Talk:Token (railway signalling)

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[edit] Token or Staff?

An anonymous editor has just changed quite a few uses of the word "staff" to "token", it being the generic term.

In one sense, it is reasonable to do this, and the article did contain a mixture. But it grates with me, as I have never heard the work "token" used in real life. That is, all the "token" systems I have known here in Oz are referred to as staff systems of one sort or another. What I am wondering is, just how widespread is use of the word "token"? And more to the point, are some of the compound terms, such as "temporary staff station" ever used in connection with systems where the term "token" is used? I suggest that using the term "temporary token station" is incorrect if that term is never used in real life. The article now says that "The stations at each end of a Token section are known as Token Stations." But are they ever actually known as that? (Actually, I did find one or two in Google, see below.)

Using Google, I came up with the following:

  • "temporary token station" — no hits
  • "temporary tablet station" — no hits
  • "temporary staff station" — 4 hits (hmmm, that's not many either, is it?), all from Victoria


  • "electric token" — 185 hits
  • "electric tablet" — 127 hits
  • "electric staff" — 12,500 hits


  • "token station" — 181 hits (most were to do with token ring networks. Only two out of the first 30 hits were clearly to do with safeworking, and one of them was from another article on Wikipedia.)
  • "tablet station" — 76 hits (a high proportion safeworking-related, it appears)
  • "staff station" — 24,400 hits (most were not to do with safeworking. Again, two in the first 30 were, but neither were on Wikipedia.)

Can anyone else fill us in on actual usage of the different terms?

Philip J. Rayment 14:24, 23 September 2006 (UTC)

As I understand it, electric staff instruments were widely used in Oz. In the UK, their use was far less common than the tablet or key-token instruments. The generic term "Token" was and is widely used here. For example, the method of working is officially called "Electric Token Block", and Weekly Operating Notices would contain statements like "[Name] signal box will be closed as a token station".

I am puzzled by your use of the term "Temporary Staff Station". Do you mean this to refer to a Staff/Token station with the facility to be switched out when not required? In the UK, we would never refer to such an installation as "temporary". 84.65.176.129 20:29, 23 September 2006 (UTC)

Thanks for that information. It seems that, on the whole, using token over staff is probably appropriate. You are correct about the 'Temporary Staff Station'. I don't know the origin of the terminology, but we did have quite a few places that were only opened as Staff Stations seasonally. Philip J. Rayment 11:45, 24 September 2006 (UTC)

Here in the UK the term token was frequently used. So much so the GWR applied ETT (Electric Train Token) regulations.--7severn7 08:43, 17 October 2006 (UTC)

UK usage was that originally everything was a Train Staff, and later a Train Staff and Ticket system. When electric interlocking of instruments became practical, some manufacturers continued with staffs, and the system was called Electric Train Staff. The train staff was easy to hand to a driver, but a collection of train staffs retained in the instrument in the signalbox was very bulky. The instruments had a slot and the staffs rpotruded, but could not be irregularly removed.

A development therefore was to use a smaller thing to hand over ot the driver; what should it be called? Well, it was a token of the safety of entering the single line, and it was called a token. Its usual form was a round disc like an oversized ice hockey puck, and these were often called "tablets". The instruments accepted the tablets in the way that a cd is placed on a tray in the cd player. Many railwaymen called the system "the tablet system".

However the GWR and BR(W) especially favoured a system where the token was like a very large key, that could be turned in the instrument to operate it, and these didnb't look anything like a "tablet" so the term "token" was used. The system was "the electric train token" system.

But I have never heard the word "token" used except in the context of an elctric token system, and I worry that the title of this article is off-putting

But all these terms are interchangeable and subject to local usage and misusage. Afterbrunel 21:16, 30 July 2007 (UTC)

There were largely two variations in useage, 'staff' and 'token'. Which term was used depended on the actual configuration. The 'wooden staff' system used a wooden pole which could be confused with a two foot section of broom handle. It had brass plate screwed to it which gave the two signalboxes between which it was valid. The 'staff and ticket' system used a similar staff, but with a key for the ticket boxes permanently attached.
With the advent of electric token systems, two distinct departures occured. William Tyer got in first and developed his electric tablet machine. The tablet looked nothing like a staff and so was refered to as a 'tablet' (though some companies called it a 'token') and the whole system refered to generically as 'electric token'. However Webb and Thomson then produced an instrument that used wooden staffs with brass rings along their length (to make them unique to each pair of instruments - an interesting description for a large cast iron machine that stood about one and half metres high). This system was refered to as the 'electric staff' system (but was operationally more or less identical to the Tyer's system - so much so that Tyer sued succesfully). This was favoured by some rail companies over the Tyer's systems (notably the Southern Railway).
Staff systems (of any type) had operational problems in that the staff often rolled off the locomotive foot plate, closing the token section until it was found. Tyer's tokens were usually placed in a pouch with a hoop (to aid collection and surrender by the fireman). The hoop could then be conveniently hooked over a convenient valve on the locomotive footplate. Tyer's later machines used a key shaped token rather than a tablet. With the passing of steam, the token is rarely placed in a pouch these days as the driver is required to stop to collect and surrender it.
Thus the term 'staff' is used for 'broom handle' shaped tokens and 'token' is used for just about anything else. Generically though either system is known as the 'electric token' system in virtually every reference work. Most electric token systems in use on British Network Rail operated lines today are of the key type electric token (the Tyer's No. 9 system being the most prevalent). Of course, other countries terminology can vary.20.133.0.14 14:15, 28 August 2007 (UTC)

[edit] Intermediate Block Posts

I think the recently-added section headed Intermediate Block Posts is superfluous. The subject is already covered under Intermediate Token Stations. Note the wording "The facility may be provided that will allow the Token Station at B to be 'switched out' when not required,...". In the event that this facility is not provided, then what you have is the same as what's being described as an 'Intermediate Block Post'. Also, the wording of the new section suggests that it is only applicable to train staff & ticket, whereas the same principle is used with the electric token system. 81.79.143.39 10:54, 25 September 2006 (UTC)

(As the author of that section...) I don't agree that it is the same thing, and therefore that it is superfluous. I don't follow your comment that "In the event that [an Intermediate Token Station] is not provided, then what you have is the same as what's being described as an 'Intermediate Block Post'". If you don't have an Intermediate Token Station, a following train cannot depart A until the preceding train arrives at C. With an Intermediate Block Post, although the token section is still A to C, a following train can depart A when the preceding train has arrived at B. That's clearly not the same thing.
An intermediate block post is only possible when trains follow one another on a ticket (including the last one carrying the token). It is therefore not applicable to Electric Staff, except for the rare(?) occasions that the electric staff is a divisible one with ticket portions. However, apart from a reference to the ticket (and no mention of a ticket portion), there is nothing in the section to limit it to Staff and Ticket working; it could equally be read as applying to Electric Token working.
Philip J. Rayment 12:39, 25 September 2006 (UTC)
Rereading the section, perhaps I did not explain it clearly enough. I have now added a couple of words to (hopefully) make it clearer. I'm open to suggestions on making it clearer still. Philip J. Rayment 12:45, 25 September 2006 (UTC)
Consider a token section from A to C. Both A and C are token stations with passing loops. Due to the long distance between A and C we decide to split the section in two, by setting up an intermediate token station at B, where there is no passing loop. We now have sections A to B and B to C, and both sections can be occupied simultaneously provided that both trains are travelling in the same direction. This scenario (let's call it [1] for the purposes of this discussion), is described at the beginning of the section headed "Intermediate Token Stations".
If I only need this facility during certain busy periods, I can add further apparatus to allow the intermediate token station at B to be 'switched out' and unstaffed, and the section worked as A to C ('B' is now what you earlier called a 'temporary staff station'). This is described later on in the section "Intermediate Token Stations". Let's call this scenario [2].
My gripe is that the new section headed "Intermediate Block Posts" seems to go back to describe scenario [1] over again - an intermediate token station that cannot be switched out.
You have mis-read what I wrote above. I didn't write "In the event that [an Intermediate Token Station] is not provided, then what you have is the same as what's being described as an 'Intermediate Block Post'". I was actually saying: "In the event that an Intermediate Token Station does not have the facility to be switched out, then what you have is the same as what's being described as an 'Intermediate Block Post'".
I propose that the "Intermediate Block Posts" section be deleted and, if necessary, further amplification be added under "Intermediate Token Stations". 84.71.88.149 13:33, 25 September 2006 (UTC)
There are two problems.
  1. Switching in B as a Token Station without a crossing loop may result in two trains departing both A and C for B at the same time, which will cause something of a difficulty for the signalman at B to sort out. So whilst it may not be actually unsafe, it is a rather risky thing to do. An Intermediate Block Post avoids this problem.
    An Intermediate Block Post is not the same as an Intermediate Token Station that cannot be switched out (and by the way, if it couldn't be switched out, it wouldn't be called an Intermediate Token Station), because the latter requires separate Staffs (and tickets and ticket boxes) for each of the two sections, instead of the one section.
    By the way, implicitly as written, and often in reality, the Intermediate Block Posts are not permanent, but temporary (switchable). So if it was the same as an Intermediate Token Station, it would be the same as one that does switch out.
  2. More importantly, we are not discussing possible ways of solving a particular problem, but actual ways. Even though it may be possible to solve the problem with an Intermediate Token Station, in practice, it is often done with an Intermediate Block Post.
Philip J. Rayment 16:43, 25 September 2006 (UTC)
May I suggest that the two sections under discussion are transposed? Train staff & ticket should be dealt with before electric token, the former being an older system. Also, this would leave any mention of switching out (temporary) token stations till last.
(Electric) token stations did exist at places with no crossing loop. There are means of preventing two trains being simultaneously admitted towards such a token station, albeit this was not always implemented. This issue is relevant regardless of whether the token station is able to switch out. 84.66.183.102 17:34, 25 September 2006 (UTC)
I did wonder about transposing Intermediate Token Stations (ITS) and Intermediate Block Posts (IBP). I don't know which came first historically, but either one could be described as a variation of the other. I might make that change tonight.
But what do you mean by "Train staff & ticket should be dealt with before electric token, the former being an older system."? S&T is dealt with before ET. Or are you equating an IBP with S&T and ITS with ET? I indicated above that IBPs would normally only be used with S&T, but ITSs are used with both.
I accept that Token Stations could be provided at places without crossing loops, even though it would not be the best way of breaking such a section. However, you mention ET Stations in this context. With ET, unless you are using a divisible Staff, an ITS is the only way to do it, and could probably be managed (i.e. preventing two trains going towards each other) somehow with the electrical connections/logic. Neither point (the necessity and the electrical connections) apply in the case of S&T.
Philip J. Rayment 03:18, 26 September 2006 (UTC)
I have transposed Intermediate Token Stations and Intermediate Block Posts as discussed above. Philip J. Rayment 10:08, 26 September 2006 (UTC)
The question that I think needs covering is the issue of what I will call 'double tokenning' that is Train 1 leaves A with token alpha it then arrives at block post B and send its Train Arrival Message (TAM), Train 2 can now leave A (presumably with token beta?) and therein lies the problem how did the system cope with two active tokens? Wilmot1 13:20, 24 May 2007 (UTC)
Isn't this addressed by the Electric Token system, where there are many tokens for the section available at both ends of it, but only one can be extracted? 20.133.0.14 09:34, 29 August 2007 (UTC)

This section may be accurate but I am not sure it will help the novice reader. Anyway isn't the term "long section working"? Afterbrunel 21:16, 30 July 2007 (UTC)

[edit] Suggested Merge

I suggest that Automatic Token Exchange be merged into this article. There doesn't appear to be enough that can be said about Automatic Token Exchange to justify an article of its own. Of the three paragraphs that currently make up that article, the last is just a short description of the electric token system and nothing specific to the title subject. Most of the information given there already exists in the "Token" article. Signalhead 19:50, 15 February 2007 (UTC)

Done. Signalhead 18:16, 14 March 2007 (UTC)

[edit] Confusing?

I notice that the IP poster who gave this article the {confusing} tag originally applied it to the "Intermediate token stations" section only. The whole article doesn't deserve the tag; I propose to put it back to its original position, subject to other editors' views. If I had the knowledge, I'd try to clarify the paragraph myself. --Old Moonraker 12:55, 6 April 2007 (UTC)

Moved back to original position. --Old Moonraker 12:56, 11 April 2007 (UTC)

[edit] Supposed use of the 'Token only' system on 'long through lines'.

This text was recently added below the heading Token only:

However the system was used on long through lines as well; R H Dutton, Chairman of the London and South Western Railway explained in 1876 the slow journey time between Exeter and Plymouth by saying, "the cause of the delay is the stopping at every station on the staff system. That really does cause a great delay because if the staff is not there, the train must stop while a man is sent on a horse to get it [from the other end of the section]"; quoted in Williams.

I'm not convinced that the quoted text proves the use of the Token only system on a 'long through line'. It could have been a reference to the Staff and Ticket system, in which it's equally possible for the staff to be at the wrong end of the section if things don't run according to plan. Signalhead 21:51, 16 September 2007 (UTC)