SimSig Euston

Manual - release 1

Last modified 2011-11-15

Table of Contents

    Legal Stuff
Geographical Summary
    Electric Traction
    Camden Yard
    Routes in Euston throat
    Platform lengths
    Depot, yard, and siding capacities
    New Lines signalling
Hot keys
Fringe Working
Train Service
    Main Movements
Timetable Locations
Hints and Tips
Known problems
Other pages


SimSig Euston is based on the erstwhile Euston PSB, commissioned in the 1960s and abolished around 1999. It has been developed with the aid of detailed signalling diagrams, manuals from the prototype, and reminiscences of the staff that used to work there. I have tried to make it as accurate as practical but can't guarantee anything.

Legal Stuff

SimSig is for personal entertainment use only and must not be used for any commercial use, including the training of signallers etc. Those who are interesting in the commercial application of this software should look at

SimSig is protected by copyright. No SimSig file may be distribution by any other website, by CD ROM or other media without express written permission from SimSig Ltd. The only exception is when SimSig files are transferred between private individuals where no charge, fee or profit is levied.

This software and is offered as-is, "what-you-see-is-what-you-get". Errors, omissions, faults or other problems are not covered by any warranty of any kind. Problem reports may be emailed or posted on the forums but action may or may not be taken by the authors, a decision which is up to said authors. SimSig Ltd. accepts no responsibility for any damage that may be caused to computer systems by the software.


As ever, my thanks to Geoff and Mike for teaching me how to write simulations, to all the people who provided information, and to the beta testers.


This version was written with access to two or three versions of the official signalling plans, various other official manuals, photographs of the original signalling panel, and comments from former staff. These gave track layouts, track circuit details, available routes, and much other detail, but have various omissions. I have tried to make it as accurate as possible but no doubt there are still errors.

The simulation of Camden Yard is simplified, though the simulated areas are authentic in themselves.


The layout controlled by Euston PSB changed in several aspects over the years and I have had access to data from various dates. Rather than make one choice, the simulation can be run with three different layouts, which roughly correspond to what was found in the late 1960s, the late 1980s, and the mid-1990s.

Parcels depotPresentPresentAbsent
DC platforms8 to 109 and 109 and 10
DC type4th rail3rd rail3rd rail
Down diveunder lineEmpty CarriageDepartureDeparture
Primrose Hill layoutFullSimplifiedSimplified
NLL fringeHampstead Rd JnCamden Rd JnCamden Rd Jn
New Lines speedsStandardDifferentialDifferential

Geographical Summary

The area covered by SimSig Euston takes the West Coast Main Line from Euston to Primrose Hill tunnels, where control passes to Willesden Junction PSB. It also includes the connection from Camden Junction via Primrose Hill to the North London Line at Camden Road Junction or Hampstead Road Junction and the DC lines (sometimes called the "New Lines") towards Queen's Park. The controlled area is about a mile and a half long.

The Up direction is leftwards throughout the simulation. Up is roughly southwards from Camden Junction to Euston, and eastwards from Willesden Junction via Camden Junction to Camden Road Junction.

A quick guided tour follows. It is advisable to open SimSig Euston and follow this tour.

Starting at the left hand end, we have Euston station itself. This has either 15 or 18 main platforms; if it has only 15, then there is also the Parcels Dock. Trains can only enter the dock if given a slot.

Moving to the right, the layout divides into four separate sections. From top to bottom, these are:

Between the station and these four sets of lines lies the throat, a complex mess of pointwork. You will notice 13 blue buttons in this area, labelled A to N. These are "via" buttons - they are used to indicate which of several alternative routes are to be taken; to use them, click on the entrance signal, then the via buttons, then the exit signal. What is unusual about their use in Euston is two-fold: if a button lies on the route, it must be used, and even though there may be many potential routes between two signals, only a relatively small number of them are available. A complete list of the routes available is given later.

The shunt signals in the yard are intended for movements between platforms. Therefore there are no routes from the main lines to these signals.

Also in the throat is the train running away alarm. If a train passes signals 1 to 15, 64, or 65 at danger then all these signals will be held at danger. The alarm will flash until acknowledged (with a left click). When the offending train has been removed from the area, the alarm will flash again to indicate it needs cancelling (with a right click) before any of those signals can clear again.

At the right hand end of the backing out roads is the Down Carriage Shed. This consists of 11 roads reached via two different entrance lines. A slot is required to send a train into the shed from signal 81 on the Up Engine Line 1; if sending it into roads 1-9, you must select which of the two routes you are going to use to get it there. Furthermore, you must set the route from the last shunt signal (69 or 71) into the shed before setting the route up to that shunt signal. The slot is not required to send a train into the sheds from the various shunting necks. The latter also have opposing locking omitted, so it is possible to set up routes in both directions at the same time and let trains just shuttle back and forth.

Pulling the button labelled "Set back signals emergency replacement" (later eras only) will immediately cancel the routes on all signals for Up movements between Camden Carriage Sidings and the Down Carriage Shed, plus the exits from the latter. The button will flash red until pushed again.

After Park Street Tunnels are Camden South Junction and the Camden Carriage Sidings. This is also the area where the Up Empty Carriage Line (also known as the "Rat Hole") emerges. This line is not authorized for passenger working in normal circumstances, though passenger moves along it have been known.

Next is the Camden Junction area. Here the running lines rearrange themselves from four lines paired by direction into six lines paired by use; this is the start of the separate DC or "New" lines.

Special signalling applies on the Up Slow and Up New Lines at Camden Junction. The overlap ahead of signals 146 and 147 is not selected automatically. Instead you must select it manually. This can be done in either of two ways:

  1. When setting a route up to these signals, click on the appropriate overlap arrow after the exit signal. So to set a route from 149 to 146 with an overlap towards Primrose Hill, click on 149, 146, and then the arrow on the Primrose Hill route, in that order.
  2. The overlap can be swung by clicking the exit signal and then the overlap arrow (e.g. the above overlap can be swung towards Euston by clicking on 146 and then the arrow on the other route).
Setting a route from 146 or 147 will automatically swing the overlap if necessary.

The New Lines also had non-standard signalling during the lifetime of Euston PSB. These aspects are displayed in the simulation and explained below.

This is the end of the controlled section of SimSig Euston; the main lines then fringe with Willesden PSB and the New Lines with Wembley Suburban panel.

The other part of the simulation is the link from the North London Line to Camden Junction via Primrose Hill. This layout was drastically simplified at some point; both versions are available in appropriate eras. The link joins the NLL at Camden Road Junction; originally the fringe box was Hampstead Road Junction, but this was abolished as part of the simplification.

With the original layout, Hampstead Road Junction will ask for a slot for any train heading towards Primrose Hill. With the simplified layout no slot is required.

Finally, Camden Yard lies in the V between the main route from Euston and NLL link. It can be accessed from three places: Camden South Junction, Camden Junction, and (in some eras only) Primrose Hill. It is discussed further below.


The general speed limit over most of the line is 20mph in the station throat, 40mph on the lines south of Camden Junction, increasing to 75mph on the Slow and 80mph on the Fast lines. Most of the NLL link is 15mph. The Up Empty Carriage Line is 30mph, while the Up Engine Lines and the Down Empty Carriage Line (or Down Departure Line) are all 20mph. Access to the Down Carriage Shed is limited to 5mph, while the Up Carriage Shed and Camden Carriage Sidings are 15mph.

The New Lines vary between 30mph and 60mph. Differential speed limits are in effect in later eras: all trains that do not have either "Metro" or "Tripcock" train classes set will be limited to 25mph (passenger) or 15mph (freight).

Other speed classes may be set but will be ignored.

Electric Traction

Nearly all the layout is equipped with AC overhead; the exceptions are the New Lines and the Back Road.

The New Lines are equipped with DC electrification only. To enable DC trains to run, there is dual-electrification on the Slow Lines, a few platforms at Euston, and the NLL link. This was originally fourth-rail but was converted to third-rail at some point. For ease in writing timetables, the fourth-rail eras will accept third-rail rolling stock as well.

Camden Yard

In real life Camden Yard was controlled by its own signal box. Rather than simulate the entire yard, the three sections that control the three accesses from Euston are treated as separate ground frames.

The east end and NLL end frames are release by Euston using the buttons labelled 603 and 604 respectively. When the frame is normal and trains can be signalled past the area, the left-hand lamp will be lit. To give a release, left-click on the right-hand lamp (the green circle); this can only be done if either the line is clear for a train to depart the yard, or a train is standing at the relevant signal waiting to enter the yard. When the release is successfully given, the right-hand lamp will start to flash and the "release" light on the frame will light up. The frame operator can then reverse the "release" lever and the lamp will become steady. To return control to Euston, normalize the release lever, causing the lamp to flash once again, then right-click on the flashing lamp.

East end

The east end is the simplest of the accesses to the yard. It is used by trains arriving from the Willesden direction on the Up Fast, and for trains leaving the yard to head towards Euston.

Trains to the yard: the train stops behind signal CY45. Euston gives release 603 as described above, and the frame operator takes it. The operator then reverses the points 44 and signals the train in.

Trains leaving the yard: Euston gives release 603 as described above, and the frame operator takes it; releasing the frame allows the crossover to be reversed. Either before or after giving the release, Euston provides a slot to the frame by clicking on signals CY43 and then 116, just as if setting up a route; the route lights will light up on the panel and the slot light will come on on the frame. The frame operator can only clear signal 43 to let a train out when the slot has been granted and the points have been reversed.

NLL end

The NLL end is used by trains arriving from Camden Road Junction and for trains leaving the yard to head along the Down Slow or Down New Lines.

Trains to the yard: the train stops behind signal 131. Euston gives release 604 as described above, and the frame operator takes it; releasing the frame allows the crossover into the yard to be reversed. Euston also requests a slot to enter the yard by clicking on the "Yard" slot button next to signal 131. The operator grants the slot using lever 33, after which Euston clears 131 by setting a route from it into the yard in the normal way.

Trains leaving the yard: Euston gives release 604 as described above, and the frame operator takes it. Either before or after giving the release, Euston provides a slot to the frame by clicking on signal CY43 and then either 143 or SH7 (depending on the route the train will take) just as if setting up a route; the route lights will light up on the panel and the slot light will come on on the frame. Note that the slot can only be granted if the line is clear to the end of the relevant overlap. The frame operator can only clear signal CY43 to let a train out when the slot has been granted and the points have been reversed.

West end

The west end is the most complex access point. It is used by trains arriving from either direction on the Slow lines, and for trains leaving the yard on to the Down Slow. Unlike the other two accesses there is no release but, rather, a "transfer" area where trains pass from one control to the other.

Trains are sent into the yard proper using either of the two lines shown on the diagram, but trains from the yard will always enter on the lower one (track circuit T277).

Trains to the yard from Euston: the train stops behind signal 145. Euston requests a slot to enter the yard by clicking on the "Yard" slot button next to the signal then, when it is granted, sets the route into the yard in the normal way. On the frame this is indicated as "down slot request" and granted using lever 9. The train is then sent into the yard proper by the operator setting the points and then clearing signal CY10.

Trains to the yard from Willesden: the train stops at signal 146. Euston requests a slot to enter the yard by clicking on the "Yard" slot button next to the signal; on the frame this is indicated as "up slot request" and granted using lever 2. The frame operator must decide which of the two tracks to send the train in on and operate points 3 appropriately. The operator must also release the points from the Up NLL track into the yard using lever 1; this will cause the "points release" light on the panel to light up. Euston can then signal the train into the yard in the normal way; note that the train will get either a yellow or a subsidiary signal depending on the state of the line ahead. The train is sent into the yard proper by the operator setting the points and then clearing signal CY5 or CY8 as appropriate.

Trains leaving the yard: a train entering the simulation will wait on T277 until the operator sets points 11 and 15 correctly, after which it will move up to signal 142. Euston signals it out in the normal way.

Routes in Euston throat

The following tables list which routes are available to and from the platforms.

Departing trains

BORs 3/4BORs 1/2DFDSUSUFDiveunder
1 LL
2 and 3 JJJLL
9 and 10 BGB/HB/E/HKKM
12 CC/G
13 and 14CC
Parcels dock


To signal

Arriving trains

BORs 3/4BORs 1/2UEL1USUFUEL2UCS21222324
2 and 3 JJ/LJ/LL
13 and 14CCCNC
15 N
16-18 N
Parcels dock N


Platform lengths

The platforms at Euston have the following lengths, in metres. This is the length from buffer stop to starter signal, and does not allow for stopping space.

Platform  1400m
Platform  2340m
Platform  3370m
Platform  4320m
Platform  5270m
Platform  6270m
Platform  7310m
Platform  8260m
Platform  9200m
Platform 10200m
Platform 11260m
Platform 12300m
Platform 13310m
Platform 14335m
Platform 15460m
Platform 16365m
Platform 17275m
Platform 18165m
Siding A 56m
Siding B255m
Siding C325m
Siding D 44m

Depot, yard, and siding capacities

SimSig Euston introduces a new feature of depot capacity control. The simulation tracks the trains entering and leaving each depot, yard, or group of sidings, and will not allow a train to enter if there is not enough room or to leave if there cannot be that much rolling stock present. It also prevents over-long trains from entering or leaving.

The feature uses a simplified model based only on train lengths. The capacity of the depot is divided into "occupied", "free", and "unknown"; at the start of the simulation the entire capacity is "unknown". When a train enters, "free" space is converted to "occupied"; if there isn't enough, then "unknown" space is used to make up the shortfall. Similarly, when a train leaves, "occupied" space - or if there isn't enough, "unknown" space - is converted to "free". For example, suppose that a given depot has 500m capacity. At the start of the simulation the depot state is set to "occupied 0, free 0, unknown 500". If a train 60m long enters, this becomes "occupied 60, free 0, unknown 440". If a 100m train now departs, we know that there must have been at least 100m present, so we need to take 40m from the "unknown" space, changing it to "occupied 0, free 100, unknown 400". A 20m loco arriving alters this to "occupied 20, free 80, unknown 400". If, later on, the state is "occupied 420, free 30, unknown 50", then an attempt to bring a train more than 80m long into the depot will fail.

The depots and yards where this applies, and the available capacities, are:

Depot or yardCapacityMaximum
Parcels dock1500360
Up Carriage Shed740240
Down Carriage Shed 1-92160240
Down Carriage Shed 10-11298240
Camden Carriage Sidings2203Up end: 343
Down end: 260
Camden Yardno limitno limit
Back Road500200

Other capacities are:

Up Carriage Shed neck79m
Backing Out Roads1200m
3 and 4260m
Down Carriage Shed necks#1170m
Down Through Siding113 to 122176m
112 to 122276m
113 to 129286m

100m of each Backing Out Road is south of the mid-point signal.

New Lines signalling

The New Lines signalling is described more fully on Clive's web site, but a brief description is given here.

Stop signals have a red marker light below the main head. Repeater signals have a red marker light below and to the left of the main head. In both cases the marker light is only lit when the main signal is red. Stop signals are normally two-aspect, though signals 147 and 148 are three-aspect. Repeaters are three-aspect, though trains normally don't approach them at red. If a train is held at a red stop signal, other than 147 or 148, for about a minute, the marker light will change to yellow. This gives the train authority to proceed into the section ahead, which may be occupied. The train describer does not track trains passing signals in this way. If the train comes to a repeater signal at red, it waits a further minute and then proceeds in the same way. This means that after a failure you can end up with several trains queued buffer-to-butter at a signal.

Signal 147 has two heads; only the head applicable to the route set ahead of it will clear. Signal 148 has "direction lights". If signal 147 has cleared, signal 148 will show green in the main head and yellow in the direction light opposite to the one for the route set from 147; thus the left-hand yellow light comes on if the right-hand route is set. This gives the same visual effect as a splitting distant. The marker lights on 147 and 148 do not change to yellow.

Hot keys

The following hot keys are available:

EEuston station
MMid-way (Park Street tunnels)
CCamden Junction
WLines to Willesden
1 to 8form a sequence from Euston (1) to Willesden (8)


The New Lines can be chained on to SimSig Wembley Suburban. The signalling over this section has changed between the eras covered by the two simulations and, therefore, the chaining arrangement is a compromise (but each simulation should appear sensible). At Camden Road Junction facilities have been included to chain to future releases of SimSig NLL.


The scenarios are self-evident.

The train describer on the real Euston panel did not cover shunting moves and tracks such as the Backing Out Roads. When starting a simulation you have the option of realism or to have additional train describer berths for these lines.

Fringe working

At any of the places where a train can enter (Parcels Dock, Up and Down Carriage Sheds, Camden Carriage Sidings, Camden Yard, Camden Road Junction, and from the Willesden Junction area) the fringe box can be told that the line is blocked by putting a special code into the relevant train describer berth:

Note that for the lines from Willesden, the relevant berths are:

Train Service

The supplied timetable is based on the workings of Summer 2003. Despite this, it should work in all eras, though this means some trains have been replatformed and some other minor changes have been applied. It runs from 03:00 to 04:00 the following day (shown as 28:00), though the last timetabled move ends at 27:07.

There are a total of 724 schedules in the timetable involving 421 trains entering the simulation. There are a number of divides and joins.

Train 0S26-1 uses the Up Carriage Siding neck. This is not available in the 1990s era and the train will need to be retimetabled by hand.


Standard railway descriptions (headcodes) are used. The first digit is the class of train. The second character is a letter, which usually denotes the route taken by the train. The remaining two digits simply give each train its own identity.

The train classes are:

1Express passenger train
2Local passenger train
3[not used] Parcels train or priority empty coaching stock
4Fast (75mph) goods train
5Empty coaching stock
6Medium (60mph) goods train
7Slow (45mph) goods train
8Very slow goods train
9[not used] International or priority passenger train
0Light engine

The route letters found in the timetable are as follows.

Services within the former Midland Region

Long-distanceMedium-distanceNew Lines
ATo LondonMilton Keynes area
BNorthampton, Rugby, and Birmingham
CTo Lancaster and CarlisleFrom Watford Junction
DTo HolyheadTo Watford Junction
FTo Liverpool
GTo Birmingham and Wolverhampton
HTo Manchester
PTo Crewe and Preston
WPeak services

The letters I, J, K, N, Q, R, T, U, and Y are also reserved for services within this region, but are not used in the timetable.

Other services

ETo former Eastern Region
LTo former Anglia Region
MFrom other regions
OTo former Southern Region
STo former Scottish Region
VTo former Western Region
X[not used] Out of gauge workings
ZSpecial workings

Main Movements

Virgin Trains

Virgin Trains run services in and out of Euston. These are mostly Pendolinos that do not fit in all the platforms.


Silverlink (now London Midland and London Overground) run services in and out of Euston using both AC and dual-voltage EMUs (for the Watford Junction service that uses the New Lines). There is some joining and splitting at Euston, and some ECS workings to the various sidings and sheds.


Scotrail run the sleeper services that arrive in the morning rush-hour and depart late evening. These are very long (16 coaches plus loco) and only fit in a few platforms.

Freight Services

There are some freight services, mostly running to and from the North London Line.

Timetable Locations

This section lists the internal codes (which in many cases are TIPLOC codes) for the timetable locations in the simulation, and also provides a brief description of the less-obvious locations. These codes are used when using the timetable converter.

When a train enters the simulation a different code - an entry point code - is used. These codes are shown in italics following a » symbol. In general, the entry location should not be the first location in the train's timetable as well.

EUSTONEuston: all platforms.
EN16Parcels Dock: (some eras only) » EPCLD.
EN27Euston S27.
EN2126Euston S21-26 (rev.).
EN2847Euston S28-47 (rev.).
EN4951Euston throat: signals 45, 49, 51, 52, and the limits of shunt on the Up Fast and Up Slow.
EUSTNHSUp Carriage Shed neck.
EUSTUCSUp Carriage Shed: » EUCS.
EUSTBORBacking Out Roads.
EUSTRESDown Carriage Shed: » EDCS1 (1-9) and EDCS2 (10-11).
EUSTDCNDown Carriage Shed shunt neck.
EN89Signal 89 (reverse).
EN9192Park Street Tunnels: signals 91, 92, 94, and 105.
CMDNSTHCamden South Junction: all lines including the "Rat Hole".
CMDNCSDCamden Carriage Sidings: both ends. » ECCSU (Up end) and ECCSD (Down end).
CMDN113Camden Down Through Siding: signals 113 and 122.
CMDN134Camden north end: Down Fast behind signal 134.
CMDNYECamden Yard entrance: CY5/8/10; only needed if timetabling these locations separately from actually going into the yard.
EN142Camden Yard: trains actually going into the yard. » ECYU (Up Fast), ECYD (Camden Junction), and ECYN (Primrose Hill).
CMDNRDJCamden Road Junction: » ENLL.
HRJHampstead Road Junction: » ENLL.
PRIMRSHPrimrose Hill.
EN128Back Road: » EBACK
CBACKBack Road neck.
EN131Down NLL (signal 131).
CMDNJNCamden Junction: all lines.
CMDN146Camden Junction (rev.): Down Slow behind signal 145, for reversing moves into Camden Yard.
SHMPSTDSouth Hampstead: New Lines.
KLBRNHRKilburn High Road: New Lines » ENL.
WLSDWLJWillesden WLL Junction: Fast and Slow Lines » EFAST (Up Fast) and ESLOW (Up Slow).

The timetable locations "Camden Road Junction" and "Hampstead Road Junction" are equivalent; both are provided to allow timetables to appear more realistic.

Hints and Tips

Don't forget the via buttons in the throat and the overlap buttons at Camden Junction.

Known problems

None at present.

Other pages

Route tables for signallers
The original instructions for Euston PSB