Among all kinds of instruments, the transmitter is the most widely used and universal,and the transmitters are generally divided into pressure transmitters and differential pressure transmitters.Transmitters are commonly used to measure pressure, differential pressure, vacuum, level, flow and density. The transmitter has two-wire system and four-wire system,two-wire system transmitters more;There are intelligent and non-intelligent, intelligent transmitters gradually more; There are pneumatic and electric, electric transmitters in the majority;In addition, according to the application,there are intrinsic safety type (intrinsic safety type) and explosion-proof type; according to the application under working conditions,the main types of transmitters are as follows:
※ Low (micro) pressure / low (micro) differential pressure transmitter;
※ Medium pressure / medium differential pressure transmitter;
※ High pressure / high differential pressure transmitter;
※ Absolute pressure/vacuum/negative pressure differential pressure transmitter;
※ High temperature / pressure, differential pressure transmitter;
※ Corrosion resistant / pressure, differential pressure transmitter;
※ Easily crystallized / pressure, differential pressure transmitter.
Transmitter selection is usually based on installation conditions, environmental conditions, instrument performance, economy, and media.In practical applications,it can be divided into direct measurement and indirect measurement;which are used for process measurement, process control and device interlocking.Common transmitters include ordinary pressure transmitter, differential pressure transmitter, single flange transmitter, double flange transmitter,insertion type flange transmitter, etc.
Pressure transmitters and differential pressure transmitters measure pressures and differential pressures (the difference between the two pressures) by name alone,but there are many quantities that can be indirectly measured.For example, pressure transmitter can measure the liquid level in the device besides measuring the pressure.When measuring the liquid level in an atmospheric pressure vessel, a pressure transmitter is required. When measuring the liquid level of the pressurized vessel,two pressure/differential pressure transmitters can be considered, that is, one lower limit of measurement, one upper limit of measurement, and their output signals are subtracted, and the liquid level can be measured.In this case, differential pressure transmitters are generally used. It can also be used to measure the density of a medium if the liquid level and pressure in the vessel are constant.The measurement range of the pressure transmitter can be made very wide, starting from absolute pressure 0 to more than 100 MPa (general condition).
In addition to measuring the differential pressure of the two measured pressures, the differential pressure transmitter can also measure the flow of the medium fluids with various throttling elements, and can directly measure the liquid level of the pressurized vessel and the liquid level of the atmospheric pressure vessel and pressure and negative pressure.
The structure of the pressure/differential pressure transmitter is divided into a common type and an isolated type.The measuring diaphragm capsule of the ordinary pressure/differential pressure transmitter is one, which directly senses the pressure or differential pressure of the measured medium; The measuring diaphragm capsule of isolated type receives a pressure of a stabilizing liquid (generally silicone oil) which is sealed between the two diaphragms and the diaphragm directly receiving the measured pressure is an outer diaphragm. The diaphragm of the original common type diaphragm capsule is an inner diaphragm.When the pressure signal is received on the outer diaphragm, the pressure of the outer diaphragm is transmitted to the ordinary diaphragm capsule by the transmission of the silicone oil, so that the pressure felt by the outer diaphragm can be measured.
</a> France, which has been at the forefront of international diplomacy on Syria, firmly backs the rebels and has strategic and historic interests in the region. It urged military action after a chemical attack on Aug. 21 that Paris and Washington blame on Bashar Assad's government.
</a> He added, "You know how Prince had a lot of girls back in the day? Prince was, like, the guy. I'm just that, today. But most women won't have any complaints if they've been with me. They can't really complain. It's all good."
</a> "Contacts across Districts generally remained cautiouslyoptimistic in their outlook for future economic activity,although many also noted an increase in uncertainty due largelyto the federal government shutdown and debt ceiling debate," theFed said.
</a> Iran is traditionally OPEC's second-largest producer behindSaudi Arabia, but it was overtaken by Iraq in 2012 as Westernsanctions over Iran's nuclear programme curbed Iranian exports. (Reporting by Alex Lawler; Editing by Mark Potter)
</a> “But, there is no age limit for donation. The team has become very good at locating the best matches, for instance a 75-year-old male who donates a kidney will most likely go to another 75-year-old male.”
</a> With horizontal fins at the tip of each rudder and daggerboard blade below the water's surface, the radical yachts commissioned by Oracle Corp's Ellison, who could definethe parameters of this year's Cup boats because he won the 2010America's Cup in Valencia, Spain, can "hydrofoil" atop the wavesat speeds of more than 50 miles per hour.
</a> "Anticipating possible market moves specific to this event,CME will increase margin for all OTC IRS portfolios by applyingthe Event Risk margin add-on of 12 percent to the base margins,"CME said in a notice posted on its website, reffering toover-the-counter interest rate swaps.
</a> The Internet and social media in Kenya, which played a central role in this year's elections by allowing Kenyans to question candidates, took on a new function Tuesdayâspreading messages of peace to avert new bloodshed.
</a> Earlier, a disheveled Republican Senator Ted Cruz finished a21-hour, 19-minute marathon of standing and speaking on theSenate floor, arguing for defunding Obamacare as part of thegovernment-funding bill.
</a> Researchers from Britain's Oxford University and from the Swiss drug firm Roche used mice to analyze patterns of genes in an area of the brain called the suprachiasmatic nuclei (SCN) - which in mammals pulls every cell in the body into the same biological rhythm.
</a> But Poland is one of the European Union's least innovativemembers, something that has to change if Poland is ever to jointhe world's wealthier nations. Bienkowska said IT, medicine andaviation were among the most promising sectors.
</a> "Final details of when our sites will be back online will be communicated as soon as possible. We're currently doing everything in our power to ensure our sites and, more importantly, our users, are not affected by such issues in future.
</a> There are three cruising areas in the region: the Eastern Caribbean, typically including Puerto Rico, the Virgin Islands and, for Florida departures, the Bahamas; the western Caribbean, taking in the Cayman Islands, Jamaica and Mexico; and the Southern Caribbean, visiting southerly Windward Islands and the Dutch Antilles.
</a> Under pressure from UKIP and like-minded lawmakers in his own party, Cameron has promised to try to renegotiate Britain's EU ties and hold a referendum on its continued membership by the end of 2017 if he is re-elected.
</a> Details about the number of customers that are likely to be affected by this news is hard to come by, but the firm did sign a deal with tech giant IBM in 2011 to help underpin its SmartCloud technology.
</a> Among Palestinians there is widespread pessimism over Abbas' chances of persuading the right-wing government of Prime Minister Benjamin Netanyahu to abandon its settlement program and hand back land it captured in the 1967 Middle East war.
</a> Along with Perry Corp, hedge fund managers Kyle Bass ofHayman Capital Management and Larry Robbins of Glenview CapitalManagement have taken sizeable stakes in Penney of 5.2 percentand 9.1 percent, respectively.
</a> The former resort community is located about 50 miles west of Knoxville. It had controlled access with a gate until 2010, when new owners got rid of it. That move gave rise among some residents about security in the 3,000-acre community
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</a> The new laptop’s display measures 11.6 inches diagonally, the same as a popular Chromebook model from Samsung Electronics Co. The Chromebook 11 weighs slightly less, at 2.3 pounds, compared with 2.4 pounds for the Samsung model.
</a> Then at 1.04 energy returns for the words “Make straight the way of the Lord”. Even more subtle is the freezing of the harmonic motion at 2.06, for John the Baptist’s awe-inspiring announcement, “There stands one among you, whom you know not”, meaning Christ; the shift to a new harmony at 2.11 encapsulates the mystery of that revelation.
</a> But Obama also took a stab at Putin, saying, "I know the press likes to focus on body language, and he's got that kind of slouch, looking like the bored kid in the back of the classroom. But the truth is, is that when we're in conversations together, oftentimes it's very productive."
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</a> Green smoothies are sweet, creamy and full of fruit â perfect for kids, Rinaldi says. She suggests opting for recipes with fewer greens, and then adding more as children become accustomed to the flavors. A âmint cookies ân creamâ smoothie, for example, includes macadamia nuts, raw cacao powder, pitted dates and fresh mint leaves, among other ingredients.
</a> At the main sit-in, vendors said they have sold hundreds of gas masks, goggles and gloves to protesters readying for police tear gas. Three waist-high barriers of concrete and wood have been built against armored vehicles.
</a> Hagel has had a more hands-on approach than Panetta and had wanted Carter's role more strictly defined with a primary focus on the defense budget instead of broader policy issues, according to some former officials and a recent report in Foreign Policy.
</a> In the southeastern city of Xiamen, more than 16 billionyuan were earmarked for 10 projects that include construction ofa 100,000-tonne luxury liner, a cruise terminal and a shippingbusiness centre, the official Xinhua news agency has reported.
</a> He hit Gordon for 11 yards on a slant. Fullback Chris Ogbonnaya made a Vikings defender miss and picked up 11 after a short pass. Hoyer hit Cameron on a cross for 14 yards and Gordon on an in for 12 yards to the 7.
</a> Wright and Simon Pegg, his co-writer and regular leading man, are now either side of 40, and so are their characters: five former friends who convene in their old home town, Newton Haven, for a pub crawl that will end all pub crawls, and perhaps more than that.
</a> BEIJING/HONG KONG - China reiterated its opposition on Thursday to a European Union plan to limit airline carbon dioxide emissions and called for talks to resolve the issue a day after its major airlines refused to pay any carbon costs under the new law.
</a> A second suspect was arrested before dawn Saturday and confessed to authorities about his involvement in the incident, Singh told reporters. Members of India's elite crime unit were hunting three more suspects.
</a> With her husband, Israel, Gil organized a volunteer outreach program, going into the storm-ripped neighborhoods of Staten Island. âWe showed up in buildings that looked unlivable and found people inside cold and hungry,â she said.
</a> It would be Rossâ first start as a Giant since the team won Super Bowl XLVI; he spent last season with the Jaguars. His assignment will be significantly different from last week, but his mind-set wonât be.
</a> And endosulfan - a substance so nasty the United Nations wants it eliminated worldwide - was banned only by a Supreme Court order in 2011. The decision came a few months after the chief minister of the southern state of Kerala, the top elected official, went on a day-long hunger fast to demand the ban.
</a> New Jersey broke a 1-1 tie at 16:03 of the second period when Zubrus beat MacDonald from just inside the blue-line with a slap shot. Giordano fed a pass across to Wideman on Calgaryâs third power play and he one-timed a slap shot inside the goal post while Curtis Glencross screened Brodeur. New Jersey struck first at 13:58 of the first, shortly after a power play expired.
</a> Sales at the optical products business, its other major division, also fell about 1.5 percent to $182.3 million. JDS Uniphase's optical communications products are used by network equipment makers such as Cisco Systems Inc.
</a> Fisheries Minister Richard Benyon said the court had "vindicated" his decision to reallocate underused quota, and said "putting fishermen at the heart of the decision is good news".
</a> âThe fire that he comes in with every day, he loves this game, he loves everything about it,â Snee says. âHe loves the preparation. He loves watching teams come together and jell. He just loves being around this game.
</a> It is also a tough slog to get to the top of the profession. Referees start their training at level nine and have to be gradually promoted until they reach the highest level, and with it the chance to referee in the Football League. Climbing up the ladder takes years of dedication and persistence – not to mention an extreme level of fitness.
</a> WalesOnline is part of Media Wales, publisher of the Western Mail, South Wales Echo, Wales on Sunday and the seven Celtic weekly titles, offering you unique access to our audience across Wales online and in print.
</a> Investors contended that between August 2006 and June 2009,a period covering the global financial crisis and a plunge instock prices, ProShares failed to disclose the risks that itsETFs might post substantial losses, and knew it could happeneven if investors bet correctly on a market's direction.
</a> Tepco has already removed two unused fuel assemblies from the pool in a test operation last year, but these rods are less dangerous than the spent bundles. Extracting spent fuel is a normal part of operations at a nuclear plant, but safely plucking them from a badly damaged reactor is unprecedented.
</a> In 1981, in Winter Park near Orlando, a sinkhole measuring 320 feet wide and 90 feet deep swallowed a two-story house, part of a Porsche dealership and an Olympic-size swimming pool. The site is now an artificial lake.
</a> Army cut it to 8-7. Eastern Michigan needed just three plays and 53 seconds to score again, however. On the second play of the drive, Hill broke through traffic and ran right for a 43-yard gain to Armyâs 12.
</a> The deal, worth over eight-and-a-quarter billion euros, was announced in February and immediately attracted flak, but after ceding landing and takeoff slots in London and Philadelphia the EU granted approval.
</a> The Emmy's are about ratings, and TV is all about attracting younger viewers. Hardly anyone watching has heard of any of these people except for Gandolfini and Monteith. It's about 'relevance' not respect or whether Monteith has earned his place in the list of special mentions.
</a> Besides, we really like all the good guys. The way they plot out their improbable victory stands in the finest tradition of comic superheroes, where individual skills mesh together to form an even greater whole.
</a> A rare, northern right whale was rescued from an entanglement of fishing line off the coast of Virginia Beach after a pair of men on a chartered boat spotted the floundering cetacean and decided to help.
</a> Let me be clear: I am not saying leave politics to your elders and betters. Obviously, citizens of the countries involved have a right and obligation to form opinions and take positions on these things. What they probably ought not to do is take risks for themselves and create fee income for financial services firms by putting those opinions into investment practice.
</a> âWhen I first came up I was just trying to do too much," Wheeler explained. " âOh I got to hit the outside corner to this guyâ or âI got to throw hard in to this guy,â when you just have to throw it inside and let your ball run and do its own thing.