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52-461: The promontory of Sagres has always been important for sailors because it offers a shelter for ships before attempting the dangerous voyage around Cape St. Vincent (could be Belixe Bay, between Sagres Point and the Cape, or Sagres Bay, to the east). Given the dangers of being blown onto the coastal rocks, captains preferred to wait in the lee of the point until favourable winds allowed them to continue. There

104-471: A "fourth big scientific revolution" after World War II is the development of scientific instrumentation, not only in chemistry but across the sciences. In chemistry, the introduction of new instrumentation in the 1940s was "nothing less than a scientific and technological revolution" in which classical wet-and-dry methods of structural organic chemistry were discarded, and new areas of research opened up. As early as 1954, W. A. Wildhack discussed both

156-505: A central control focus, this arrangement was inflexible as each control loop had its own controller hardware, and continual operator movement within the control room was required to view different parts of the process. With coming of electronic processors and graphic displays it became possible to replace these discrete controllers with computer-based algorithms, hosted on a network of input/output racks with their own control processors. These could be distributed around plant, and communicate with

208-482: A certain local custom, and are changed in position by such as turn them incorrectly. It is not lawful to offer sacrifice there, nor yet to approach the place during the night, for it is said that then the gods take up their abode at the place. Those who go thither to view it stay at a neighbouring village overnight, and proceed to the place on the morrow, carrying water with them, as there is none to be procured there. No part of Cape St. Vincent fits this description, but on

260-501: A collection of equipment might be used to automate the testing of drinking water for pollutants. Instrumentation engineering is the engineering specialization focused on the principle and operation of measuring instruments that are used in design and configuration of automated systems in areas such as electrical and pneumatic domains, and the control of quantities being measured. They typically work for industries with automated processes, such as chemical or manufacturing plants, with

312-449: A desired output variable, and provide either remote monitoring or automated control capabilities. Each instrument company introduced their own standard instrumentation signal, causing confusion until the 4–20 mA range was used as the standard electronic instrument signal for transmitters and valves. This signal was eventually standardized as ANSI/ISA S50, "Compatibility of Analog Signals for Electronic Industrial Process Instruments", in

364-532: A destination. Automotive instrumentation must be cheap and reliable over long periods in harsh environments. There may be independent airbag systems that contain sensors, logic and actuators. Anti-skid braking systems use sensors to control the brakes, while cruise control affects throttle position. A wide variety of services can be provided via communication links on the OnStar system. Autonomous cars (with exotic instrumentation) have been shown. Early aircraft had

416-575: A few sensors. "Steam gauges" converted air pressures into needle deflections that could be interpreted as altitude and airspeed. A magnetic compass provided a sense of direction. The displays to the pilot were as critical as the measurements. A modern aircraft has a far more sophisticated suite of sensors and displays, which are embedded into avionics systems. The aircraft may contain inertial navigation systems , global positioning systems , weather radar , autopilots, and aircraft stabilization systems. Redundant sensors are used for reliability. A subset of

468-451: A pressurized bellows displaces a pen. Integrating sensors, displays, recorders, and controls was uncommon until the industrial revolution, limited by both need and practicality. Early systems used direct process connections to local control panels for control and indication, which from the early 1930s saw the introduction of pneumatic transmitters and automatic 3-term (PID) controllers . The ranges of pneumatic transmitters were defined by

520-634: A set of tombstones present. Inside this unpretentious church, the 17th century Baroque retable above the altar originates from the Capela de Santa Catarina do Forte de Belixe (St. Catherine's Chapel in Belixe Fortress), while the polychrome statues of St. Vincent and St. Francis were once part of the Franciscan convent on the Cape St. Vincent. Next to the church stands a replica stone standard ( padrão ), used by

572-720: Is a collective term for measuring instruments , used for indicating, measuring, and recording physical quantities . It is also a field of study about the art and science about making measurement instruments, involving the related areas of metrology , automation , and control theory . The term has its origins in the art and science of scientific instrument-making . Instrumentation can refer to devices as simple as direct-reading thermometers , or as complex as multi- sensor components of industrial control systems . Instruments can be found in laboratories , refineries , factories and vehicles , as well as in everyday household use (e.g., smoke detectors and thermostats ). Instrumentation

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624-451: Is a device that produces an output signal, often in the form of a 4–20  mA electrical current signal, although many other options using voltage , frequency , pressure , or ethernet are possible. The transistor was commercialized by the mid-1950s. Instruments attached to a control system provided signals used to operate solenoids , valves , regulators , circuit breakers , relays and other devices. Such devices could control

676-537: Is a site of exuberant marine life and a high concentration of birds nesting on the cliffs, such as the rare Bonelli's eagle , peregrine falcons , kites , rock thrushes , rock pigeons , storks and herons . The present lighthouse is 24 metres (79 ft) high and was built over the ruins of a 16th-century Franciscan convent in 1846. The statues of St. Vincent and St. Francis Xavier had been moved to church of Nossa Senhora da Graça on Point Sagres 3 kilometres (1.9 mi) away. This lighthouse, guarding one of

728-449: Is based on sensed antenna direction and sensed time delay. The other information is embedded in the transponder transmission. Among the possible uses of the term is a collection of laboratory test equipment controlled by a computer through an IEEE-488 bus (also known as GPIB for General Purpose Instrument Bus or HPIB for Hewlitt Packard Instrument Bus). Laboratory equipment is available to measure many electrical and chemical quantities. Such

780-586: Is not known (it is popularly believed to have been destroyed by the 1755 Lisbon earthquake ). The 16th century bulwark-like fortress was severely damaged during the Great Earthquake of 1755. It was restored in the mid 20th century, but there is still a 16th-century turret present. After passing through the thick tunnel entrance, one sees a giant pebble compass rose ( rosa dos ventos ) of 43 m diameter. Normally compass roses are divided into 32 segments, but strangely this one has 40 segments (probably an error of

832-407: Is often knowledgeable of techniques to minimize temperature gradients that cause air turbulence within the telescope. Instrumentation technologists, technicians and mechanics specialize in troubleshooting, repairing and maintaining instruments and instrumentation systems. Ralph Müller (1940) stated, "That the history of physical science is largely the history of instruments and their intelligent use

884-458: Is some question whether Sagres Point, whose name derives from Sacrum Promontorium , or neighboring Cape St. Vincent , was the ancient sacred promontory. Strabo believed the promontory was the most westerly point of the "whole inhabited world." In fact Cape St. Vincent is more westerly, but because it is further north, and Strabo's map of the Iberian Peninsula is rotated clockwise, bringing

936-676: Is the southwesternmost point in Portugal. It forms the southwestern end of the E9 European Coastal Path , which runs for 5,000 km (3,100 mi) to Narva-Jõesuu in Estonia . Approximately six kilometers from the village of Sagres, the cape is a landmark for a ship traveling to or from the Mediterranean . The cliffs rise nearly vertically from the Atlantic to a height of 75 meters. The cape

988-538: Is the southwesternmost point of Portugal and of mainland Europe . Cape St. Vincent was already sacred ground in Neolithic times, as standing menhirs in the neighborhood attest. The ancient Greeks called it Ophiussa (Land of Serpents ), inhabited by the Oestriminis and dedicated here a temple to Heracles . The Romans called it Promontorium Sacrum (or Holy Promontory). Strabo, in his Geography calls this cape

1040-502: Is used to measure many parameters (physical values), including: The history of instrumentation can be divided into several phases. Elements of industrial instrumentation have long histories. Scales for comparing weights and simple pointers to indicate position are ancient technologies. Some of the earliest measurements were of time. One of the oldest water clocks was found in the tomb of the ancient Egyptian pharaoh Amenhotep I , buried around 1500 BCE. Improvements were incorporated in

1092-470: Is well known. The broad generalizations and theories which have arisen from time to time have stood or fallen on the basis of accurate measurement, and in several instances new instruments have had to be devised for the purpose. There is little evidence to show that the mind of modern man is superior to that of the ancients. His tools are incomparably better." Davis Baird has argued that the major change associated with Floris Cohen ' s identification of

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1144-602: The Pyrenees into a north–south line, it could have been taken as further east. The most westerly point of the Iberian Peninsula and of the European continent is Cabo da Roca , near Sintra ; the southernmost, Punta de Tarifa , in Andalusia . The rocks at the base of the Cape St. Vincent lighthouse are called "fim do mundo", or "end of the world". Strabo reports (Book 3.1.4) as follows: The region adjacent to this cape they call in

1196-417: The 1970s. The transformation of instrumentation from mechanical pneumatic transmitters, controllers, and valves to electronic instruments reduced maintenance costs as electronic instruments were more dependable than mechanical instruments. This also increased efficiency and production due to their increase in accuracy. Pneumatics enjoyed some advantages, being favored in corrosive and explosive atmospheres. In

1248-469: The 20th-century restorers). It is unlikely to date back to the time of Henry the Navigator. The much-restored church Nossa Senhora da Graça dates from 1579. It replaced the original church of Henry the Navigator of 1459. It was also damaged by the earthquake of 1755. Some alterations to the church were made, such as the building of a new bell tower over the old charnel house of the cemetery. There are still

1300-684: The Latin tongue Cuneum , which signifies a wedge. The promontory which projects into the sea, Artemidorus (who states that he has himself been at the place) compares to a ship; three little islands, each having a small harbour, contribute to give it this form; the former island resembling the beak of the ship, and the two latter the beams on each side of the ship's bows ... there is no temple of Hercules shown there, as Ephorus falsely states, nor yet any altar nor to any other divinity; but in many parts there are three or four stones placed together, which are turned by all travellers who arrive there, in accordance with

1352-463: The Portuguese Age of Discoveries , at his Vila do Infante , Sagres peninsula lacked the necessary requirements for such large undertakings. Fresh water was scarce, agriculture was minimal, there was a shortage of wood for shipbuilding, no deep-water landing site, and the population was small. Henry re-populated a village called Terçanabal, which had been deserted due to continuous pirate attacks on

1404-587: The best nautical information. This probably led to the legend of the Nautical School of Sagres (although a "school" also means a group of followers). There was no centre of navigational science or any supposed observatory , if compared to the modern definition of "observatory" or "navigational centre". The centre of his expeditions was actually at Lagos , further to the east along the Algarve coast. Later Portuguese voyages left from Belém , just west of Lisbon. This

1456-600: The biomedical instrumentation of laboratory rats has very different concerns than the expert in rocket instrumentation. Common concerns of both are the selection of appropriate sensors based on size, weight, cost, reliability, accuracy, longevity, environmental robustness, and frequency response. Some sensors are literally fired in artillery shells. Others sense thermonuclear explosions until destroyed. Invariably sensor data must be recorded, transmitted or displayed. Recording rates and capacities vary enormously. Transmission can be trivial or can be clandestine, encrypted and low power in

1508-484: The clocks. By 270 BCE they had the rudiments of an automatic control system device. In 1663 Christopher Wren presented the Royal Society with a design for a "weather clock". A drawing shows meteorological sensors moving pens over paper driven by clockwork. Such devices did not become standard in meteorology for two centuries. The concept has remained virtually unchanged as evidenced by pneumatic chart recorders, where

1560-405: The coast. The village was situated in a strategic position for his maritime enterprises and was later called Vila do Infante . Henry the Navigator employed cartographers, such as Jehuda Cresques , to help him chart the coast of Mauretania in the wake of voyages he had caused to be made to there. He also engaged an expert map and instrument-maker, Jayme of Majorca, so that his captains might have

1612-479: The control racks to be networked and thereby located locally to plant to reduce cabling runs, and provided high level overviews of plant status and production levels. In some cases, the sensor is a very minor element of the mechanism. Digital cameras and wristwatches might technically meet the loose definition of instrumentation because they record and/or display sensed information. Under most circumstances neither would be called instrumentation, but when used to measure

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1664-435: The early years of process control , process indicators and control elements such as valves were monitored by an operator, that walked around the unit adjusting the valves to obtain the desired temperatures, pressures, and flows. As technology evolved pneumatic controllers were invented and mounted in the field that monitored the process and controlled the valves. This reduced the amount of time process operators needed to monitor

1716-435: The eastern side of Sagres Point is a harbor, Baleeira, port of the modern town of Sagres, protected by four small islands in a line (the tiny Martinhal Islets) visible in satellite imagery. At the far eastern end of the beach of Martinhal, erosion of the cliffs has exposed a series of Roman pottery kilns for fabricating transport amphoras and roof tiles. When Henry the Navigator commenced his explorations, which would initiate

1768-409: The elapsed time of a race and to document the winner at the finish line, both would be called instrumentation. A very simple example of an instrumentation system is a mechanical thermostat , used to control a household furnace and thus to control room temperature. A typical unit senses temperature with a bi-metallic strip . It displays temperature by a needle on the free end of the strip. It activates

1820-464: The explorers to claim a newly discovered territory. 37°00′23″N 8°56′21″W  /  37.00639°N 8.93917°W  / 37.00639; -8.93917 Cape St. Vincent Cape St. Vincent ( Portuguese : Cabo de São Vicente , Portuguese pronunciation: [ˈkaβu ðɨ sɐ̃w viˈsẽtɨ] ) is a headland in the municipality of Vila do Bispo , in the Algarve , southern Portugal . It

1872-406: The furnace by a mercury switch . As the switch is rotated by the strip, the mercury makes physical (and thus electrical) contact between electrodes. Another example of an instrumentation system is a home security system . Such a system consists of sensors (motion detection, switches to detect door openings), simple algorithms to detect intrusion, local control (arm/disarm) and remote monitoring of

1924-408: The goal of improving system productivity , reliability, safety, optimization and stability. To control the parameters in a process or in a particular system, devices such as microprocessors, microcontrollers or PLCs are used, but their ultimate aim is to control the parameters of a system. Instrumentation engineering is loosely defined because the required tasks are very domain dependent. An expert in

1976-446: The graphic display in the control room or rooms. The distributed control concept was born. The introduction of DCSs and SCADA allowed easy interconnection and re-configuration of plant controls such as cascaded loops and interlocks, and easy interfacing with other production computer systems. It enabled sophisticated alarm handling, introduced automatic event logging, removed the need for physical records such as chart recorders, allowed

2028-496: The information may be transferred to a crash recorder to aid mishap investigations. Modern pilot displays now include computer displays including head-up displays . Air traffic control radar is a distributed instrumentation system. The ground part sends an electromagnetic pulse and receives an echo (at least). Aircraft carry transponders that transmit codes on reception of the pulse. The system displays an aircraft map location, an identifier and optionally altitude. The map location

2080-416: The most western tip of the known world and reports the place was considered magical. Common people believed the sun sank here hissing into the ocean, marking the edge of their world, which Strabo qualifies as "common and vulgar reports" and attributes to Posidonius According to legend, the current name of this cape is linked to the story of a martyred fourth-century Iberian deacon St. Vincent whose body

2132-439: The need to control valves and actuators in the field. Typically, a signal ranged from 3 to 15 psi (20 to 100kPa or 0.2 to 1.0 kg/cm2) as a standard, was standardized with 6 to 30 psi occasionally being used for larger valves. Transistor electronics enabled wiring to replace pipes, initially with a range of 20 to 100mA at up to 90V for loop powered devices, reducing to 4 to 20mA at 12 to 24V in more modern systems. A transmitter

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2184-593: The presence of jamming. Displays can be trivially simple or can require consultation with human factors experts. Control system design varies from trivial to a separate specialty. Instrumentation engineers are responsible for integrating the sensors with the recorders, transmitters, displays or control systems, and producing the Piping and instrumentation diagram for the process. They may design or specify installation, wiring and signal conditioning. They may be responsible for commissioning, calibration, testing and maintenance of

2236-451: The process indicators. This again reduced the number and amount of time process operators were needed to walk around the units. The most standard pneumatic signal level used during these years was 3–15 psig. Process control of large industrial plants has evolved through many stages. Initially, control would be from panels local to the process plant. However, this required a large manpower resource to attend to these dispersed panels, and there

2288-410: The process. Latter years, the actual controllers were moved to a central room and signals were sent into the control room to monitor the process and outputs signals were sent to the final control element such as a valve to adjust the process as needed. These controllers and indicators were mounted on a wall called a control board. The operators stood in front of this board walking back and forth monitoring

2340-408: The productive and destructive potential inherent in process control. The ability to make precise, verifiable and reproducible measurements of the natural world, at levels that were not previously observable, using scientific instrumentation, has "provided a different texture of the world". This instrumentation revolution fundamentally changes human abilities to monitor and respond, as is illustrated in

2392-494: The relics is depicted on the coat of arms of Lisbon . All existing buildings—including the Vila do Infante of Henry the Navigator —fell into ruins because of the Lisbon earthquake of 1755. The Franciscan friars who cared for the shrine stayed on until 1834, when all monasteries were disbanded in Portugal. Several naval battles have been fought in the vicinity of this cape: This cape

2444-731: The system so that the police can be summoned. Communication is an inherent part of the design. Kitchen appliances use sensors for control. Modern automobiles have complex instrumentation. In addition to displays of engine rotational speed and vehicle linear speed, there are also displays of battery voltage and current, fluid levels, fluid temperatures, distance traveled, and feedback of various controls (turn signals, parking brake, headlights, transmission position). Cautions may be displayed for special problems (fuel low, check engine, tire pressure low, door ajar, seat belt unfastened). Problems are recorded so they can be reported to diagnostic equipment . Navigation systems can provide voice commands to reach

2496-408: The system. In a research environment it is common for subject matter experts to have substantial instrumentation system expertise. An astronomer knows the structure of the universe and a great deal about telescopes – optics, pointing and cameras (or other sensing elements). That often includes the hard-won knowledge of the operational procedures that provide the best results. For example, an astronomer

2548-522: The world's busiest shipping lanes, is among the most powerful in Europe (the most powerful being Phare du Creach on the French island of Ushant , off the coast of Brittany ); its two 1,000 W lamps can be seen as far as 60 kilometres (37 mi) away. Cape St. Vincent has a Mediterranean climate with very low seasonal variation and high occurrence of fogs . Measuring instrument Instrumentation

2600-566: Was a time of many important discoveries: cartography was being refined with the use of newly devised instruments , such as an improved astrolabe and improved sundial , maps were regularly being updated and extended, and a revolutionary type of vessel known as the caravel was designed. Prince Henry built a chapel next to his house in 1459, as he began to spend more time in the Sagres area in his later years. He died at Sagres on 13 November 1460. The exact location of Henry's School of Navigation

2652-501: Was brought ashore here. A shrine was erected over his grave; according to the Arab geographer Al-Idrisi , it was always guarded by ravens and is therefore named by him كنيسة الغراب ( Kanīsah al-Ghurāb , meaning "Church of the Raven"). King Afonso Henriques (1139–1185) had the body of the saint exhumed in 1173 and brought it by ship to Lisbon , still accompanied by the ravens. This transfer of

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2704-469: Was no overall view of the process. The next logical development was the transmission of all plant measurements to a permanently staffed central control room. Effectively this was the centralization of all the localized panels, with the advantages of lower manning levels and easy overview of the process. Often the controllers were behind the control room panels, and all automatic and manual control outputs were transmitted back to plant. However, whilst providing

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