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conductor

 
Dictionary: con·duc·tor   (kən-dŭk'tər) pronunciation
n.
  1. One who conducts, especially:
    1. One who is in charge of a railroad train, bus, or streetcar.
    2. Music. One who directs an orchestra or other such group.
  2. Physics. A substance or medium that conducts heat, light, sound, or especially an electric charge.
  3. A lightning rod, as on a house or barn.
conductorial con'duc·to'ri·al (kŏn'dŭk-tôr'ē-əl, -tōr'-) adj.
conductorship con·duc'tor·ship' n.

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Any of various substances that allow the flow of electric current or thermal energy. A conductor is a poor insulator because it has a low resistance to such flow. Electrical conductors are used to conduct electric current, as in the metal wires of an electric circuit. Electrical conductors are usually metallic. Thermal conductors allow thermal energy to flow because they do not absorb radiant heat; they include materials such as metal and glass.

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Sci-Tech Encyclopedia: Conductor
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Metal wires, cables, rods, tubes, and bus-bars used for the purpose of carrying electric current. (The most common forms are wires, cables, and busbars.) Although any metal assembly or structure can conduct electricity, the term conductor usually refers to the component parts of the current-carrying circuit or system.

Wires employed as electrical conductors are slender rods or filaments of metal, usually soft and flexible. They may be bare or covered by some form of flexible insulating material. They are usually circular in cross section; for special purposes they may be drawn in square, rectangular, ribbon, or other shapes. Conductors may be solid or stranded, that is, built up by a helical lay or assembly of smaller solid conductors.

Insulated stranded conductors in the larger sizes are called cables. Small, flexible, insulated cables are called cords. Assemblies of two or more insulated wires or cables within a common jacket or sheath are called multiconductor cables.

Bus-bars are rigid, solid conductors and are made in various shapes, including rectangular, rods, tubes, and hollow squares. Bus-bars may be applied as single conductors, one bus-bar per phase, or as multiple conductors, two or more bus-bars per phase. The individual conductors of a multiple-conductor installation are identical.

Most wires, cables, and bus-bars are made from either copper or aluminum. Copper, of all the metals except silver, offers the least resistance to the flow of electric current. Both copper and aluminum may be bent and formed readily and have good flexibility in small sizes and in stranded constructions. Aluminum, because of its higher resistance, has less current-carrying capacity than copper for a given cross-sectional area. However, its low cost and light weight (only 30% that of the same volume of copper) permit wide use of aluminum for bus-bars, transmission lines, and large insulated-cable installations.

For overhead transmission lines where superior strength is required, special conductor constructions are used. Typical of these are aluminum conductors, steel reinforced, a composite construction of electrical-grade aluminum strands surrounding a stranded steel core. Other constructions include stranded, high-strength aluminum alloy and a composite construction of aluminum strands around a stranded high-strength aluminum alloy core.

For extra-high-voltage transmission lines, conductor size is often established by corona performance rather than current-carrying capacity. Thus special “expanded” constructions are used to provide a large circumference without excessive weight. Typical constructions use helical lays of widely spaced aluminum strands around a stranded steel core. The space between the expanding strands is filled with paper twine, and outer layers of conventional aluminum strands are applied.


Modern Science: conductor
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conductor

A material through which electric current can pass. In general, metals are good conductors. Copper or aluminum is normally used to conduct electricity in commercial and household systems. (Compare insulator.)

A material that can carry electrical current. Contrast with insulator.

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Thesaurus: conductor
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noun

    Something or someone that shows the way: director, escort, guide, lead, leader, pilot, shepherd, usher. See show/hide.

Architecture: conductor
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1. A wire, cable, or device offering low resistance to the flow of electric current.
2. A material that transmits heat readily.
3. A downspout.
4. Any vertical pipe which conveys rainwater, including one within a building.


Word Tutor: conductor
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pronunciation

IN BRIEF: One who leads or directs.

pronunciation The band members watched the conductor for their cue.

Wikipedia: Conductor (transportation)
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A train conductor

Contents

Train conductor (North America)

The conductor is the railway employee charged with the management of a freight, passenger, or various other types of train, and is also the direct supervisor of the train's "Train Crew" (brakeman, flagman, ticket collector, assistant conductor, on board service personnel). All train crew members on board the train work under his or her direction. The Conductor and Engineer, who is in charge of the locomotive(s) and any additional members of the "Engine Crew" (fireman, pilot engineer) share responsibility for the safe and efficient operation of the train and for the proper application of the railways' rules and procedures. On some railroads, Conductors are required to progress to the position of Engineer as part of union contractual agreements.

Conductors usually have the following responsibilities:

  • Jointly coordinating with the engineer and dispatcher the train's movement authority, and verifying this authority is not exceeded.
  • Communicating and coordinating with other parties concerned with the operation of the train: yardmasters, trainmasters, dispatchers, on board service personnel, etc.
  • Being alert to wayside signals, position of switches, and other conditions affecting the safe movement of the train.
  • Mechanical inspection of the rolling stock.
  • Assisting the Engineer in testing the air brakes on the train.
  • Signalling the Engineer when to start moving and when and where to stop.
  • Keeping a record or log of the journey.
  • Checking the tickets and collecting fares on passenger trains.
  • Attending to the needs of passengers.
  • On a freight train, keeping the record of the consignment notes and waybills.
  • Directing, coordinating, and usually manually performing, the shunting or switching the train needs to perform.

Passenger trains may employ one or more assistant conductors, who assist the conductor and engineer in the safe and prompt movement of the train, to share the workload, and accept delegated responsibility.

Some subway systems may employ conductors for the sole purpose of making announcements and opening/closing doors — as opposed to a train operator doing the job — for safety reasons. The conductor is often positioned in the center of the train. The New York City Subway is the largest example of such a system. The Toronto Transit Commission uses conductors as well. On some subway systems, trains no longer have conductors, and run with the train operator alone, or under One Person Train Operation (OPTO).

If a train crew's route, or tour of duty, exceeds a single shift, or is in conflict with any rules pertaining to a legal or contractual limit to the number of hours that can be worked, more than one crew may be assigned, each with its own conductor, while onboard service crew members aboard passenger trains normally remain on duty for the entire run, including their assigned meal and sleep breaks.

Since nearly the beginning of railroading in North America, on freight trains the conductor rode aboard a caboose, along with the rear flagman and the rear brakeman, and was able to perform his or her duties from there. With advances in technology and railroads seeking to reduce labor and operating costs, cabooses were made redundant and in most cases eliminated altogether. This caused the conductor to be relocated from the rear of the train to a position on the locomotive (or locomotives) at the head of the train. Gradually, these same conditions also eliminated in most cases the members of the train crew under the conductor's supervision: head and rear brakemen, flagmen, and others.

Most freight trains on most railroads today have a crew of two: one conductor and one engineer. Railroad companies continue to press for reduced operating and labor costs and this threatens to eliminate the position of conductor. Railroads rationalize that since the engineer is already qualified as a conductor he can easily assume the duties of a conductor. In fact, the progression on most railroads are that engineers begin their career as a brakeman/asst. conductor, conductor and finally engineer. Some railroads, have already implemented such a strategy, notably the Montana Rail Link, and operate with an Engineer, and an "Assistant Engineer". However, most railroads are contractually obligated to employ at least one conductor in addition to the engineer, via Crew Consist Agreements negotiated with the major rail unions, primarily the United Transportation Union (UTU). Therefore, in order to eliminate the conductor position it would be necessary for the railroads and unions to negotiate on this issue. If the railroads were successful, the conductors that have already been trained and certified as engineers would be able to work as engineers. Those that have not yet progressed to engineer would have to be trained as engineers as positions become available. Others would have to accept other positions or possibly lose their jobs. The primary union for engineers, the Brotherhood of Locomotive Engineers does not support this movement, claiming that requiring its members to operate trains alone would be unsafe. The conductors' union, the United Transportation Union, also opposes this initiative, despite historical differences with the engineers' union.

Train guard (United Kingdom and Australasia)

In the UK and Australia/New Zealand, the person with ultimate responsibility for operation of a train is usually described as the guard. The term "guard" is derived from the days of stagecoaches.

Until the latter part of the 20th century, guards on passenger trains in these countries did not have routine responsibilities for ticket inspection or sale. Their jobs focused more on safe operation of their trains, timekeeping, handling parcels and other consignments. In recent years, passenger train guards have been assigned more responsibility for on-train revenue collection and ticket inspection. Under British Railways, there were several grades of guard, depending on whether the guard worked on freight or passenger trains and there was also a purely operational Guard grade that worked freight and passenger trains but without customer contact. When the Guard has a significant customer contact role, the position is usually classified as Conductor-Guard or Conductor. Since British Rail, there has been a number of titles for a Guard's grade but with a few exceptions all now carry out some sort of customer facing role.

On long-distance expresses, the Conductor's title is sometimes enhanced to Senior Conductor in line with the implied prestige of operating these trains and historically under British Rail the long distance InterCity trains were normally worked by the most senior guards at the depot, hence the name Senior Conductor. Several of the more recent private passenger train operators in the UK have further renamed the (Senior) Conductor's passenger facing title to "Train Manager", although in the Rail Safety Standards Board (RSSB) Rule Book they are still referred to simply as the Guard.

Today

In Australia and New Zealand, most inner city commuter rail networks are now operated by only a Driver. There is still the presence of a Conductor on some of the more long distance services, such as on V Line in the state of Victoria. In Australia's largest city, Sydney, all suburban and intercity trains operate with a Driver and a Guard. The Guard is responsible for the safe operation of the train (in co-operation with the Driver) in accordance with the timetable. The Guard is primarily responsible for railway safeworking duties but also has a limited customer assistance role. Sydney Train Guards are not responsible for revenue or policing duties on trains as these roles are carried out by NSW Transit Officers.

In the United Kingdom, with technological improvements and to reduce cost, some trains have lost their Guards and became Driver Only Operated (DOO). British Rail was the first to bring this in on some commuter services in London and Glasgow, as well as almost all non-passenger trains. In 2003 a very controversial amendment was made to the operational rule book of the UK, removing part of the safety and operational role of the Guard to the Driver. Privatisation saw Train Operating Companies (TOC) attempt to bring in DOO to other areas of the network; c2c operating from London Fenchurch Street is an example of this. Pressure after several fatal train crashes has reversed this trend for now to the point some TOCs have restored Guards to services that were stripped of them, First Great Western did this to certain services it acquired when it took over the operation of Thames Trains. Currently there are several different titles used to describe a Guard; Train Manager, Train Host, Conductor and South West Trains still uses the term ‘Guard’. The role of the guard is set out by a mixture of the Railway Rule Book and Train Operating Companies.

As well as ticketing and customer care, Guards must be trained in "emergency protection" duties, should an emergency arise, along with other operational rules. This involves using emergency kit such as detonators, track circuit clips and flags to prevent other trains colliding with, for example a derailed train. If in a crash the driver became incapacitated, the Guard is the only person left who can protect the train. More day-to-day duties include operating the Public Address system and the train doors.

Conductors/guards in Europe

A Russian train conductor in front of the express train "Repin"

Switzerland

In general, Conductors in Switzerland have the duty of collecting tickets and punching them, fining people the first charge of 80 CHF for not having a valid fare (tickets in Switzerland are valid for one month), to make announcements on the public address system. They also may fine passengers if they take a longer trip than normal. For example, if one takes a train to Bern via Biel, having departed from Geneva; which is a longer trip than taking the InterCity via Lausanne, the conductor can fine the passenger a supplementary fare. They sound a warning when the train's doors are going to close. Many conductors, especially those on night shift and on isolated regional lines, are being trained in self-defence against would-be assailants.

Railway guards in Asia

Guards are posted on all passenger trains and goods trains in India and no train shall move ahead without a guard on the train. The passenger train guard generally called as "Mail Guard" is completely responsible for the train, its schedule, the passengers and their safety including the driver. These guards have a specific uniform(Generally white) and belongings to carry on, before they can actually depart the trains for long journeys.

During the day, the guards still use the traditional green flag to signal the driver to depart and the red flag to stop; along with the Motorola Walkie Talkie two way radios. The flag is replaced with the lamp signals after the sunset. Before signalling the departure, a whistle is blown by the guard at least couple minutes before, as a warning to the passengers to quickly board the train. After ensuring that all passengers are safe to travel, the guard signals the green flag by waving the same out from his Brake Van door. In case of emergency, the red flag is flagged to the driver to indicate a stop; emergency brakes may also be applied by the guard to stop the train to a complete halt. In no case the driver shall move the train without a signal from the guard, indicating the guard is "in charge" of the train.

Passenger guards also accept heavy parcels and luggage boxes, those which cannot be carried in by passengers in passenger coaches. Some fast moving perishable goods like vegetables, milk are also transported under the supervision of the guard and he is responsible for proper loading and unloading of the same at various destinations mentioned on them.

Maintaining the passenger train on schedule is very important function of the guard, keeping in mind the passenger safety too. The guards have to carry a first aid box with their belongings along with other important items, all in a medium sized duty box(generally painted black in color) made of tin. The name, designation and base location of the guard are printed/painted in white on the box.

Rarely do the guards issue tickets or collect fares in India; they do when a train halt does not house a ticketing window. In this case, the cash needs to be maintained by the guard and surrendered at the destination. A designated passenger train, halting at all stations carries a very large and heavy cast iron "cash safe" in the guard's brake van, where daily ticket sales cash is deposited in a leather pouch by the Station Manager(earlier called the Station Master in India).

Since the late 1990s, all guards are provided with Motorola Walkie-Talkie/Two-way radio so that they can communicate with the driver, the trains passing in opposite direction, if required. The Walkie Talkie is yet to replace the traditional Red and Green Flags. Green and red flags and the green and red lamps signalling in India could get abandoned in future as lengths of the trains will get longer, making the flags and lamps invisible to the engine driver.

Tram (streetcar) conductor

Many antique or heritage trams (streetcars), which operated through the earlier part of the 20th Century, were designed for operation by a crew of two or more. The conductor primarily collected fares and signaled the driver when safe to depart from stopping places. The conductor also assisted with shunting when necessary, changing the trolley pole and attended to passengers' needs.

Modern vehicle design and ticketing arrangements have largely done away with the need for conductors on street railways and Light Rail systems. However in recent years a number of modern tram or Light Rail systems have introduced (or re-introduced) conductors to minimise fare evasion and to provide customer care, supervision and security functions, even in situations where a second crew member is not strictly needed on account of the vehicle design or operation.

In Britain, The Midland Metro and Sheffield Supertram modern Light Rail systems have both started using conductors due to problems with ticket machine reliability. Nottingham Express Transit started with conductors. Manchester Metrolink and Croydon Tramlink both rely on ticket machines at stops.

Systems of ticket checking and selling by a conductor:

  • takes place while entering, the vehicle cannot leave until this is (almost) finished
  • takes place after entering an entrance lobby, while the vehicle already moves, after which the passenger moves to the seating area of the car
  • the passengers get seated and the conductor comes to them

Modern mass transit systems which operate with conductors on trams include:-

System Location
Glenelg Tram Adelaide, Australia.
GVB Amsterdam Amsterdam, The Netherlands.
Midland Metro Birmingham / Wolverhampton, UK.
Blackpool tramway Blackpool, UK - on pre-World War II vehicles.
Nottingham Express Transit Nottingham, UK.
RET Rotterdam, The Netherlands.
Sheffield Supertram Sheffield, UK.
Metro Light Rail Sydney, Australia.

Bus conductor

Traditional British open-platform Routemaster bus, operated with a conductor.

Up until the 1970s and into the early 1980s, conductors, or "clippies", were a common feature of many local bus services in larger towns and cities in the UK and Ireland. Conductors were portrayed in the British TV series, On The Buses.

The main reason why two-person crews were needed was that most towns and cities used double-deck vehicles for their urban bus services and until the 1960s, all double deck vehicles were built with front-mounted engines and a "half-cab" design, like the familiar Routemaster London bus. This layout totally separated the driver from the passenger saloons. The conductor would communicate with the driver using a series of bell codes, such as two bells to start (the well-known "ding-ding").

Many of the half-cab double-deckers were boarded from an open platform at the rear, while other buses were equipped with a forward entrance and staircase and automatic doors operated by the driver. In each case a conductor was needed to collect fares and, especially on the rear-entrance design, supervise passenger loading and unloading. In some places, in the late 1960s and early 1970s, there were experiments with later forward entrance half-cab double-deckers to remove the conductor and have the driver in charge of selling tickets as on the rear entrance buses that were common by that time, therefore giving the benefits of one person operation without the cost of replacing vehicles that still had some years life left in them. These were unsuccessful, though, since the driver was required to turn around to deal with passengers, usually through a small opening between the driver's and passenger compartments, and this idea was soon scrapped and the buses reverted to conventional conductor operation.

In the late 1950s, new designs of higher-capacity double-decker buses began to be introduced with the engine compartment at the rear of the vehicle and the entrance directly adjacent to the driver. From July 1966, UK transport regulations were changed to allow operation of urban double-deck buses by the driver only, who could now take responsibility for fare collection as well as supervise all passenger loading and unloading.

In some countries, seated conductors were introduced in the post-war decades. On this double-decker bus which operated in Vienna, Austria from the early 1960s, passengers were obliged to board the vehicle at the rear, pass the conductor and alight through the middle or front entrances.

The new designs of rear-engined buses and so-called "one person operation" were adopted quickly by some municipal operators, more slowly by others. New half-cab buses continued to be ordered by the more conservative municipal operators through the 1960s, but manufacture of this type of vehicle for the UK market had ceased by about 1970. This was accelerated by a UK Government grant which supported the purchase of "one person operated" vehicles, but was not available for purchase of traditional half-cab buses.

Through the 1970s the proportion of urban bus routes operated with conductors declined, as older vehicles were steadily replaced with new buses equipped for one-person-operation, and operators grappled with staff shortages, rapidly increasing costs and falling ridership. By the early 1980s bus conductors were largely obsolete in all cities except London and Dublin.

London was a special case, with two-person crews continuing to operate a number of bus routes in central London until late 2005, well beyond their demise in the rest of the country. This reprieve for conductors was due to continued use of the famous Routemaster bus.

The Routemaster had been purpose-built for London conditions and continued to be very well suited to the busiest routes in the most congested parts of central London. This was because of its maneuverability, fast passenger loading/unloading capability and fare collection by the conductor instead of the driver. The construction of the Routemaster vehicles was of high-quality, the design robust and the mechanical and body parts could be easily re-built and refurbished, which all greatly improved the vehicle's durability. Importantly, the "traditional red bus" is also a unique tourism icon for London, instantly recognisable around the world.

Although the majority of bus services in the London metropolis (and all routes outside the central area) have been operated by modern driver-only vehicles since the late 1980s, 20 regular routes retained Routemasters and conductors in 2003. Between 2003 and 2005, each of these has been progressively converted to modern vehicles and one-person-operation. The process was largely driven by a political agenda[neutrality disputed] on disability-accessibility, and assisted to some extent by the increase in litigious passengers claiming injuries due to the Routemaster's open rear platform. There were also increasingly frequent robberies and attacks on conductors, who could find themselves working in an isolated and vulnerable environment.

The last "regular" (as opposed to tourist-oriented) Routemaster-operated service was the 159 from Marble Arch to Streatham. Conductor operation finally ceased on the 159 on 9 December 2005.

See also


Translations: Conductor
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Dansk (Danish)
n. - leder, konduktør, togfører, lynafleder, guide, chef, nedløbsrør

Nederlands (Dutch)
dirigent, geleider, conducteur, gids, bliksemafleider, manager/ directeur

Français (French)
n. - (Mus) chef d'orchestre, (Transp) receveur, (Rail) chef de train, (Élec, Phys) conducteur

Deutsch (German)
n. - Dirigent, Leiter, Schaffner

Ελληνική (Greek)
n. - οδηγός, εισπράκτορας (λεωφορείου κ.λπ.), (μουσ.) διευθυντής ορχήστρας, μαέστρος, (ηλεκτρικός) αγωγός

Italiano (Italian)
direttore d'orchestra, conduttore, bigliettaio, controllore

Português (Portuguese)
n. - condutor (m) (de bonde, trem), condutor (m) (Eletr.), maestro (m) (Mús.)

idioms:

  • lightning conductor    condutor (m) de iluminação

Русский (Russian)
дирижер, проводник

idioms:

  • lightning conductor    молниеотвод

Español (Spanish)
n. - director de orquesta, conductor, revisor, cobrador

Svenska (Swedish)
n. - ledare, dirigent, konduktör, stuprör (am.)

中文(简体)(Chinese (Simplified))
领导者, 向导, 管理人, 指挥

中文(繁體)(Chinese (Traditional))
n. - 領導者, 嚮導, 管理人, 指揮

한국어 (Korean)
n. - 지도자, 지휘자, 도체

日本語 (Japanese)
n. - 指導者, 案内者, 指揮者, 伝導体, 避雷針, 車掌

العربيه (Arabic)
‏(الاسم) موصل, قائد فرقه موسيقيه, جابي حافله نقل الركاب‏

עברית (Hebrew)
n. - ‮מנצח תזמורת, מוליך חום או חשמל, כרטיסן, מדריך אן מנהיג‬


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