Railway Signals in Goyanes

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A modern 5-light signal displaying the "High Speed Clear" aspect. This allows the train to proceed above 130 km/h following cab speed signals.

Railway signals in Goyanes evolved from electro-mechanical semaphores that changed position to indicate track block status. Before then though, railways employed “track officers” to manage sections of track using hand gestures, line-of-sight techniques, and physical tokens that had to be passed from train to officer and vice versa. This was wildly inefficient, and as the railways grew, technologies were developed to reduce collisions and improve railway safety. Starting with the Grand Trunk Railway and spreading quickly around the nation, electric track circuits that controlled semaphore signals began to take hold. The process started in the 1870s, but by the 1890s, Goyanes’ railway network was fully electro-mechanically signaled.

In 1885, the Stortoghass Tunnel Crash in Gojannesstad occurred, where a through train engineer running a service from the Hysende-Osanhalt-Kongsland Railway onto the grand trunk in Gojannesstad became confused by the Grand Trunk's signal system, and crashed the train, resulting in 30 deaths and more than 50 injuries. This caused the Ministry of Transportation (then known as the Ministry of Railways) to mandate a new, unified, national signal system. The new signal system became known as M-Class signals (M-klassesignalen). M-Class signals used semaphores and relays, and a unified set of meanings. This helped promote inter-operation, and created a stanrdized and safer working environment for the railways.

By the early 1930s, the Ministry of Railways had consolidated all of Goyanes' railways into four companies, the Grand Trunk, the Hysende-Osanhalt-Kongsland, the Nordstrom Seabord, and the Hirendag Road. However in 1921 a fatal accident caused the Ministry of Railways to mandate the four lines to install train protection systems. The system invented by the Grand Trunk Railway and Nasjonalsignalen, ATB, became the most popular, as it provided full cab signalling, and beginning in 1930, was installed on main lines in Goyanes. As color-light signals began to see widespread use during the consolidation era, the system was standardized to fit the ATB system and provide complete unification of teh stafety ststem.

The devolopment of the HHT system in the 1960s and 1970s forced Gojan Jårnbaner, Goyanes' state railway operator, to develop a new cab signalling system. The high speeds of the HHT system prevented operators from being able to see and comprehend any trackside signals, so a system that transmits not just speed like ATB, but track information directly to the driver was created, known as AVK. AVK is currently on its second iteration. In addition, a new system known as ATS-V that uses train-mounted electronics and track-mounted transponders to enforce red signals, confirm yellow and double yellow signals, and stop a train if it is running too fast before a red signal. ATS-V is installed on all classic lines in Goyanes.

Currently in Goyanes, all signals are cab-only or color-light, all classic lines and trains are equipped with ATS-V, and high-speed trains and lines are equipped with AVK.

Fixed Signals

Signals in Goyanes use a combination of route and speed signalling that has evolved over time from the previous semaphore system.

Main Signals

Main signals (Hovedsignalen) are called so because they protect a section of track, known as a block. The main signal protects the entrance to the block of track is guards. There are three types of main signal in Goyanes, starting signals, home signals, and block signals. These three types of signals are governed by two different regimen of signalling practice, automatic block signals and non-automatic block. Automatic block means the block is protected by a simple circuit that detetcts a train inside a block and automatically changes aspcects to block access to that section. When the train leaves the block, the block is automatically opened up again. Non-automatic block means that signals must be lined up by a dispatcher manually ahead of time. Typically interlockings are protected by non-automatic block signals and sections between interlockings are protected by automatic block signals. However, under the non-automatic block system a starting signal has no protected section; it only indicates that all turnouts on the route to the mainline are switched correctly. Under the non-automatic block system trains cannot leave a station without an appropriate token, even if the starting signal is clear. This token is usually a separate light that activates when the stationmaster who controls that block allows the train to pass through the interlocking.

All main signals in Goyanes have between two and six lights, that are either red, yellow, or green. Two-bulb signals may have either green or yellow, but must have red.

The following graphics show main signals. In addition, the main signals shown have the capability of displaying all aspects. In most circumstances, main signals can only display certain aspects that relate to the condition of the lines they protect, and as such could have as few as two lamps, instead of the five pictured here. A note, 5-bulb signals cannot display both high speed clear and restricted aspects. However, 6-bulb signals can display all aspects, in which case the green lamp occupies the top slot. Regardless, the light and color combinations carry the meaning, not the total amount of bulbs on the signalhead.

Aspect	Name	Description
	High Speed Clear (Hastiket Vortsette)	The high speed clear aspect is used on certain lines when trains become authorized to travel over 130 km/h. It is also interlocked with other signals so that there are at least three clear blocks ahead, unlike the usual two that a normal clear signal provides.
	Clear (Vortsette)	Proceed at the maximum authorized track speed, or 130 km/h if the track speed limit is higher. There are at least two clear blocks ahead.
	Reduction (Verminsken)	The aspect is flashing. It is used to indicate a speed limit of 100 km/h, usually to slow trains down from high speed. There are at least two blocks clear ahead.
	Limited (Begrenset)	Displayed when the next signal displays restricted speed (YY) (or caution (Y), in the case of a short block section or poor visbility of the next signal). The speed limit is 60 km/h. There are at least two clear blocks ahead.
	Caution (Advarsel)	Displayed when the next signal displays stop. The speed limit is 40 km/h. Sometimes the block ahead maynot be displaying stop if the block clears up, but the driver should never expect anything better than stop.
	Restricted (Smal)	Displayed when the distance to the next signal is unusually short, another train is running in advance of the signal or the safety overlap at the next signal is shorter than normal. The speed limit is typically 30 kmh.
	Stop (Stanna)	Not to be passed. If it is an automatic block signal, non-blocking operation is allowed, where train can continue at a maximum speed of 15 kmh after approval from the dispatcher.

If a signal lamp burns out, it will automatically switch to the stop aspect. A signal with all lights shut off should be treated as a stop sign unless there is a decomissioning sleeve on the signal, an "X" shaped board on the signal, or if it is turned to the side to face away from the tracks. Additionally, GJ mandates at least two bulbs be off between on bulbs, which is why there ends up being multiple yellow bulbs when there's ore than three bulbs on a signal.

Home Signals

Home signals (Hussignalen) permit trains to enter the station or interlocking. A home signal is absolute; therefore, non-blocking operation is always prohibited. Some stations have multiple home signals, due to station layout. In these cases, each home signal has an identification number which is counted from the outside of the station. In high-traffic areas, some operators install home signals in the center of a platform track to divide the block section. Some operators treat such signals as block signals. In non-interlocking stations, there may be a No.0 block signal instead. Home signals protecting stations usually have a "TH" plate under the signal, and those protecting interlockings usually have a "KREUSS" plate under the signal.

Starting Signals

A starting signal (Utgangsignalen) permits trains to depart the station, and is an absolute signal. In some stations, there are multiple starting signals due to station layout. In such cases, each starting signal has an ID number which is usually the same as the track number. In non-interlocking stations, there may be a block signal instead of a starting signal.

Block Signals

A block signal (kreissignalen) begins a block section in an automatic-block system. In non-blocking operation a train can proceed past a block signal after stopping for one minute at the signal and contacting teh dispatcher, even if the signal is "stop".

Each block signal is identified by an identification number; as a train travels to the next station or interlocking, the ID numbers count down. The last block signal before the home signal is number one. Each signal is associated with the next one; therefore, it cannot be manipulated by dispatchers or signalmen, unless there is a computerized central traffic system such as in Gojannestad or Naderfjord (ATN). The signal display depends on the presence of a train in advance of the signal and the display of the next signal.

A block signal is a permissive signal, so non-blocking operation is allowed. A train can continue at a maximum speed of 15 km/h after stopping for one minute and contacting dispatch before a block signal displaying stop. The train must not increase speed over 15 km/h until it arrives at the next main signal. Some lines do not require a dispatcher to be alerted before proceeding past a block signal displaying stop, if they have waited for a full minute.

A No. 0 block signal at the platform of Grønmark Station in Gojannesstad displaying the "limited" aspect.

At crowded stations on high-traffic lines, a platform track may be divided into two block sections so a following train can enter the track soon after the preceding train has departed. This signal is known as a No. 0 block signal. GJ treats this signal as a part of its home signals. At non-interlocking stations of GJ, the last block signal before the station is treated as a No. 0 block signal and known as the "home equivalent block signal." This signal is not absolute, since (unlike home signals) non-blocking operation is permitted. On ATN (Automated Train Operation Network) lines in Gojannesstad and other major urban areas, block signals are numbered serially, regardless of non-interlocking stations. In this case, some block signals are defined as home-signal equivalent or starting-signal equivalent using the corresponding plate below the signal.

Call-On Signals

Normally, only one train can enter a block section for safety; however, with this rule a train cannot be coupled with another train. A call-on signal (Spesiellingangsignalen) permits a train to enter a section already occupied by another train to enable coupling.

A home signal protecting a station with a shunting signal underneath the main signal displaying stop. The single bulb under the main signal is for route signalling.

A call-on signal is installed under a home or shunting signal. The train guided by a call-on signal can proceed under 15 km/h (30 km/h if instructed bt ATB) until it reaches the next train train. In stations where two trains use the same track simultaneously, call-on signals are required to allow two trains on a single block section. However, this is unnecessary if the platform track is divided into two block sections as discussed previously.

When calling-on is allowed, the white lights are activated diagonally. When calling-on is not allowed, the white lights are horizontal.

Shunting/Dwarf Signals

Shunting signals, also known as “dwarf signals” (kleinesignalen), are used for shunting purposes in yards. They are smaller in size, and use only white aspect colors. They may be placed on top of a half-height post, or placed at the same height as the trackbed.

Signal		Meaning
	Danger	The signal must not be passed without radio permission from dispatch.
	Movement Allowed	Movement is allowed. All points and derailers have been set. The track ahead is clear. Speed limit 30 km/h. This aspect is commonly used to allow permittivity of a signal at danger.
	Movement Allowed with Caution	Movement is allowed Points and derailers are in the right position. The track is not clear however. Speed limit 20 km/h. This aspect is commonly used to allow permittivity of a signal at danger, specifically to couple/shunt trains already in a platform or a siding track. The train must come to a complete stop before continuing.
	Movement Allowed Check State	Movement is allowed All points and derailers may not have been set. Driver must ensure all points are set as well as clearance ahead. This aspect is used to grant entrance into yards with manual track points and no electronic control.

Railroad Crossing Status (RCS) Signals

A main RCS signal displaying "Crossing Not Secured/Danger"

RCS signals (Vagersignalen or VS) are used to indicate to the driver the status of a railroad crossing ahead on the line. Various factors affect the aspect displayed. The most simple kinds simply confer if the gates are closed and locked, but the most advanced types rely on sensors that can detect if vehicles are stalled on the crossing, in addition to detecting whether or not they have been locked. There are two types of RCS signals, just like color-lights, they are Main Signals and Distant Signals. Main RCS signals are identified by a “V” sign under the bulbs. Distant RCS signals are identified by their shape and unique bulb layout.

A related signal called a Bridge Status Signal (Bryggesignalen or BS) uses the same signalheads and aspects, except the main BSS signals have a "B" signpost under the signal head, similar to how main RCS signals have a "V" signal on them.

Main RCS Signals (Hovedvagersignalen/HVS)

Signal		Meaning
	Crossing Not Secured Danger	The crossing is not secured, the train must attempt to stop before the crossing. Emergency brake application is acceptable.
	Crossing Secured Proceed	The crossing is secured, proceed normally.

Distant RCS Signals (Vørvagersignalen/VVS)

Signal		Meaning
	Expect Crossing Not Secured (Crossing not clear)	The Main RCS signal is at danger, the driver must slow the train down immediately and attempt to stop before the crossing. Emergency brake application is acceptable.
	Expect Crossing Secured (Crossing clear)	The Main RCS signal is showing secured, proceed normally.

AVK System

The orange sign indicating a non-permissive track block. On the opposite track an E2 series HHT train is entering the station area at Orkanger, Nyhett.

The AVK system was invented in 1959 and inplemented in 1964 for use on HHT high-speed services, as operators would not be able to read and interpret lineside signals at high speed. AVK-1 was the first iteration of the system invented, with the second and current iteration being known as AVK-2. Signaling information is instead transmitted to the train and displayed as part of the train controls. The driver is shown the safe operating speed, displayed in kilometers per hour. The late-1990s-developed AVK-2 system transmits more information than traditional signalling would allow, including gradient profiles and information about the state of signaling blocks much further ahead. This high degree of automation does not remove the train from driver control, although there are safety mechanisms that can safely bring the train to a stop in the event of driver error or incapacitation.

History

The AVK system was developed by Gojan Jårnbaner engineers in conjunction with the Nasjonalsignalen company, which currently markets the system worldwide. The system was based off of ATB, a proven system that has been installed on conventional lines since the 1930s. The AVK-1 system went online in the first section of the HHT system to open, the Gojannnesstad-Naderfjord high-speed railway.

AVK-1 was a relay-based system that used rigid blocks, and communicated with the train using pulse codes sent to the train based on the signal state. The pulse codes are sent theough the front axle of the train as it bridges the circuit across the two rails, and the pulse code is interpreted by a sensor on the train, which otputs a maximum permitted speed based on the track limits and the block status ahead. In this aspect it is extremely siilar to ATB. However, as the train slowed down, the rigid block system caused an uncomfortable braking experience, which required lowering speed, then easing off the brakes, then braking harder again. This, among other things, prompted the development of AVK-2.

By 1999, the engineers decided to improve the AVK system with new microprocessors both onboard and trackside, and a new, more computerized trackside system. The new system was called AVK-2. AVK-2 was marketed by Eindrisson engineers as part of a multi-tiered approach. AVK-2 would be standard operation (cab signalling and automatic train protection from overspeed and stop signals), AVK-2.1 (optional automatic train control), and AVK-2.2 (fully automatic operation).

In 2010, the AVK system was applied on certain classic lines to test throughput capacity. It proved successful and now, certain very-high capacity lines have had the AVK-2 system installed to increase frequency of trains.

Implementation

In AVK-2, the track is dotted with transponders mounted in the center of the track every usually 200m to 1 km (in some schenarios they can be as close as 10 meters, such as at where a side track joins a main line). The sections of track block are guarded by transponders at both ends, but there are usually transponders inside the track block as well. The track block uses a standard track circuit to detect the position of a train. Lineside equipment stations transmit the last updated distance to the next train to the train via the transponder, as well as the maximum permitted line speed.

An old-style transponder coil located along the platform at Ingolfur Station. These models are compatible with the new ones, but are being replaced.

There is a main equipment box that controls about 10 blocks, which in turn is controlled by the central control room for that line. The central control room is able to integrate the AVK-2 system with the scheduling system to maintain precise headways, and ensure safety of operations.

Onboard the train, as it passes over a transponder, the distance to the train ahead, maximum line speed, and track gradients are recieved, and this information is sent to the onboard computer, which determines a braking curve using the given information and known information such as train acceleration and braking performance. The computer then displays an authorized speed on the dashboard. The authorized speed is constantly being recalculated, as the train estimates its position to the train ahead, and along the line (for gradient purposes) using the onboard odometer. The distance is confirmed/reset every kilometer when the train passes over a transponder, which subsequently updates the train on its current position.

When the train reaches the point where the computer determines it should begin braking, or if it passes a transponder and an updated speed is given, an alarm sounds in the cab which the operator must confirm. Then the braking curve begins. The operator should brake normally, but keep an eye on the speedomoeter, as the speed limit decreases in real time. If the speed of the train exceeds the maximum authorized speed, either while cruising or braking, the train will apply brakes to bring it below the authorized speed. The continuously dynamic braking curve drastically improves passenger comfort, and allows for closer headways. Once the authorized speed stops decreasing, a bell sounds in the cab.

A lineside equipment station on the Nyhett Valley High Speed Line. An new-style AVK transponder is visible in the lower right in the track.

The signalling system is permissive; the driver of a train is permitted to proceed into an occupied block section without first obtaining authorisation. An occupied block section is indicated on the speedometer by a speed limit of 30 km/h. When the speed limit is 30 km/h, the train cannot exceed 32 km/h, and must stop before any obstructions, track defects, or trains ahead. Non-permissive blocks, such as at entrances and exits to stations, and at interlockings, are marked with an orange, diamond-shaped, board with a black cross. There will always be a transponder protecting the block, as well as a dwarf signal. If a driver encounters a non-permissive board, they must do two things. First, they must check the speed indication. If it is not 30 kmh, they may proceed as normal. If 30 km/h is given, they must look at the dwarf signal at the non permissive sign, if it displays stop, they must stop before the board, and if it displays proceed or proceed with caution, they can pass the board. Entering a non-permissive block at danger will trigger an emergency brake application. Non-permissive blocks can also be guarded by a single color-light, as is the case on newer tracks. If the section is protected, a red light will illuminate. GJ has been swapping the dwarf signals for color lights since 2010 as they offer improved visibility.

A dwarf signal protecting a non-permissive track section. The light above the dwarf signal is the new color-light which has replaced the dwarf signal.

The additional information passed along by the transponders can concern a variety of events or actions, such as signal system changes at the entry or exit of a high-speed line, arming or disarming the AVK-2 system, closing air vents before entering a tunnel at speed, raising and lowering the pantographs, or changing the supply voltage at system barriers. When trains enter or leave the high-speed line from classic lines, they pass over a ground circuit which automatically switches the driver's dashboard indicators to the appropriate signalling system. For example, a train leaving the high-speed line onto a classic line would have its AVK signalling system deactivated and its traditional ATS (automatic train stop) and HBK (automatic speed control) systems activated by the train's onboard computer at the boundary point.

Oversight

A "black box" similar to an aircraft flight data recorder, passively watches over the entire process, monitoring a variety of parameters and recording the events onboard the train. In AVK-2-equipped trainsets, older paper-strip recording equipment has been replaced by a digital recording system. Every action taken by the driver (throttle, brakes, pantographs, etc) as well as signalling aspects (for AVK-2, and conventional signals (via the ATS and HBK signals) are recorded on magnetic tape for later analysis using a desktop computer.

Another system, known as FK, oversees the driver's alertness. The FK system is located in the brake handle. The handle itself is a button, and when the handle is pressed down, the train can operate. The FK system asks the driver to release and depress the brake handle every 60 seconds if there has been no input to the train's controls. The timer resets every time there is an action. If the handle is released, there is a grace period of about 15 seconds before an alarm sounds. If the alarm sounds for 10 seconds, the emergency brakes are applied.

A small amount of overspeed allowance is allowed before the AVK system will activate the emergency brakes. For 30 km/h the tolerance is 2 km/h. Below 80 km/h, the tolerance is 5 km/h. Between 80 km/h and 160 km/h it is 10 km/h. At speeds in excess of 160 km/h, it is 15 km/h. If the speed is in the tolerance speed, an overspeed warning buzzer sounds, and is not deactivated until the speed goes below the limit speed again. If the speed exceeds the safety tolerance the buzzer switches to an alarm and the brakes apply to bring the speed within the tolerance. If the driver does not aknowledge the alarm and safety braking after 5 seconds of braking, the emergency brakes will activate and the train will be stopped. The alarm does not switch off until the train comes to a complete stop.

Cab Display

In the centre of the driver's desk in an HHT cab, or on any other AVK-equipped train, just below the windscreen, there is the speedometer. The permitted speed is showed in a bar over the actual speed, as well as on a numerical readout next to the speedometer. As the braking curve is enforced, the speed limit bar decreases in real time, allowing the driver to adjust his braking rate accordingly. All the in-cab signalling displays must be very reliable, since they are critical to safety. The coded software is safety-critical, and enforces that the current aspect being displayed to the driver is correct. If there is a failure in the display unit, appropriate action is taken to stop the train.

The speedometer aboard an E5 series HHT train. The blue bar represents the AVK-permitted speed, the green bar represents the actual speed. A numerical display provides a backup readout, partially visible to the right of the screen.

AVK-2 has extensive redundancy built into it, and one might wonder why it is not used to control the train directly. However, keeping in mind the lack of adaptability of the system to unexpected situations, it is considered desirable to retain a human in the loop. Driving an HHT is therefore done entirely manually, but the signalling system keeps a very close watch to ensure maximum safety.

Automatic Train Stop (ATS)

Automatic Train Stop (Automatisk Togstanna/ATS) is a system that governs color-light signals that are displaying a stop aspect, or any sort of cautionary aspect. The current ATS system (ATS-M) was invented at the same time as the L-Class signal system. Previous ATS systems relied on mechanical infrastructure, such as tripcocks opening brake valves when a signal was passed at danger. Such systems still exist on select railways, such as the Gojannesstad U-Baner, among others. However, on the GJ network, the ATS-M system is operational.

A legacy ATS system that uses a tripcock on the Naderfjord U-baner. The tripcock is armed on the left and disarmed on the right.

The ATS-M trackside reciever in the center of the rails and the trackside transmitter on the outside of the rails.

ATS-M functions using both trainside and trackside infrastructure. Trainside, there is an electromagnetic impulse transmitter located under the leading car or locomotive, along the centerline, and an electromagnetic impulse reciever that hangs on the right side (in the direction of travel), offset several centimeters from the edge of the rail, and connected to an alarm and pushbutton in the cab, as well as the power and brake system. On some locomotives/multiple unit cars there may be two recievers (one on each side). If so, before departure a switch is set in the cab to indicate which reciever should be used (standard practice is to use the right-side reciever). Trackside, there is a reciever lined in the center of the track (underneath where the train's transmitter would pass) which is connected to a transmitter on the outside of the rail (underneath where the train's reciever passes).

The ATS-M trainside transmitter under the center of the locomotive and the trainside reciever on the side of the locomotive.

When the train's electrical system is on (required for it to move), the transmitter is constantly sending positive electromagnetic pulses. This interacts with the ATS-M array at a signal as it passes over it. When a signal is displaying a clear aspect, the ATS-M array disconnects the track's reciever from the track's transmitter. Therefore, as the train passes the signal, there is no interaction, so the train proceeds as normal.

The ATS-M console in the cabin of a train. The light/confirmation button is in the center, and is turned to aknowledge. The ovveride switch is labeled "M" on the right side for "manual."

When the signal displays caution, the trackside arrays connect, and a polarizing circuit connects, so when the train passes over the array, the reciever picks up the positive impulse, and transmits a positive impulse back via the side transmitter. The train reads the positive impulse through its side receiver, which triggers a buzzer in the cab and activates a caution light which stays on until the confirmation button is pressed. If the confirmation button is not pressed after 5 seconds, the emergency brakes activate and the power is cut off.

When the signal is displaying a stop aspect, the the trackside arrays connect, however the polarizing circuit does not connect, so when the train passes over the array, the reciever picks up the positive impulse from the train, and transmits a negative impulse. The train reads the negative impulse on its reciever, which triggers automatically the emergency brakes and cuts all power systems.

The ATS-M system may be overridden (in case of a shunting movement or to pass a restricting signal) by holding down the override button as the train passes over the magnet. Mechanical ATS systems such as on the U-Baner cannot be overridden except by dispatch due to the nature of the system.

ATS-M is currently being supplanted by a system known as ATS-H. ATS-H is completely digital, using beacons mounted in the center of the track similar to the HBK system, and in fact it combines the speed checking aspects of HBK with the signal checking of ATS-M. It functions in the same way as ATS-M in how it communicates with the driver. More information is in the section below.

Speed Limit Control (HBK)

Two HBK beacons (yellow plates in the center of the track) located before the ATS-M array at a signal post at the exit to a station in a village in Goyanes.

The Speed Limit Control System (Hastiketbegrensekontroll/HBK) is used to enforce maximum track speeds and speed restrictions into turnouts. It is a relatively modern system, having been created along with the A-Class signalling system in the 1990s. The HBK system supplements the ATS-M system used on classic networks by ensuring that the speed limits are not broken and that trains brake in time for switch points. The system, similarly to ATS-M or AVK, uses both trackside and onboard equipment. The trackside equipment consists of equipment boxes with microcontrollers that are connected to the signal system, and to a phone line (GSM-R since 2010 or a wired phone line before 2010) for communication from dispatch of temporary restrictions to be enforced. The microcontroller determines the signal state, and is programmed with the track speed limit, and any of the day's temporary limits. The microcontroller then transmits information to a beacon mounted in the center of the track.

A reciever on the train decodes the signal from the beacon, and sends it to the HBK computer onboard. The HBK computer compares the speed just recieved by the beacon to the onboard displayed speed. If the train is at or below the speed limit, nothing is done. If the train is within 10 km/h of the speed limit (above 60 km/h limit) or within 5 km/h (below 60 km/h limit), an overspeed alarm sounds, alerting the driver to lower the speed. If the speed of the train is above the tolerance, the emergency brakes are automatically applied and the power systems are cut.

The HBK system stores the latest recieved track speed, and keeps it in the memory for constant comparison against the speedometer until it is overriden by a new track speed picked up by the reciever from another beacon. In track areas unprotected by HBK (at the transfer point between a GJ and non-GJ line, or at the interface between the classic lines and the high-speed lines) there is a final beacon that deactivates the system by clearing out the memory bank.

The HBK system has been deployed on every single kilometer of GJ-owned classic line trackage since 1993, and has prevented countless possible speed-related accidents.

Currently, there is a program in place to convert both HBK and ATS-M into a system known as ATS-H. ATS-H would reprogram the HBK beacons and recievers to not only transmit speed control information, but to also warn about restrictive aspects, which ATS-M currently does. The system would replace the ATS-M beacons currently deployed and would save costs on broken ATS-M beaons, as the system approaches 90 years of age.

Driver Reminding Apparatus (DRA)

A DRA console in the cab of a locomotive. The DRA has been set, as the button is illuminated.

The DRA (Førermann Påminnelsemasjin/FPM) is a memory device used as an extra safety net aboard trains. Its use was mandated after the 1995 Ragnarfjord Train Crash, in which 30 people died because a driver passed a signal at danger after stopping within the safety overlap at a station platform (the signal head was not visible from the cab).

The DRA functions as a kill switch for traction on the train. It is a two-position switch, on and off. When the DRA is set, traction power is disconnected for the train. Railway regulations stipulate that the DRA must be set when shutting a train off, entering or exiting the cab, when the train has stopped for a signal at danger. The DRA may only be turned off when the train has authority to proceed (i.e. the signal clears), the driver has authority to turn on the train, or when the driver has been granted authority to pass a signal at danger by a shunting signal or by radio orders from dispatch.

Signage

Sign	Meaning
	Speed Limit; displayed in multiples of 10. In this case, 120 km/h.
	Junction Speed Limit; applies in the diverging route or track indicated.
	Advance Warning of Speed Limit; warns of a lower speed limit ahead, displayed in multiples of 10. In this case, 80 km/h.
	Advance Warning of Junction Speed Limit; warns of a lower speed limit ahead on a specified track, displayed in multiples of 10. In this case, 80 km/h.
	Advance Warning of a Temporary Emergency Speed Limit; displayed in multiples of 10. In this case, 30 km/h.
	Temporary Emergency Speed Limit; applies to all trains.
	End Temporary Emergency Speed Limit; applies to all trains.
	Raise Pantograph; The train must raise the pantograph and retract contact shoes.
	Lower Pantograph; The train must lower the pantograph and deploy contact shoes.
	Do Not Raise Pantograph; Despite the presence of overhead lines, do not raise the pantographs.
	Change In Current; The exact point where the change in current collection happens.
	Neutral Zone Advance Warning; There is a neutral zone in specified distance (meters).
	Long Neutral Zone Warning; The neutral zone ahead is of considerable length.
	Open Breakers; By this point circuit breakers must be open.
	Close Breakers; By this point circuit breakers must be closed.
	Current Indicator; Indicates the current type being used.
	End Current; The current of the specified type is ending.
	Whistle Board; The train must sound its horn or whistle when passing the sign.
	Close Air Vents; Reminder to the driver that a tunnel is approaching and they must close the air vents to avoid a pressure difference.
	Train All Stop; All trains, regardless of length or type, must stop at this sign.
	HHT Train Stop; HHT Trains must stop at the sign. The number indicates the number of trainsets that it applies to.
	Train Type Stop; Trains of the specified type(s) must stop at the sign.
	Train Car Stop; Trains of the car quantity specified must stop at the sign.
	AVK Begin; The track ahead is equipped with AVK, the system should exit standby mode.
	End AVK; The track ahead is no longer equipped with AVK, drivers are instructed to set the AVK to standby mode.
	Override ATS; The ATS transmitter is not aligned for the operating direction. Drivers have permission to override the signal.