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88-493: Paddington Tramways Substation is a heritage-listed former electrical substation at 150 Enoggera Terrace, Paddington , City of Brisbane , Queensland , Australia. It was designed by Roy Rusden Ogg and built from 1929 to 1930. It was added to the Queensland Heritage Register on 22 March 1993. The former tramways substation was erected in 1929–30, during a period of tramways expansion which followed

176-447: A bus plus some circuit breakers . The largest transmission substations can cover a large area (several acres/hectares) with multiple voltage levels, many circuit breakers, and a large amount of protection and control equipment ( voltage and current transformers , relays and SCADA systems). Modern substations may be implemented using international standards such as IEC Standard 61850 . A distribution substation transfers power from

264-401: A contractor or alternately all phases of its development may be handled by the electrical utility . Most commonly, the utility does the engineering and procurement while hiring a contractor for actual construction. Major design constraints for construction of substations include land availability and cost, limitations on the construction period, transportation restrictions, and the need to get

352-475: A 3 x safety factor applied. While major wiring may not be the focus, residential use of raised floors and split levels in 12-foot-ceiling (3.7 m) Manhattan apartments provides " high-performance elements" and added functionality. To remove panels, a tool with a suction cup on the end (referred to as a "floor puller", "tile lifter", or "suction lifter") is used. A hook-and-loop lifter may be used on carpeted panels. Low-profile fixed height access flooring

440-428: A better distribution of power to the increased western suburbs tram services. Considerable attention was given to the design of these substations. Roy Rusden Ogg , the tramways' architect and construction engineer from 1926 until the late 1930s, in conjunction with tramways' chief engineers William Muir Nelson (1925–26) and William Arundell (1926–49?), designed at least ten Brisbane substations between 1926 and 1936, and

528-449: A central pilaster. The building has a heavy cornice , feature panels of rough render and a base which is scribed to suggest large size stone blocks. The building has large sash windows with mottled glass panes with a panel of galvanised iron louvres to either side of each window. There are also ventilation panels in the base and below the cornice. A set of large timber doors is located on the north, which has been painted bright colours, and

616-706: A disconnection of the load supplied by the circuit break from the feeding point. This seeks to isolate the fault point from the rest of the system, and allow the rest of the system to continue operating with minimal impact. Both switches and circuit breakers may be operated locally (within the substation) or remotely from a supervisory control center. With overhead transmission lines , the propagation of lightning and switching surges can cause insulation failures into substation equipment. Line entrance surge arrestors are used to protect substation equipment accordingly. Insulation Coordination studies are carried out extensively to ensure equipment failure (and associated outages )

704-587: A floor whereas lower panels can be used on lighter areas. Many such problems can be attributed to sub-par installation. During installation, attention should be paid to the condition of the subfloor, which should be clean of debris and should be as level as possible. The walls surrounding the raised floor should be as square as possible to minimize the need for cutting raised floor panels and to minimize rocking panels and gaps. Low-profile, fixed-height systems accommodate irregularly shaped rooms with adjustable border components that minimizes cutting of panels. Because

792-536: A gridded metal framework or substructure of adjustable-height supports (called "pedestals") that provide support for removable (liftable) floor panels, which are usually 2 by 2 feet (0.61 m × 0.61 m). The height of the legs/pedestals is dictated by the volume of cables and other services provided beneath, but typically arranged for a clearance of at least 6 inches (150 mm) with typical heights between 24 and 48 inches (610 and 1,220 mm). The panels are normally made of steel - clad particleboard or

880-405: A history and a set of specifications. Telcordia NEBS: Raised Floor Generic Requirements for Network and Data Centers , GR-2930 presents generic engineering requirements for raised floors that fall within the strict NEBS guidelines. There are many types of commercially available floors that offer a wide range of structural strength and loading capabilities, depending on component construction and

968-457: A large substation, circuit breakers are used to interrupt any short circuits or overload currents that may occur on the network. Smaller distribution stations may use recloser circuit breakers or fuses for protection of distribution circuits. Substations themselves do not usually have generators, although a power plant may have a substation nearby. Other devices such as capacitors , voltage regulators , and reactors may also be located at

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1056-522: A long lease such as a renewable 99-year lease, giving the utility company security of tenure . The first step in planning a substation layout is the preparation of a one-line diagram , which shows in simplified form the switching and protection arrangement required, as well as the incoming supply lines and outgoing feeders or transmission lines. It is a usual practice by many electrical utilities to prepare one-line diagrams with principal elements (lines, switches, circuit breakers, transformers) arranged on

1144-589: A prominent urban location. The building has a special association with the work of tramways architect RR Ogg and chief engineer W Arundell. The place is important because of its aesthetic significance. The substation exhibits a landmark quality and contribution to the Brisbane townscape which is valued by the community. The place has a strong or special association with a particular community or cultural group for social, cultural or spiritual reasons. The building has strong social and cultural associations with

1232-690: A ring bus, double bus, or so-called "breaker and a half" setup can be used, so that the failure of any one circuit breaker does not interrupt power to other circuits, and so that parts of the substation may be de-energized for maintenance and repairs. Substations feeding only a single industrial load may have minimal switching provisions, especially for small installations. Because of the risk of electrical shock, substations are inherently dangerous to electrical workers. To mitigate this hazard, substations are designed with various safety features. Live conductors and bare equipment are kept separate, either with protected equipment, or using screens or distance. Based on

1320-400: A section of the base has also been painted. Internally the building has concrete floors, painted brick walls and steel beams to the roof, with metal covers to the panels of louvres and pink glass inserts to the centre of the sash windows. The east end of the space has a raised floor accessed via a steep metal stair with a more recent steel pipe railing. The original arrangement of equipment

1408-498: A single facility. When underfloor air is designed into a building from the start of the project, the building can be less expensive to build and less expensive to operate over the life of the building. Underfloor air requires less space per floor, thereby reducing the overall height of the building, which in turn reduces the cost of the building facade. The blowers and air handlers required for underfloor air are much smaller and require less energy, since hot air rises naturally through

1496-440: A steel panel with a cementitious internal core, although some tiles have hollow cores. Panels may be covered with a variety of flooring finishes to suit the application, such as carpet tiles, high-pressure laminates , marble , stone , and antistatic finishes for use in computer rooms and laboratories . When using a panel with a cement top surface the panels are sometimes left bare and sealed or stained and sealed to create

1584-679: A substation. Substations may be on the surface in fenced enclosures, underground, or special-purpose buildings. High-rise buildings may have several indoor substations. Indoor substations are usually found in urban areas to reduce the noise from transformers, improve appearance, or protect switchgear from extreme climate or pollution. Substations often use busbars as conductors between electrical equipment. Busbars may be aluminum tubing 3–6 inches (76–152 mm) thick, or else wires (strain bus). Outdoor, above-ground substation structures include wood pole, lattice metal tower, and tubular metal structures, although other variants are available. Where space

1672-585: A tile appearance and save the customer money. This bare application is used most often in office area, hallways, lobbies, museums, casinos, etc. A contemporary low-profile fixed height type of cable management access floor differs from traditional access floor by requiring much less ramping floor space at floor height transitions, and can even be eliminated in new construction with slab depressions. The primary advantages are realized by much lighter weight panels for easier handling. No tools are required to make changes, and organized cable channel pathways are integral to

1760-563: A tramway was extended along Musgrave Road to Red Hill , and a line was laid along Caxton Street and Given Terrace as far as Latrobe Terrace in 1898. The Red Hill line was extended to Ashgrove in 1924, and the Paddington line was extended to Bardon in 1937. The spread of the tramways network was a catalyst for residential development in the western suburbs. In 1926 the Greater Brisbane Council, anxious to control

1848-422: A transmission line or a transformer. To maintain reliability of supply, companies aim at keeping the system up and running while performing maintenance. All work to be performed, from routine testing to adding entirely new substations, should be done while keeping the whole system running. Unplanned switching events are caused by a fault in a transmission line or any other component, for example: The function of

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1936-499: A wider range of applications where underfloor air distribution is not utilized. In 2009 a separate category of raised floor was established by Construction Specifications Institute (CSI) and Construction Specifications Canada (CSC) to separate the similar, but very different, approaches to raised flooring. In this case the term raised floor includes low-profile fixed-height access flooring. Offices , classrooms , conference rooms , retail spaces , museums , studios , and more, have

2024-402: Is 8 kilonewtons per square metre (kN/m ) uniformly distributed load (UDL) and a 3.0 kN point load. There is an additional 3 x safety factor applied to the loadings. Computer and control rooms including data centers generally have a higher requirement with regards to static loadings and PSA heavy grade should be employed. This provides 12 kN/m UDL and a 4.5 kN point load, again with

2112-400: Is a requirement to route mechanical services and cables, wiring , and electrical supply. Such flooring can be installed at varying heights from 2 inches (51 mm) to heights above 4 feet (1.2 m) to suit services that may be accommodated beneath. Additional structural support and lighting are often provided when a floor is raised enough for a person to crawl or even walk beneath. In

2200-602: Is aimed at minimizing cost while ensuring power availability and reliability, and enabling changes to the substation in the future. Substations may be built outdoors, indoors, or underground or in a combination of these locations. Selection of the location of a substation must consider many factors. Sufficient land area is required for installation of equipment with necessary clearances for electrical safety, and for access to maintain large apparatus such as transformers. The site must have room for expansion due to load growth or planned transmission additions. Environmental effects of

2288-465: Is common in the area. The output is a number of feeders. Distribution voltages are typically medium voltage, between 2.4 kV and 33 kV, depending on the size of the area served and the practices of the local utility. The feeders run along streets overhead (or underground, in some cases) and power the distribution transformers at or near the customer premises. In addition to transforming voltage, distribution substations also isolate faults in either

2376-416: Is considered to be the most densely populated in terms of square foot area and, therefore, the largest floor load anticipated for a raised floor system. Considering prorated aisle space, a single equipment cabinet will then occupy an 8-square-foot (0.74 m ) floor area (4 sq ft or 0.37 m for the cabinet and 4 sq ft of aisle). The data center can be located in remote locations, and

2464-407: Is evident. Floor ducting for the power supply is located in the west end of the space but has been filled in. The high tension switchgear and 1100 KVA transformer have been removed. The upper level has a concrete platform, supported on brick piers, where the rotary converter was located. The original location of the relay panel can be seen against the south wall, and the control and feeder panel against

2552-618: Is green. Common Applications: Raised access flooring is commonplace in office accommodation, retail spaces, computer and control rooms. There are two bench-marks for performance testing in the United Kingdom, These being the PSA MOB PF2 PS (spu) 1992 and the more recent, slightly less stringent BS/EN12825 . These set out defined static loading criteria for the raised access floor to meet. The maximum for raised access flooring for general office accommodation (PSA medium grade)

2640-569: Is held in place by gravity without glue or fasteners and does not require any tools to make changes. Structural problems, such as rocking panels and gaps between panels, can cause significant damage to equipment and injury to personnel. Regular inspections for the structural integrity of a raised floor system can help to identify and mitigate problems. Equipment and floor damage can happen when using flooring that does not meet load demands. Load ratings range from 1,000 to 25,000 pounds (0.45–11.34 t). Higher panels can be used on heavier areas of

2728-402: Is minimal. Once past the switching components, the lines of a given voltage connect to one or more buses . These are sets of busbars , usually in multiples of three, since three-phase electrical power distribution is largely universal around the world. The arrangement of switches, circuit breakers, and buses used affects the cost and reliability of the substation. For important substations

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2816-474: Is necessary to work on parts of the substation while energized, but employees must maintain a safe distance of at least 3 metres (9.8 ft). The aim to reduce substation footprints comes into conflict with ease of maintenance enhanced by including gaps where employees can safely work. Underneath a substation, a mat or grid of conductors laid around 0.5 or 0.6 metres (1 ft 8 in or 2 ft 0 in) underground provides grounding . This grid, which

2904-681: Is not required. Many modern computer and equipment rooms employ an underfloor air distribution to ensure even cooling of the room with minimal wasted energy. Conditioned air is provided under the floor and dispersed upward into the room through regularly spaced diffuser tiles, blowers or through ducts directed into specific equipment. Automatic fire protection shutoffs may be required for underfloor ventilation , and additional suppression systems may be installed in case of underfloor fires . Many office buildings use access flooring to create more flexible and sustainable spaces. A large corporation can have over 20,000 miles (32,000 km) of cabling in

2992-472: Is plentiful and appearance of the station is not a factor, steel lattice towers provide low-cost supports for transmission lines and apparatus. Low-profile substations may be specified in suburban areas where appearance is more critical. Indoor substations may be gas insulated substations (GIS) (at high voltages, with gas insulated switchgear), or use metal-enclosed or metal-clad switchgear at lower voltages. Urban and suburban indoor substations may be finished on

3080-414: Is subject to physical and electrical stresses from sources such as fires and from electrical faults. The environment drives the installation methods for raised floors, including site preparation, cable and cable racking, bonding and grounding, and fire resistance. The actual installation should be in accordance with the customer's practices. Raised floors for Data centers , and in particular rooms, have

3168-617: Is towards 80–100 cm (31–39 in) void to cater for better and uniform air distribution. These provide a plenum for air to circulate below the floor, as part of the air conditioning system, as well as providing space for power cabling. Raised floors and other metal structures such as cable trays and ventilation ducts have caused many problems with zinc whiskers in the past, and likely are still present in many data centers. This happens when microscopic metallic filaments form on metals such as zinc or tin that protect many metal structures and electronic components from corrosion. Maintenance on

3256-451: Is typically copper although it may be galvanized iron in some countries, is used to ground circuits that are being worked on to prevent accidental re-energization while workers are in contact with a de-energized circuit. Often, earth rods are driven deeper into the ground from the grounding grid for lower resistance grounding, and may be surrounded by bentonite or marconite to further reduce resistance and ensure effective grounding for

3344-410: Is used as a protection device to interrupt fault currents automatically, and may be used to switch loads on and off, or to cut off a line when power is flowing in the 'wrong' direction. When a large fault current flows through the circuit breaker, this is detected through the use of current transformers . The magnitude of the current transformer outputs may be used to trip the circuit breaker resulting in

3432-618: Is where all transmission lines have the same voltage. In such cases, substation contains high-voltage switches that allow lines to be connected or isolated for fault clearance or maintenance. A transmission station may have transformers to convert between two transmission voltages, voltage control / power factor correction devices such as capacitors, reactors or static VAR compensators and equipment such as phase shifting transformers to control power flow between two adjacent power systems. Transmission substations can range from simple to complex. A small "switching station" may be little more than

3520-519: The "Queensland heritage register boundaries" published by the State of Queensland under CC-BY 3.0 AU licence (accessed on 5 September 2014, archived on 15 October 2014). Electrical substation Substations may be owned and operated by an electrical utility, or may be owned by a large industrial or commercial customer. Generally substations are unattended, relying on SCADA for remote supervision and control. The word substation comes from

3608-698: The Brisbane City Council 's 1925 acquisition of the tramways system from the Brisbane Tramways Trust . It was erected on Cook's Hill, along the Paddington Line, on land which was formerly part of the adjacent Ithaca Fire Station . The Brisbane Tramways Company, a private enterprise formed in 1895, introduced the first electric trams to Brisbane in mid-1897. Following lobbying by the Ithaca Shire Council ,

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3696-416: The microprocessor made for an exponential increase in the number of points that could be economically controlled and monitored. Today, standardized communication protocols such as DNP3 , IEC 61850 and Modbus , to list a few, are used to allow multiple intelligent electronic devices to communicate with each other and supervisory control centers. Distributed automatic control at substations is one element of

3784-465: The Czech Republic, where power is collected from nearby lignite -fired power plants. If no transformers are required for increasing the voltage to transmission level, the substation is a switching station. Converter substations may be associated with HVDC converter plants, traction current , or interconnected non-synchronous networks. These stations contain power electronic devices to change

3872-547: The Paddington community, being an integral member of an historic group of sites on Cook's Hill which includes the former Ithaca Fire Station , the Ithaca War Memorial , and Ithaca Embankments . [REDACTED] This Misplaced Pages article was originally based on "The Queensland heritage register" published by the State of Queensland under CC-BY 3.0 AU licence (accessed on 7 July 2014, archived on 8 October 2014). The geo-coordinates were originally computed from

3960-494: The U.S., underfloor air distribution is becoming a more common way to cool a building by using the void below the raised floor as a plenum chamber to distribute conditioned air, which has been done in Europe since the 1970s. In data centers, isolated air-conditioning zones are often associated with raised floors. Perforated tiles are traditionally placed beneath computer systems to direct conditioned air directly to them. In turn,

4048-591: The amps exceed a certain amount over a period of time. Reclosers will attempt to re-energize the circuit after a delay. If unsuccessful for a few times, the recloser will have to be manually reset by an electrical worker. Capacitor banks are used in substations to balance the lagging current draw from inductive loads (such as motors, transformers, and some industrial equipment) with their reactive load . Additional capacitor capacity may be needed if dispersed generation (such as small diesel generators, rooftop photovoltaic solar panels , or wind turbines ) are added to

4136-434: The building and was running monthly "vintage and artisan" markets. The former tramway substation is a rendered masonry building with a flat concrete roof behind a parapet wall. It is situated prominently adjacent to the intersection of Latrobe and Enoggera Terraces. The symmetrical facades demonstrate a classical influence in their design. The building has corner pilasters with the longer north and south elevations having

4224-467: The building by reducing the interaction between the heat gains and the thermally massive concrete slab. The raised floor serves as a separation between the room and the slab. Energy simulations of an office building located in San Francisco showed that the mere presence of the raised floor affects the zone cooling load profile and tends to increase the peak cooling load. When carpeting is present

4312-654: The city's electricity supply, decided to build the Brisbane Powerhouse at New Farm , under the supervision of the BCC Tramways Department. Opened on 28 June 1928, New Farm distributed 11000 volts AC power to a network of eleven suburban tramway substations erected in the 1920s and 1930s. The function of the Paddington substation, the seventh in the network, was to assist the Petrie Terrace substation (erected 1927–28) in providing

4400-587: The complexity of distribution networks grew, it became economically necessary to automate supervision and control of substations from a centrally attended point, to allow overall coordination in case of emergencies and to reduce operating costs. Early efforts to remote control substations used dedicated communication wires, often run alongside power circuits. Power-line carrier , microwave radio , fiber optic cables as well as dedicated wired remote control circuits have all been applied to Supervisory Control and Data Acquisition (SCADA) for substations. The development of

4488-472: The computing equipment is often designed to draw cooling air from below and exhaust into the room. An air conditioning unit then draws air from the room, cools it, and forces it beneath the raised floor, completing the cycle. Above describes what has historically been perceived as raised floor and still serves the purpose for which it was originally designed. Decades later, an alternative approach to raised floor evolved to manage underfloor cable distribution for

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4576-477: The current to back-up lines or for parallelizing circuits in case of failure. An example is the switching stations for the HVDC Inga–Shaba transmission line. A switching station may also be known as a switchyard, and these are commonly located directly adjacent to or nearby a power station . In this case the generators from the power station supply their power into the yard onto the generator bus on one side of

4664-446: The days before the distribution system became a grid . As central generation stations became larger, smaller generating plants were converted to distribution stations, receiving their energy supply from a larger plant instead of using their own generators. The first substations were connected to only one power station , where the generators were housed, and were subsidiaries of that power station. Substations may be designed and built by

4752-406: The east wall which remain intact with insulators. An AC transformer is located externally to the west. On the western perimeter is a section of stone wall which was part of the gardens originally located on the site. The Paddington Tramways Substation was listed on the Queensland Heritage Register on 22 March 1993 having satisfied the following criteria. The place is important in demonstrating

4840-439: The east wall which supplied power to the feeder cables located either end at the top of the east wall. A toilet cubicle is located in the southeast corner of the space, over which an air compressor was once situated. An overhead gantry crane is still intact. A low exit door has been cut in the south wall, at a later date, and has an external timber access stair. The feeder cables were supported externally by large curved brackets on

4928-416: The equipment used to monitor, control, and protect the rest of the substation equipment. It often contains protective relays, meters, breaker controls, communications, batteries, and recorders that save detailed data about substation operations, particularly when there is any unusual activity, to help reconstruct what happened after the fact. These control rooms typically are heated and air conditioned to ensure

5016-519: The evolution or pattern of Queensland's history. The Paddington Substation is important in demonstrating part of the evolution and pattern of Queensland's history, in that it provides evidence of Brisbane's early 20th century tramway system and its contribution to the growth of the inner western suburbs; and has had a close association with the development of Brisbane's electricity supply system. The place demonstrates rare, uncommon or endangered aspects of Queensland's cultural heritage. In elements of

5104-430: The fabric and design, the building demonstrates now rare evidence of the electrical system arrangement and working of an interwar, rotary converter type, tramways substation in Brisbane. The place is important in demonstrating the principal characteristics of a particular class of cultural places. The substation is important in demonstrating the principal characteristics of a small scale industrial building designed for

5192-555: The first two stages of the New Farm powerhouse (1927–29 and 1934–36). Ogg also designed the Tramways Department's Head Office building on Coronation Drive (1929). The Paddington substation, constructed of bricks and structural steel from the old Countess Street power house (closed in mid-1928), was the first of his substation designs to incorporate a parapet wall, flat roof and exterior render. The Paddington substation

5280-411: The flooring tiles are rarely removed once equipment has been installed, the space below them is seldom cleaned, and fluff and other debris settles, making working on cabling underneath the flooring a dirty job. Smoke detectors under the raised floor can be triggered by workers disturbing the dust , resulting in false alarms . The installation of a raised floor system can change the thermal behavior of

5368-425: The frequency of current, or else convert from alternating to direct current or the reverse. Formerly rotary converters changed frequency to interconnect two systems; nowadays such substations are rare. A switching station is a substation without transformers and operating only at a single voltage level. Switching stations are sometimes used as collector and distribution stations. Sometimes they are used for switching

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5456-408: The jurisdiction or company, there are safety standards with minimum required clearance between different live equipment or conductors or between live metal and the ground, which often varies with higher clearance being required for higher voltages because of the greater ability to generate flashover . To this is added the necessary space for employees to work safely and vehicles to pass. Sometimes it

5544-590: The lifetime of the substation. Above ground, the grounding conductors may be steel, aluminum, or copper. They must be thick enough to carry the expected current of a fault for 1-3 seconds and remain undamaged. Substation fences, typically at least 2 metres (6 ft 7 in) in height, both protect the public from electrical hazards and also protect the substation from vandalism. Internal fences can also be incorporated to protect employees from areas that are unsafe when energized. Substations generally have switching, protection and control equipment, and transformers. In

5632-411: The low-voltage side. More typical distribution substations have a switch, one transformer, and minimal facilities on the low-voltage side. In distributed generation projects such as a wind farm or photovoltaic power station , a collector substation may be required. It resembles a distribution substation although power flow is in the opposite direction, from many wind turbines or inverters up into

5720-582: The materials used. The general types of raised floors include stringer, stringerless, and structural platforms, all of which are discussed in detail in GR-2930. This design permits equipment to be fastened directly to the platform without the need for toggle bars or supplemental bracing. Structural platforms may or may not contain panels or stringers; they are not recommend in earthquake-prone locations. Data centers typically have raised flooring made up of 60 cm (2 ft) removable square tiles. The trend

5808-669: The negative impact of the raised floor on zone peak cooling load may be reduced. Raised floors available for general purpose use typically do not address the special requirements needed for telecommunications applications. The general types of raised floors in telecommunications data centers include: stringerless, stringered, and structural platforms; and, truss assemblies. A telecommunications facility may contain continuous lineups of equipment cabinets. The most densely populated installation configuration would consist of rows of continuous 2-foot-wide equipment cabinets with aisles that separate 2-foot-wide adjacent rows. This lineup configuration

5896-411: The outside so as to blend in with other buildings in the area. A compact substation is generally an outdoor substation built in a metal enclosure, in which each item of the electrical equipment is located very near to each other to create a relatively smaller footprint size of the substation. High-voltage circuit breakers are commonly used to interrupt the flow of current in substation equipment. At

5984-407: The page similarly to the way the apparatus would be laid out in the actual station. In a common design, incoming lines have a disconnect switch and a circuit breaker . In some cases, the lines will not have both, with either a switch or a circuit breaker being all that is considered necessary. A disconnect switch is used to provide isolation, since it cannot interrupt load current. A circuit breaker

6072-553: The primary need to quickly and easily accommodate changes of technology and floor plan configurations. Underfloor air distribution is not included in this approach since a plenum chamber is not created. The low-profile fixed-height distinction reflects the system's height ranges from as low as 1.6 to 2.75 inches (41 to 70 mm); and the floor panels are manufactured with integral support (not traditional pedestals and panels). Cabling channels are directly accessible under light-weight cover plates. The traditional type of floor consists of

6160-661: The public grid. Sometimes they are also transmission substations or collector substations if the railway network also operates its own grid and generators to supply the other stations. A mobile substation is a substation on wheels, containing a transformer, breakers and buswork mounted on a self-contained semi-trailer , meant to be pulled by a truck . They are designed to be compact for travel on public roads, and are used for temporary backup in times of natural disaster or war . Mobile substations are usually rated much lower than permanent installations, and may be built in several units to meet road travel limitations. Substation design

6248-411: The reliable operation of this equipment. Additional equipment is necessary to handle power surges associated with intermittent renewable energy such as dispersed generation from wind or solar. Most transformers lose between 5 and 1.5 percent of their input as heat and noise. Iron losses are no-load and constant whenever the transformer is energized, while copper and auxiliary losses are proportionate to

6336-496: The so-called smart grid . Raised floor A raised floor (also raised flooring , access floor(ing), or raised-access computer floor ) provides an elevated structural floor above a solid substrate (often a concrete slab) to create a hidden void for the passage of mechanical and electrical services. Raised floors are widely used in modern office buildings , and in specialized areas such as command centers , Information technology data centers and computer rooms , where there

6424-735: The space as it comes in contact with people and equipment that warm the air and it rises to the ceiling. Additionally, when buildings are designed to combine modular electrical, modular walls, and access floor, the space within the building can be reconfigured in a few hours, as compared to historical means of demolishing walls and drilling holes in the floor to route electrical and other services. As more companies construct or renovate buildings to meet Leadership in Energy & Environmental Design (LEED) underfloor air and access floor usage will continue to grow. The U.S. Green Building Council (USGBC) states that 40–48 percent of new nonresidential construction

6512-430: The square of the current. Auxiliary losses are due to running fans and pumps which is noisy when the transformer is operating at maximum capacity. To reduce noise, enclosures are often built around the transformer and can also be added after the substation is built. Oil-based transformers are often built with bunded areas to prevent the escape of flaming or leaking oil. Fire separation areas or firewalls are built around

6600-451: The substation must be considered, such as drainage , noise and road traffic effects. The substation site must be reasonably central to the distribution area to be served. The site must be secure from intrusion by passers-by, both to protect people from injury by electric shock or arcs, and to protect the electrical system from misoperation due to vandalism. If not owned and operated by a utility company, substations are typically occupied on

6688-400: The substation running quickly. Prefabrication is a common way to reduce the construction cost. For connecting the new substation, a partial outage at another substation may be required, but the utility often tries to minimize downtime. Substations typically serve at least one of the following purposes: A transmission substation connects two or more transmission lines. The simplest case

6776-454: The substation where electrical energy is being converted to heat, which indicates a problem and can cause additional damage from the high heat. Dissolved gas analysis can tell when an oil-insulated transformer needs to have the oil filtered or replace, and also detect other issues. Early electrical substations required manual switching or adjustment of equipment, and manual collection of data for load, energy consumption, and abnormal events. As

6864-554: The switching station is to isolate the faulty portion of the system in the shortest possible time. De-energizing faulty equipment protects it from further damage, and isolating a fault helps keep the rest of the electrical grid operating with stability. Electrified railways also use substations, often distribution substations. In some cases a conversion of the current type takes place, commonly with rectifiers for direct current (DC) trains, or rotary converters for trains using alternating current (AC) at frequencies other than that of

6952-436: The system. Capacitors can reduce the current in wires, helping stem system losses from voltage drop or enabling extra power to be sent through the conductors. Capacitors may be left on in response to constant inductive load or turned on when inductive load is increased, such as in the summer for air conditioners . The switching may be remote and can be done manually or automatically. Larger substations have control rooms for

7040-411: The system. Time and expense is greatly reduced during installation and every time changes are made in the future during the life of the building. Since this type of access floor is not attached to the structure it is considered to be furnishings, fixtures, and equipment (FF&E) that can be a depreciated expense or leased. Since the underfloor cabling is not in a plenum, the expense of plenum rated cable

7128-466: The time of interruption, current could be normal, too high due to excessive load, unusual due to a fault, or tripped by protective relays prior to anticipated trouble. The most common technologies to extinguish the power arc from separating the conductors in the breaker include: Reclosers are similar to breakers, and can be cheaper because they do not require separate protective relays. Often used in distribution, they often are programmed to trip when

7216-412: The tramways network. The substation commenced operation on 11 August 1930 and remained in service until the phasing out of Brisbane's trams in the late 1960s. In 1969 the Paddington line was closed, the substation's electrical equipment was removed, and the building became a storage depot. In 1985, Hands On Art was given a fifteen-year lease of the building. In 2014, Hands On Art was still operating from

7304-429: The transformer to stop the spread of fire. Firefighting vehicles are allowed a path to access the area. Maintenance of substations involves inspections, data collection and analysis, and routine scheduled work. Using methods such as infrared scanning and dissolved gas analysis, it can be predicted when the substation will need maintenance and predict dangers before they materialize. Infrared technology finds hot spots in

7392-712: The transmission grid. Usually for economy of construction the collector system operates around 35 kV, although some collector systems are 12 kV, and the collector substation steps up voltage to a transmission voltage for the grid. The collector substation can also provide power factor correction if it is needed, metering, and control of the wind farm. In some special cases a collector substation can also contain an HVDC converter station. Collector substations also exist where multiple thermal or hydroelectric power plants of comparable output power are in proximity. Examples for such substations are Brauweiler in Germany and Hradec in

7480-401: The transmission or distribution systems. Distribution substations are typically the points of voltage regulation , although on long distribution circuits (of several miles/kilometers), voltage regulation equipment may also be installed along the line. The downtown areas of large cities feature complicated distribution substations, with high-voltage switching, and switching and backup systems on

7568-454: The transmission system to the distribution system of an area. It is uneconomical to directly connect electricity consumers to the main transmission network, unless they use large amounts of power, so the distribution station reduces voltage to a level suitable for local distribution. The input for a distribution substation is typically at least two transmission or sub-transmission lines. Input voltage may be, for example, 115 kV, or whatever

7656-462: The yard, and the transmission lines take their power from a Feeder Bus on the other side of the yard. An important function performed by a substation is switching , which is the connecting and disconnecting of transmission lines or other components to and from the system. Switching events may be planned or unplanned. A transmission line or other component may need to be de-energized for maintenance or for new construction, for example, adding or removing

7744-552: Was automatic, equipped with an 1100 KVA transformer, a British-Thomson-Houston 1000 kW rotary converter, switchgear, support services, and an overhead crane (designed by the Tramways Department). The substation received 11000 volts AC electricity from the New Farm Power station, via an underground feeder cable. The transformer reduced this supply, which the rotary converter then converted to 600 volts DC for

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