current are described as "true RMS".
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The lamp had a thermal starter built into the 4 pin base. The power requirements were much larger than using an inductive ballast (though the consumed current was the same), but the warmer light from the lamp type of ballast was often preferred by users particularly in a domestic environment. Resistive ballasts were the only type that was usable when the only supply available to power the fluorescent lamp was DC. Such fittings used the thermal type of starter (mostly because they had gone out of use long before the glow starter was invented), but it was possible to include a choke in the circuit whose sole purpose was to provide a pulse on opening of the starter switch to improve starting. DC fittings were complicated by the need to reverse the polarity of the supply to the tube each time it started.
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It was soon made obsolete by newer developments, and the technology lay more or less dormant for years. The inductive output tube has re-emerged within the last twenty years after having been discovered to possess particularly suitable characteristics (broadband linearity) for the transmission of digital television and high-definition digital television. In research undertaken prior to the transition from analog to digital television broadcasting, it was discovered that electromagnetic interference from lightning, high voltage AC power transmission, AC rectifiers, and ballasts used in fluorescent lighting, greatly affected low-band VHF channels (In North America, channels 2,3,4,5, & 6) making it difficult to impossible to use them for digital television. These low-numbered channels were often the first television broadcasters in a given city, and were often large, vital operations which had no choice but to relocate to UHF.
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IES Lighting Handbook 1984 Electronic ballast retrofits to existing street lights had been tested in some Canadian provinces circa 2012; since then LED retrofits have become more common. With the higher efficiency of the ballast itself and the higher lamp efficacy at higher frequency, electronic ballasts offer higher system efficacy for low pressure lamps like the fluorescent lamp. For HID lamps, there is no improvement of the lamp efficacy in using higher frequency, but for these lamps the ballast losses are lower at higher frequencies and also the light depreciation is lower, meaning the lamp produces more light over its entire lifespan. Some HID lamp types like the ceramic discharge metal halide lamp have reduced reliability when operated at high frequencies in the range of ; for these lamps a square wave low frequency current drive is mostly used with frequency in the range of , with the same advantage of lower light depreciation.
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As currently implemented the Energy Conservation Program affects over 50 appliances, including residential, commercial and industrial, lighting , and plumbing products. Regulated residential products are clothes dryers, clothes washers, central air conditioners and heat pumps, ceiling fans, battery chargers and external power supplies, dehumidifiers, heating equipment, dishwashers, kitchen ranges and ovens, microwaves, pool heaters, refrigerators and freezers, furnace fans, furnaces and boilers, room air conditioners, set-top boxes, televisions, and water heaters. Regulated commercial and industrial products include ice makers, clothes washer, air conditioners and heat pumps, pumps, refrigerated beverage vending machines, unit heaters, walk-in coolers and freezers, fans and lowers, warm air furnaces, boilers, refrigeration equipment, water heaters, computer room air conditioners, distribution transformers, electric motors, and compressors. Regulated lighting equipment include ceiling fan light kits, certain lamps, fluorescent lamp ballasts, fluorescent lamps, incandescent lamps, high- intensity discharge lamps, exit sign lamps, incandescent reflector lamps, LED lamps, luminaires, compact fluorescent lamps, metal halide lamp fixtures, torchieres, and traffic signals.
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Diagram images of types of Portuguese slave transport, similar to other slavers On April 27, 1794, the São José sailed from Lisbon, Portugal, captained by Manuel João Pereira. In its hold were a load of carefully calibrated iron ballasts that sailing ships required in order to effectively transport on the open ocean the shifting weight of hundreds of individual captive humans. The ship's destination, the Portuguese colony of Mozambique in southeastern Africa, was a relatively new source of slave labor for the Atlantic slave trade. The São José is one of the first known ships to attempt the long-distance voyage from Portugal to Mozambique to Brazil. The ship’s path represents European slave traders’ increased efforts to obtain slaves. More than two centuries of slave trade along Africa’s west coast reduced the population, and along with increasing competition, motivated Portugal to send ships 7,000 miles to one of the farthest, cheapest sources of slaves in the trans-Atlantic trade, Mozambique, Africa, and then ship the slaves around the Cape of Africa to Brazil.
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