Track Circuits Overview and Requirements

<p>Minimum wheel base of the vehicles (A)</p> Signup and view all the answers

<p>50 mm (A)</p> Signup and view all the answers

<p>Proper drainage (A)</p> Signup and view all the answers

<p>Should be of an approved design (B)</p> Signup and view all the answers

<p>As many as possible (A)</p> Signup and view all the answers

<p>All of the above (D)</p> Signup and view all the answers

<p>Anti-creep devices (D)</p> Signup and view all the answers

<p>Wooden and concrete sleepers (A)</p> Signup and view all the answers

<p>500 ohms (C)</p> Signup and view all the answers

<p>Two rail lengths must be interposed. (A)</p> Signup and view all the answers

<p>At the entry end of the track circuits (D)</p> Signup and view all the answers

<p>Use anti-vibration devices (C)</p> Signup and view all the answers

<p>Using approved wiring diagrams (A)</p> Signup and view all the answers

<p>Red (D)</p> Signup and view all the answers

<p>235% (A)</p> Signup and view all the answers

<p>Plug-in type (9 ohm) (A)</p> Signup and view all the answers

<p>125% (D)</p> Signup and view all the answers

<p>Must be slow to pick up (D)</p> Signup and view all the answers

<p>1.5 ohm per 1000 meters (D)</p> Signup and view all the answers

<p>3 meters (A)</p> Signup and view all the answers

<p>On the outer rail in curves (D)</p> Signup and view all the answers

<p>To open the track feed and shunt the circuit (D)</p> Signup and view all the answers

<p>Compliance with permanent way requirements (C)</p> Signup and view all the answers

<p>By pressing rivets into the web of the rail (A)</p> Signup and view all the answers

<p>4.265 meters (B)</p> Signup and view all the answers

<p>Civil Engineering Department (B)</p> Signup and view all the answers

<p>It may damage nylon bushes. (D)</p> Signup and view all the answers

<p>It must be trimmed to the level of the rail table. (C)</p> Signup and view all the answers

<p>It can be reduced from 13 meters to 3 meters. (B)</p> Signup and view all the answers

<p>In the rail joint ahead of the stock rail. (B)</p> Signup and view all the answers

<p>They show no light. (C)</p> Signup and view all the answers

<p>Yellow/White (D)</p> Signup and view all the answers

<p>A red indication. (D)</p> Signup and view all the answers

<p>Type 'J' clip. (A)</p> Signup and view all the answers

<p>It should not fall below prescribed minimum values. (B)</p> Signup and view all the answers

<p>A charger or solar panel. (C)</p> Signup and view all the answers

<p>Energizing the circuit during peak usage only. (B)</p> Signup and view all the answers

<p>It must be energized to ensure shunting value stays above 0.5 ohms. (A)</p> Signup and view all the answers

<p>Approved type of secondary cells. (B)</p> Signup and view all the answers

<p>Foreign materials. (B)</p> Signup and view all the answers

<p>It should be as high as possible. (A)</p> Signup and view all the answers

<p>Railway Equipment. (A)</p> Signup and view all the answers

A closed electrical circuit installed on railway tracks to detect the presence of a train.

A track circuit used on non-RE areas that uses two rails for the circuit.

The length of the track circuit needs to be at least the maximum wheelbase of a vehicle and at least two rail lengths (26 meters).

Used to define the boundaries of a track circuit, ensuring electrical isolation between sections.

Joints placed in a way that avoid overlapping and must remain within the vehicle's wheelbase for smooth operation.

Rail ends should be square, true (flat), and free of burrs to ensure proper electrical contact.

Proper drainage is essential to prevent flooding in track circuited areas, especially in yards where watering may occur.

Ballast should be kept clean and clear of rails and fastenings to maintain proper electrical operation of the track circuit.

Special rail joints used in track circuits to create electrical insulation between sections of track.

Devices used to prevent the movement of rails, particularly at insulated joints, due to creep (movement).

Devices that detect the presence or absence of a train on a section of track by sensing the electrical signal.

Relays are located at the start of the track circuit when possible.

Safety feature in wiring to prevent damage to relays in the event of malfunctions in other stations.

Redundant systems for relay protection, providing two means of stopping power.

Sleepers used for track circuiting, having high resistance between components.

When a berthing track has multiple track circuits, it's ideal for each section to have its own indication on the control panel.

At other stations, a yellow/white light on the indicator signifies an unoccupied line, while a red light indicates an occupied line.

The limiting resistance in DC track circuits should be adjustable and meet safety standards.

Track relays are excited with a specific voltage to ensure reliable operation. The excitation range varies depending on the type of relay.

The distance before a fouling mark where a track circuit terminates to avoid vehicle interference.

Track circuit terminations should be at least 3 meters before the Fouling Mark.

Track circuits that are designed with open/closed functionalities, opening track feed during deactivation.

Avoid placing insulated rail joints on outer rails in curves to minimize dead zones triggered by a vehicle.

Resistance up to 1.5 ohms per 1000 meters of track is allowed for track circuits shorter than 700 meters.

The point where the spacing between tracks becomes less than the required minimum width. Usually used to define the boundary of a track circuit.

Lugs used in impedance bonding are fastened with rivets, using a bond press.

Inserting fish bolts by hand pressure is preferred to hammering to avoid damaging nylon bushes. Proper alignment of holes is crucial for easy insertion.

Projecting end-posts above the rail level should be trimmed before the first train passes to prevent damage and ensure smooth track transitions.

For signaled movements, the distance between the insulated block joint and the starter signal can be reduced from 13 meters to 3 meters.

Insulated block joints, detection points, and axle counters should be positioned 0 to 3 meters ahead of the starter signal.

The insulation joint in point track circuits should be located in the rail joint ahead of the stock rail joint, if possible.

Track indicators at panel interlocked stations show no light when the line is unoccupied.

When a track section is occupied, the corresponding track indicator on the panel displays a red indication, regardless of the set route.

After a train clears a track, the track indicator shows white/yellow light until the route is released. In automatic release systems it remains lit until the route is released.

The power supply for a track circuit, typically using secondary cells (batteries) and a charger/solar panel, ensuring a dedicated feed for each circuit.

Regularly checking and ensuring proper electrical connections, high ballast resistance, good insulation, and clean rail surfaces for reliable track circuit operation.

The resistance offered by the ballast under the track, which impacts the track circuit's performance and should be kept within prescribed minimum values.

Special joints in the track that electrically isolate different sections, defining track circuit boundaries and preventing current flow between them.

Excessively powering the track circuit, which can cause problems with shunting values and affect the proper detection of trains.

A measure of the change in track circuit resistance when a train occupies the circuit, indicating the presence of a train.

Track circuits are classified as RE (repetitive) and Non-RE (non-repetitive) based on their purpose, application, and wiring configurations.

The total electrical resistance in a track circuit, which depends on factors like rail length, ballast conditions, and the type of sleepers used.