Search results
Results from the WOW.Com Content Network
In a signal box with a control panel, the levers are replaced by buttons or switches, usually appropriately positioned directly onto the track diagram. These buttons or switches are interfaced with an electrical or electronic interlocking.
A mechanical lever frame inside the signal box at Knockcroghery in Ireland Waterloo station A signalbox, LSWR (Howden, Boys' Book of Locomotives, 1907). Mechanical railway signalling installations rely on lever frames for their operation to interlock the signals, track locks [1] and points to allow the safe operation of trains in the area the signals control.
The tuned circuit often incorporates the circuit to either apply the transmitted signal to the track or recover the received signal from the other end of the section. Consider a railway with two block sections as in the diagram. Section 1 has frequency A injected at the left-hand end and received at the right-hand end.
A block section is normally the section of track from the most advanced signal controlled by the signal box in rear, and the rearmost signal controlled by the signal box in advance. Because many signal boxes are at stations, the last signal controlled by the rear box is called the starter signal , whether or not there is a station at which ...
On these lines the clearance of the controlled branch entry signal is the driver's sole authority to enter the branch, and once the train has passed that signal, the interlocking will hold it at 'danger' (and the signal cannot be cleared a subsequent time) until the branch service train, on its return journey has sequentially operated two track ...
The NX system allowed an operator looking at the diagram of a complicated junction to simply push a button on the known entrance track and another button on the desired exit track. The logic circuitry handled all the necessary actions of commanding the underlying relay interlocking to set signals and throw switches in the proper sequence, as ...
A home signal is defined as an interlocking signal at the entrance to a route or block to control trains entering that route or block. Most interlockings only have one controlled signal on each track. [1]: xii [7]: 75 Some home signals contain a third, yellow aspect, on the bottom, and are known as "call-on" signals. These signals allow the ...
The signal box can also see the lines to and from Manchester and Sandbach and all the platforms on the north side of the station. The signal box, still at its original site, is located in Crewe Heritage Centre where there are now demonstrations and simulations of the signalling in the North Junction box by a team of signallers. [2]