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Switching Box in/out ?

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Switching Box in/out ?

Unread postby Paul_G » Thu Dec 15, 2016 3:07 pm

Hi folks

Forgive me for picking your brains once again.

In the signalling module of "The Railway" simulator I have placed a box in/out switch. and am progressing quite well with enabling the box to be either........

"Auto" ( fully automatic recieving and sending bell codes and operating the main signal)

"Manual" ( you will recieve bellcodes from "Auto" boxes either side but tap in your own bellcodes and pull your own signals )

For programming reasons it would be better for the box to be Auto by default and then once switched in becomes manual.

So my question(s) are

Switching boxes in /out in a rural location quite normal practice ?

When switching a box out would it be normal to put all the main signals to "OFF" then switch out ?

I presume when switched out the Block instruments would be bypassed so as to be "Blocked" ?

If my thinking is correct in the game ATM you would enter a box that is fully auto and the box switch is set to OUT.
(this wouldn't strictly be correct as all the signals and codes would be working by auto)
But it does enable "spectator" mode to watch/ learn the box operation.
The player could then switch the box IN and it becomes manual.. and he operates the box himself
Switching the box OUT would revert it to "Auto"
This would be a two mode system. Auto, Manual

Is this too much of a stretch ?

If I go for a three mode System....
Auto
Switched IN... Manual
Switched OUT.... everything Bypasses the box

In the switched out state, I am presuming this is when all signals would be off as mentioned above ?
The problem would be getting from Auto state to OUT then IN

I think I have answered my own question about 2/3 mode but what do you guys think ?

Cheers

Paul G

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Re: Switching Box in/out ?

Unread postby StevieG » Fri Dec 16, 2016 2:46 am

Paul_G wrote: " Hi folks

Forgive me for picking your brains once again.

In the signalling module of "The Railway" simulator I have placed a box in/out switch. and am progressing quite well with enabling the box to be either........

"Auto" ( fully automatic recieving and sending bell codes and operating the main signal)

"Manual" ( you will recieve bellcodes from "Auto" boxes either side but tap in your own bellcodes and pull your own signals )

For programming reasons it would be better for the box to be Auto by default and then once switched in becomes manual. .... "
Paul,
Most of what I write below is based on the assumption that you are talking about a box switching out which operates the 'traditional' Absolute Block Regulations system, on a double-track route.
If I am wrong on the Absolute Block assumption, please refer to my last main paragraph.
- [ Signal boxes controlling single line routes are affected by some rather different factors and have different equipments, and for those which can switch-out, the switching out procedure involves very different switch-out facilities : I'm sorry that I am not well acquainted with such installations.]


I effectively know nothing of railway simulations so I am not necessarily clear on specific detailed meaning of some of your phrasing (such as a Box in OUT status, receiving and sending bell codes), but will try to answer at least some of the points of your query
Paul G wrote: " .... So my question(s) are

Switching boxes in /out in a rural location quite normal practice ?
At many, but not all, 'Yes', provided that such boxes do have a 'Block Switch'.
Paul G wrote: " .... When switching a box out would it be normal to put all the main signals to "OFF" then switch out ? .... "
Whilst historically this would have been physically possible where the box's last stop signal on each line could be pulled to 'Off' at any time - Only the Rules & Regulations stated when this should or should not be done (no electric locking of the signal, released by the advance (=ahead) section Block Instrument being at 'Line Clear') : Any remaining such no lock/always free situations on Absolute Block passenger lines, if any, would now be quite rare - Might also still be a few on the now rare running lines worked by Permissive Block Regs.), the Block Regulations required the switching out bell-code and switch operation to be complete before pulling the running signals to 'Off' (= 'Clear) : Where a box's last stop signal(s) are 'released by the Block' the clearing of the signals to 'Off' has to typically be done during the switch-out bell procedure, with 'turning' the Switch to 'Out' being the last action of all.
Paul G wrote: " .... I presume when switched out the Block instruments would be bypassed so as to be "Blocked" ? .... "
... if you mean as in the 'Blocks' would be left showing (depending on age/type/installing organisation's stipulation) "Normal" or "Line Blocked" all the time, then Yes.
And the signals cease to have any role in protecting a Block Section or keeping trains apart.
Paul G wrote: " .... If my thinking is correct in the game ATM you would enter a box that is fully auto and the box switch is set to OUT.
(this wouldn't strictly be correct as all the signals and codes would be working by auto)
But it does enable "spectator" mode to watch/ learn the box operation.
The player could then switch the box IN and it becomes manual.. and he operates the box himself
Switching the box OUT would revert it to "Auto"
This would be a two mode system. Auto, Manual.... "
I don't understand "ATM", but I think the answer is Yes :
Except possibly; how would anyone 'learn the operation of a box' when, if prototypical for a box that is currently switched-out, no signal controls, bells or block instruments operate/are operated?
Paul G wrote:" .... If I go for a three mode System....
Auto
Switched IN... Manual
Switched OUT.... everything Bypasses the box

In the switched out state, I am presuming this is when all signals would be off as mentioned above ?
The problem would be getting from Auto state to OUT then IN

I think I have answered my own question about 2/3 mode but what do you guys think ?

Cheers

Paul G "
From what I have quoted from you below my previous comment, I am a bit unsure about what you're describing; e.g. what the difference is between your "Auto" and "Switched OUT - everything bypasses the box".

My comments above assume the possible states of a real box, which can be either in-switch (or 'is switched in') or out-of-switch ('switched out') : 'In' seems obviously to accord with your 'Manual'; When switched out, all signal controls for through running are set to have the signals 'Off' and the bell and Block circuits to the box on each side are connected together and the bells and 'Blocks' in the switched out box are inactive : So that in the typical principles training example of boxes designated A, B, and C, it is then as if Box B does not exist (is completely bypassed) until switched back in again, and the Block Section (to which the standard principle 'only one train, in one section, at any one time' applies) is then A to C.
Incidentally as to the indications displayed by the signals themselves while the box is 'out', mechanically-worked signals will just remain showing 'Clear' at all times : Electrically-worked signals (motor-worked semaphores, or colour-light signals), depending on considerations which might vary according to regional/area practice, may do the same; or, if normally, when the box is 'In', are also governed by any track circuit(s) beyond them, when the box is 'Out', they may still change to their most restrictive indication when a train occupies that track circuit(s), but then resume being 'Clear' when said track circuit(s) are again clear.

One additional possibility regarding the actual Block Switch; depending on pre-BR company / BR Region/area practices / preferences, or local circumstances; some boxes, rather than their Block Switch having just IN / OUT positions, had (/may still have) 3-position switches.
A 3-position Switch's IN and OUT positions have exactly the same effect as 2-position Switches, but the third position (I believe, usually termed 'Intermediate' or similar) eases the switching-in process. :-
- An Absolute box is normally only allowed to switch out when all sections to the boxes on either side have neither a train signalled (Block Indicator showing 'Line Clear') nor in-section (Block Indicator showing 'Train On Line' or equivalent), so the 'Blocks' should be at 'Normal' or 'Line Blocked'.

Referring back to the boxes A - B - C example, with Box B switched out, B is not normally permitted to switch in while any Box A - Box C 'Block' is at 'Line Clear', but can do when the A - C sections are either at 'Normal'/'Line Blocked', or have a train in section, so the relevant Block indicator(s) would be at 'Train On Line' or equivalent (in which case when switching in, the signals for the occupied section(s) must be left 'Off' until either the train passes or 'Train Out Of Section bell-code is received from the box in advance.)[/i].
So, for a signalman at B to switch-in, and remembering that initially all the Block indicators in the switched-out box (B) will at this stage be inactive, the signalman needs to find out if/when he/she can switch-in by finding out the state of the Block sections.
With a 2-position Block Switch this can realistically only be ascertained by telephoning Box A or C : But a 3-position Switch's 'Intermediate' position, while not allowing the signalman wanting to switch in at B to influence/alter the state of the A-C Section's instrumentation, it does allow him/her to see the A-C Section's indications repeated on his own Block Instruments' advance sections' indicators, and so can straight away see for him/herself when the status of the A-C Sections permits the box to be switched in.

If you are interested in the 'switching out' of a Box not involving Absolute (or Permissive) Block; the likely other example situation would be boxes on fully track-circuited lines typically operating running signals which are only of colour-light type, and operating to the Track Circuit Block Regulations.
This sort of arrangement has also existed, but with increasing numbers of instances of concentrated centralisation of signalling control/supervision on large control centres over the last 50 years, I think it doubtful that any such installations still exist.
When unmanned(/'switched out'), these boxes' signals would be left set to continue to function automatically with the passage of each train, protecting the section ahead and thus keeping trains apart [is this what you mean by your 'AUTO'?] : For purposes of applying certain parts of the TCB Regulations and rules in particular problem situations, the signals controlled by the box when it was manned(/'switched in') were, officially, differently identified as Semi-Automatic (and their I.D. plates additionally bore the word "SEMI").

I hope at least some of this epistle is of help/interest, Paul_G : And I stand ready for others to expand, correct, or clarify what I have written.
Last edited by StevieG on Sat Dec 17, 2016 3:03 am, edited 8 times in total.
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Re: Switching Box in/out ?

Unread postby Mike Hodgson » Fri Dec 16, 2016 8:00 pm

Just to expand slightly on Stevie's comments, switching in/out isn't just a matter of flicking a switch at the appropriate time. The most common arrangements are explained in Regulation 24 of the 1960 Regulations for Train Signalling, and there were numerous detail revisions to that particular rule over the years, and quite a few differences between older regulations of various pre-nationalisation and pre-grouping companies. However it was not all that unusual for a box have different technical arrangements requiring local instructions.

Both opening and closing procedure include an exchange of bell codes, as listed below. Switching out generally bypasses the bells as well as the blocks, so you need the switch at the IN position to do this.
5-5-5 when opening the box
7-5-5 when closing, provided the starters are not locked by the block (nowadays most unusual)
5-5-7 when closing if they are.

The reason for the 5-5-7 code is that basically it means "set your block to Line Clear so that I can pull my starting signal".
Both types of closing could even be encountered at the same box where the block controls the the starter in one direction but not in another. If the signalman sent these codes on both instruments at once, the resulting acknowledgment was quite a cacophony.

If the box has Welwyn Controls and a release is required purely to free the starter (ie although there is no train) then it is also necessary to wind out the Welwyn delay.

When the box has been switched out, the signalboxes on either side should exchange the Testing signal (16 bells), to confirm that they can indeed work normally without the intermediate box in circuit, and the signalman going off duty should not leave until they have established this.

As to whether the ability to switch was common, it often wasn't provided on single lines (special instruments had to be supplied for long section working) so many branch lines just closed after the last train of the evening. On double track through routes traffic was often much less frequent at night so selected boxes were given switches. However it wasn't usually possible to switch out where there was a level crossing which had to be manned, although some such boxes especially on the Eastern Region could switch out as a block post, still reducing line capacity to only one train between A and C, but the signals were left at Danger to be worked by a crossing keeper at B (on a lower rate of pay, much shorter training period required). So yes, it was quite common on through routes for boxes to switch out during quiet periods (overnight, Sundays, or if there was a problem of staff shortages). Even some major boxes had switches, but only closed for a few hours on a Sunday when staff changed from day to night shifts etc. And there were also boxes at quiet wayside stations which were switched out most of the day, only opening for an hour or two to enable a daily goods train to be shunted). There was a grade of Porter/Signalman where the man would spend most of his shift on other duties but was qualified to work the box for the short period it was needed. Even some important boxes have a closing switch, although in practice it may be used only for the Xmas shutdown.

With certain layouts it was necessary to have different interlocking when the box is closed, notably on single lines where locking generally prevents you clearing signals for opposite directions at the same time; this would require the provision of a "King" lever whose function was to re-arrange the interlocking as required.
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Re: Switching Box in/out ?

Unread postby Paul_G » Mon Dec 19, 2016 12:11 pm

Thanks Guys,

As I suspected there is quite a lot involved switching a box out.

For now I think I will not be simulating switching in / out but I will be using the Block switch to move from Auto (spectator mode) to manual (player) operation.

I could re-visit this in the future

Thanks again

Paul G
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