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Hub AI
Stud contact system AI simulator
(@Stud contact system_simulator)
Hub AI
Stud contact system AI simulator
(@Stud contact system_simulator)
Stud contact system
The stud contact system is an obsolete ground-level power supply system for electric trams. The studs were insulating, ceramic cylinders with their tops flush with the road surface, and a conductive, cast iron contact stud located in the top of the cylinder. The cast iron stud stood about one inch (25mm) higher than the ceramic cylinder. Each stud contained a switch mechanism that made an electrical connection between the cast iron top of the stud and an underground cable when a tramcar with a strong magnet at its underside passed over it, before disconnecting when the car moved away. Electrical current was collected from the studs by a "skate" or "ski collector" under the tramcar.
Stud contact systems were implemented from 1899 to 1921, and were short-lived due to safety issues. For example, one system by Diatto had switches that contained mercury, which often leaked or adhered to the side of the stud cylinder and kept the exposed top electrified. A system by Dolter implemented switches with pivot arms, which tended to get stuck in the electrified position. Similar systems were operated by Thomson-Houston in Monaco from 1898 to 1903, by František Křižík in Prague on the King Charles Bridge from 1903 to 1908, and others such as Griffiths-Bedell, Lorain, and Robrow. Like conduit current collection systems and the modern ground-level power supply systems, stud contact systems were chosen for aesthetic reasons when overhead wire systems would be obtrusive.
Most electric railway systems take the power from an external generator. This means the electricity has to be collected while the locomotive is moving. In this context a locomotive refers to any electric vehicle on a railway track or tramway track.
Generally electric locomotives collect power through a third rail or an overhead wire. The full circuit is completed by track rails. For main line railways with their protected lines overhead lines and third rails are not a problem. Tramways operate in cities. This means that the third rail system is not really practical. It has been used, protection being offered to other road users by placing it in a central groove. Even so, the ingress of dirt and water can cause problems.
An alternative solution is to use studs. All the systems have a switch in the stud and a means to switch on the stud only while it is covered by the moving vehicle. As at least one stud must be covered by the collector at all times a long collector is used. The length has to be slightly greater than the maximum distance between any two studs. This collector is known as a skate or ski collector. This type of electrical power collector needs to move in the vertical plane to allow for natural differences in the height of the power supply studs. It is used on some full size tramway systems where there is a need for overhead wires not to be used, usually in areas of scenic value.
The stud contact system is also used on model railway systems (e.g. Märklin) as the center line of studs is less obtrusive than a single central rail. For outdoor model railway systems the use of a stud supply system with a skate/ski collector has certain practical advantages. The system is inherently self-cleaning. While the track may not be perfect, with both rails acting as the return part of the system in parallel electrical pick-up problems are substantially reduced.[page needed]
While the system was generally confined to the larger gauges (O gauge and above) the Märklin company has for many years used a version of the system (known as the Märklin system) for their HO gauge range. Peco Products make studding for their 00/H0 track range. Part nos SL-17 for track and SL-18 for turnouts.[page needed]
Modern use of the system is largely restricted to garden railways where it has the advantage of being compatible with unmodified live steam locomotives. While it is possible to insulate model live steam locomotives so that they can operate on two rail electrified track, it is difficult and trouble prone especially where the model is likely to come into contact with water.[page needed]
Stud contact system
The stud contact system is an obsolete ground-level power supply system for electric trams. The studs were insulating, ceramic cylinders with their tops flush with the road surface, and a conductive, cast iron contact stud located in the top of the cylinder. The cast iron stud stood about one inch (25mm) higher than the ceramic cylinder. Each stud contained a switch mechanism that made an electrical connection between the cast iron top of the stud and an underground cable when a tramcar with a strong magnet at its underside passed over it, before disconnecting when the car moved away. Electrical current was collected from the studs by a "skate" or "ski collector" under the tramcar.
Stud contact systems were implemented from 1899 to 1921, and were short-lived due to safety issues. For example, one system by Diatto had switches that contained mercury, which often leaked or adhered to the side of the stud cylinder and kept the exposed top electrified. A system by Dolter implemented switches with pivot arms, which tended to get stuck in the electrified position. Similar systems were operated by Thomson-Houston in Monaco from 1898 to 1903, by František Křižík in Prague on the King Charles Bridge from 1903 to 1908, and others such as Griffiths-Bedell, Lorain, and Robrow. Like conduit current collection systems and the modern ground-level power supply systems, stud contact systems were chosen for aesthetic reasons when overhead wire systems would be obtrusive.
Most electric railway systems take the power from an external generator. This means the electricity has to be collected while the locomotive is moving. In this context a locomotive refers to any electric vehicle on a railway track or tramway track.
Generally electric locomotives collect power through a third rail or an overhead wire. The full circuit is completed by track rails. For main line railways with their protected lines overhead lines and third rails are not a problem. Tramways operate in cities. This means that the third rail system is not really practical. It has been used, protection being offered to other road users by placing it in a central groove. Even so, the ingress of dirt and water can cause problems.
An alternative solution is to use studs. All the systems have a switch in the stud and a means to switch on the stud only while it is covered by the moving vehicle. As at least one stud must be covered by the collector at all times a long collector is used. The length has to be slightly greater than the maximum distance between any two studs. This collector is known as a skate or ski collector. This type of electrical power collector needs to move in the vertical plane to allow for natural differences in the height of the power supply studs. It is used on some full size tramway systems where there is a need for overhead wires not to be used, usually in areas of scenic value.
The stud contact system is also used on model railway systems (e.g. Märklin) as the center line of studs is less obtrusive than a single central rail. For outdoor model railway systems the use of a stud supply system with a skate/ski collector has certain practical advantages. The system is inherently self-cleaning. While the track may not be perfect, with both rails acting as the return part of the system in parallel electrical pick-up problems are substantially reduced.[page needed]
While the system was generally confined to the larger gauges (O gauge and above) the Märklin company has for many years used a version of the system (known as the Märklin system) for their HO gauge range. Peco Products make studding for their 00/H0 track range. Part nos SL-17 for track and SL-18 for turnouts.[page needed]
Modern use of the system is largely restricted to garden railways where it has the advantage of being compatible with unmodified live steam locomotives. While it is possible to insulate model live steam locomotives so that they can operate on two rail electrified track, it is difficult and trouble prone especially where the model is likely to come into contact with water.[page needed]