Using signal levers to power multiple DC block sections

[Lacathedrale]

Hi all,

 

I am working on a steam-era terminus layout. I want to control the signals and points with a Scale4Society lever frame. The lever frame includes the provision of a single micro switch per lever. I'm thinking of using MTB MP-1 point motors, which route power from the relevant turnout stock rails to the frog (rather than from their own power source). This should be fairly straight forward to implement (before I get into interlocking )

 

Over time I would like use signal levers to a) energise sections and b) have them controlled by the relevant controller (either layout or fiddle-yard). The ability to do this has a bearing on whether I go with DC (as my preference) or have to switch to DCC.

 

In the real layout there are 18 levers and 16 power sections and I have already mapped out which track sections each signal lever will need to energise, and which controller that will need to go to - but I was hoping that someone with a bit more knowledge of electronics might be able to sanity check on how an example might look physically if that's OK?

 

Here's an example diagram:

 

There are only four signals (red numbers) and five sections (letters) in this one, so if I pull off:

 

•  1, I want to route A, X and C to the FY controller
•  2, I want to route B, X, C to the FY controller
•  3, I want to D, X, A to the layout controller
•  4, I want to route D, X, B to the layout controller

 

Electronically, how would this look? I'm sure it's quite simple but I just don't have the knowledge!

 

Thank you so much!

 

 

Edited December 16, 2021 by Lacathedrale

[LNER4479]

Hi,

 

Whilst not answering your question precisely, I pretty much do this on my Grantham layout (LNER 1930s; DC). One thing I learnt quite quickly was that I needed to use relays as you actually want multiple functionality from one throw of a lever. Not a scary as it first sounds - you just work your way systematically through each circuit one at a time. Pulling a lever on the layout might variously:

• Connect power to the track
• Set up a circuit for a subsequent lever pull
• Raise a signal arm
• Interlock associated points and signals

I think my current 'record' is one lever actually doing 10 things electrically, via the associated relay contacts. My trackplan is somewhat more complex than yours, I hasten to add!

 

I've used Heathcote Electronics relay boards - no soldering required (all done for you). Usual disclaimer, other than to say we've been to more than a dozen exhibitions with the layout since 2015 and it's all held up remarkably well.

 

There will of course be equally as many alternative approaches out there ... including the DCC guys no doubt holding the head in their hands.

[Lacathedrale]

Hi there!

 

So the lever frame microswitches are instead switching relays to set multiple feeds - rather than literally making and breaking those feeds themselves? I can understand that from a neatness perspective, but I'm still not much wiser on how it might look in practise - thank you either way,

 

William

 

[t-b-g]

This was a wiring diagram I did for Platform 2 at Buckingham, which shows how the starter signal transfers power to Grandborough Junction (in your case the fiddle yard controller) and how all the arrival, shunt ahead and calling on signals connect the Buckingham controllers to either the whole platform or just half of it. There is a manual plunger over-ride for any moves not covered by the signals, for example if a loco trapped at the buffers wants to go to the far end of the platform but you don't want to pull the signal for it to go further.

 

On Buckingham, the rest of the departure line beyond signal 2 is connected to Grandborough by the advanced starter signal.

 

As drawn, Pl 2 is on the Grandborough controller but when 2 is back in the frame, any of the other signals will connect the Buckingham controller to one part (all the shunt signals) or both parts (No 19) of the track.

 

Signal 40 is not really very prototypical but could be replaced by a push button or toggle switch rather than a lever.

 

 

  I hope that helps.

[Lacathedrale]

Hi Tony,

 

I'm going to have a cup of tea and scrutinise that wiring diagram, thank you!

 

My first question upon looking is 2 - does that imply the platform is always live for Grandborough? Is that just a factor of it being single pole, two throw switches in the lever frame? Or does the Grandborough controller have some other switching involved? (I would have thought this would be repeated on all platforms, and having all of them live to GJ simultaneously sounds like a recipe for disaster).

 

My second question is, is the plunger shown between 43 and 44 used to give power to the A section to allow a loco to move from the middle to the end of the platform, and 40 is used to get it from the buffer stops to the middle of the platform?

 

My third question is, are you using common return wiring, or switching both rails? I can only really seem to find discussions of angry american basement-empire builders talking about it...

 

William

 

Edited December 16, 2021 by Lacathedrale

[t-b-g]

3 minutes ago, Lacathedrale said:

Hi Tony,

 

I'm going to have a cup of tea and scrutinise that wiring diagram, thank you! My first question upon looking is 2 - does that imply the platform is always live for Grandborough? Is that just a factor of it being single pole, two throw switches in the lever frame?

 

William

 

 

Hello William.

 

Signal 2 is a simple single pole changeover switch with no "off" position. When 2 is pulled (as drawn), the track section B is attached to the Grandborough Controller. Section A remains isolated.

 

When 2 is back in the frame, the track is attached to the upper contact, which then goes to a series of on/off switches to the Buckingham controller.

 

When lever 2 is back in the frame, the whole platform is isolated.

 

To arrive, 19 has a double pole switch, which puts both A and B onto the Buckingham controller. That is the only one which energises both sections of the platform road. Only 19 and 40 energise section A. All the other shunt/calling on signals energise section B, so you can shunt in and out with a loco isolated at the buffers.

 

When a train departs, as soon as the loco has passed signal 2, you can put that back, then use 40 plus the manual plunger to follow the departing train up the platform. The train being on the GJ controller with the departure line switched by advanced starter signal number 7 (not shown on the diagram but illustrated in the video) and the trapped loco goes down the platform on the Buckingham one.

 

The diagram was drawn at the request of somebody who watched the video about the control systems but couldn't quite grasp it without a diagram, so if you have a look at the video in conjunction with the diagram, I think that may clarify things.

 

As this is a new thread, I will add a link to the video for anybody who hasn't seen it and might want to:

 

 

Cheers

 

Tony  

[Lacathedrale]

Thanks Tony, I've watched the video a few times, but with the diagram to hand too I think it would be worth another visit.

 

Confirming that 2 was drawn as pulled, and the confirmation of the use of 40 and the plunger is super. I think it's coming together in my mind - conceptually it seems to be linking each platform road to a subsidiary wiring bus that is then toggled for the arrival or various shunt operations to a local controller, or departure to the next controller seems sane.

 

I'm happy I don't have to do this work (apart from isolating sections) up front though, gosh - feels like there's a a few head scratching weeks of designing circuit diagrams...

 

ps. I got the inspiration for signal-controlled DC blocks from another layout. Oh it was ... Great Western? You wouldn't know it, it's on another forum sorry..

 

Edited December 16, 2021 by Lacathedrale

[DCB]

It sounds both over complicated and lacking in flexibility.

If you are operating pre BR Blue era the engine which brings in the stock needs to be removed,

The section from buffer stops to platform starter  needs to change from one controller to another as soon as the train engine is clear of the signal so the incoming engine  lurking at the buffers can follow the train up the platform and stop at the shunt signal, this is separate to signal lever movements, but easily switched with cab control.

DCC solves the switching issue but the controls are so unwieldy compared to good DC Handhelds, Morley, OnTrack etc.  I unplug mine and plug them in to various sockets around the layout. 

So you sort of start to double the number of signals.

 1,  A Starter signal I want to route A, X and C to the FY controller for departing train

1a, A shunt signa/ arm l I want to route A, X and C to the Layout  controller for shunt to release incoming engine.  Etc,

It sort of falls between DC and DCC stools sort of needing DCC with lightweight hand controls, but they always seem to have two or four silly little knobs.  I would go cab control and keep signals and track power separate.

My loft railway had magnets under the brake vans and reed relays and relays which changed signals and switched on the power feeds to the section in advance and switched off the section in arrears  as the train advanced as long as the next section was vacant.  It was so horribly complicated I quickly realised I couldn't afford to build it, and it had massive authority problems when conflicting moves were needed.  I gave up.   Subsequent layouts have Cab control, each section has a double pole rotary switch  and can be fed from up to 5 plus off, (or 6) controllers

Works for me.

[t-b-g]

6 hours ago, DCB said:

It sounds both over complicated and lacking in flexibility.

If you are operating pre BR Blue era the engine which brings in the stock needs to be removed,

The section from buffer stops to platform starter  needs to change from one controller to another as soon as the train engine is clear of the signal so the incoming engine  lurking at the buffers can follow the train up the platform and stop at the shunt signal, this is separate to signal lever movements, but easily switched with cab control.

DCC solves the switching issue but the controls are so unwieldy compared to good DC Handhelds, Morley, OnTrack etc.  I unplug mine and plug them in to various sockets around the layout. 

So you sort of start to double the number of signals.

 1,  A Starter signal I want to route A, X and C to the FY controller for departing train

1a, A shunt signa/ arm l I want to route A, X and C to the Layout  controller for shunt to release incoming engine.  Etc,

It sort of falls between DC and DCC stools sort of needing DCC with lightweight hand controls, but they always seem to have two or four silly little knobs.  I would go cab control and keep signals and track power separate.

My loft railway had magnets under the brake vans and reed relays and relays which changed signals and switched on the power feeds to the section in advance and switched off the section in arrears  as the train advanced as long as the next section was vacant.  It was so horribly complicated I quickly realised I couldn't afford to build it, and it had massive authority problems when conflicting moves were needed.  I gave up.   Subsequent layouts have Cab control, each section has a double pole rotary switch  and can be fed from up to 5 plus off, (or 6) controllers

Works for me.

 

When I first saw and read about the wiring on Buckingham I thought the same.

 

Then I got to sit at the controls and operate it, initially when I visited the layout and then for the last 10 years with it at my place.

 

It is the best layout to operate that I have ever seen, mostly because of the lack of section switches. For the vast majority of moves, you set the points, set the signals and drive the trains. You don't have to think "have I switched that section on or off". If you pull the right levers for the move, the right controller is connected to the right track.

 

I used to wire my layouts with section switches and isolating switches so I have experience of both versions and to me, this is way ahead in terms of the experience of operating.

 

Rather than fall between DC and DCC, it combines the best features of both and does away with the less satisfactory aspects. The number of switches or buttons you need to press to drive a train is lower than either DC with section switches or DCC.

 

As for any lack of flexibility, I haven't found any yet. I can't think of a move that we can't  do but would like to.

[Nigelcliffe]

7 hours ago, DCB said:

 

DCC solves the switching issue but the controls are so unwieldy compared to good DC Handhelds, Morley, OnTrack etc.  I unplug mine and plug them in to various sockets around the layout. 

 

 

Not every DCC handset has more poorly positioned buttons than a 1990's video recorder controller.   

There are alternative designs.    One old minimalist design was called "Fred", originally a DIY item from the Fremo group, but later a commercial product from Uhlenbrock.   Works with LocoNet systems, so Uhlenbrock, Digitrax, Digikeijs, RocoZ21, etc...   I have a Fred, its really nice, and its frequently handed to visitors at shows because it's so simple.  

 

The first DCC layout I ever operated (approaching 20 years ago) used Fred throttles.   There were five locos in service at any time on the layout and five throttles.  Each throttle had a stuck-on label on the back, indicating which loco it was associated with.   If you wanted to change loco, you found the labelled throttle and plug it in, turned the speed knob and the loco moved.   If walking along the layout, set the loco running, unplug, walk along whilst loco runs, plug back in and resume control.    Operate signals and turnouts as normal, but no consideration needed on "electrical sections" or "isolating loco sections".     
The central system could be used to change which loco was associated with which Fred, should a loco need to be replaced in service, but that was pushed under the layout when operating, and not expected to be touched.  

 

 

- Nigel

 

 

 

[IanN]

I must agree with Tony regarding operation. I also have built and operated models that have the “traditional” approach of separate power, point and signal switches, and the “signalman & driver” approach. Personally, I find the latter much more enjoyable.

My current layout is an interpretation of a real location has four lines into the station, and will replicate the prototype’s signals. It uses two controllers, one switchable between up or down line, the other between down slow or carriage siding ( up loop) using centre off switches. These pairings are intended to minimise the risk of accidental collisions. This is because although points and signals are interlocked for departing,  the arrivals side, due to my omitting 40 or so levers for the route indicators, isn’t . Although not insurmountable, this would have increased the complexity of the interlocking considerably. I chose not to switch the power through the signals. DPCO switches are used for the levers, the second set of contacts being used for basic interlocking wherever possible. Aesthetically, not as nice as a proper lever frame, but cheaper and more robust. Isolating switches have been used on the platform roads as the train engine is trapped until the carriages are removed.

What I found to be a useful exercise was to document the generic movements I wanted to replicate. Then prioritise them eg How vital is it to have a train arrive at the same time as another departs? How many simultaneous movements can one person control? You will almost certainly need to use relays, and remember to document everything as you go!

All the best

[DCB]

1 hour ago, IanN said:

 

What I found to be a useful exercise was to document the generic movements I wanted to replicate. Then prioritise them eg How vital is it to have a train arrive at the same time as another departs? How many simultaneous movements can one person control? 

 

 

That is probably the key to deciding which system to go for, which movements, and add in How many operators, which simultaneous movements, and how many locos will be in use per session. The four platform terminus I operate and wired can have three simultaneous moves electrics wise, while  the track layout allows five.  For me it's the simultaneous moves which bring the layout alive. My inspiration was reading about Borchester.   I can bring a light engine up a platform following its train with furious activity, the platforms are either section 1 or 4 and Up main is Green so its 1+2+6 or  4+5+6  to Green then 1 or 4 to white as the loco enters section 2 or 5, flick off the isolator switch and power up white controller drive the light engine. However in practice no other movement can be made while this is in progress.  That engine could be any one of fifty, Green is the Up line connects to any one of 4 controllers. It's how I remember carriage shunting being done at Inverness.  Equally if Devizes Castle leaves for Paddington, it stays in the FY for a scale 6 or 8 hours before returning as I like to run trains basically from 6 am to Midnight.   I also like to load locos to the limit and to drive them up the gradients, ease off over the points etc.   Outside its one engine in steam, one DC control but any one of five controllers can run it, from 40 feet away in one case.  So its a case of deciding what suits you.  I'm miles away from being satisfied.. Maybe when DCC functionality matches it price, "Alexa Throttle one to Ragley Hall," we might get somewhere.

[Lacathedrale]

I disagree fundamentally about technology, @DCB - I my entire job is microservices, machine learning, etc. and I want NONE of that in my toy trains. After all, if a lever frame with microswitches and relays and accurately depict absolute block signal operation - why would you do anything else (that is, apart from the upfront but essentially one-off complexity of the wiring table and diagram)?

 

6 hours ago, t-b-g said:

As for any lack of flexibility, I haven't found any yet. I can't think of a move that we can't  do but would like to.

 

I wonder how much of this is to do with the operational patterns that are built-in to Buckingham, i.e. the fairly prescriptive list of train movements in the timetable which correlate to localised prototype practise? I can imagine if you were just 'playing trains' then you might be frustrated?

 

This is the signalling and DC block (not signaling block!) diagram I have dreamt up.

 

Notes

Blocks a, b, c and d are at the buffer ends.

Blocks x and y are short dead sections leading into the fiddle yard.

"BS" is Belle Sauvage controller, "FY" is the Fiddle Yard controller.

 

Parallel Moves

There are only two parallel moves:

1. Up Main main through up throat (vs) and into P3/4 (cg, dh) on BS
   + P1/2 (e, f) through down throat (rtw)  on FY
2. Up Main through up throat (vs) across throat crossover (j) and into P2 (bf) on BS
   + P1 (e) through down throat (rtw) on FY

Technically the loco pocket could be worket at the same time as an up train arrival but both would be dealt with by the single station operator, so these moves would not occur in parallel.

 

Levers and resultant energisation + routing

Lever 1 (Platform 1 Starter) powers E,R,T,W to FY

Lever 2 (Platform 2 Starter) powers F,J,R,T,W to FY

Lever 3 (Platform 3 Starter) powers G,S,T,W to FY

Lever 4 (Platform 4 Starter) powers H,S,T,W to FY

Lever 5 (Platform 1 Shunt) powers E,R,T,W to BS

Lever 6 (Platform 2 Shunt) powers F,J,R,T,W to BS

Lever 7 (Platform 3 Shunt) powers G,S,T,W to BS

Lever 8 (Platform 4 Shunt) powers H,S,T,W to BS

Lever 9 (Loco Shunt) powers I,R,T,W to BS

Lever 10 (Advanced Starter) powers Y to FY

Lever 18 (P2 Calling On) powers V,S,H to BS

Lever 19 (P3 Calling On) powers V,S,G to BS

Lever 20 (P4 Calling On) powers V,S,F to BS

Lever 21 (Down shunt signal) powers T + Rotary switch

Lever 22 (Platform 2 Home) powers V,S,R,F,J,B to BS

Lever 23 (Platform 3 Home) powers V,S,G,C to BS

Lever 24 (Platform 4 Home) powers V,S,H,D to BS

Lever 25 (Distant ) powers X to BS

 

Lever Notes

Levers 1-4 and 5-8 are essentially the same, the only difference is which controller they route power to.

Levers 18-20 and 22-24 are also essentially the same, the only difference is that the home signals power to the bufferstops, and the calling on signals stop short

 

Additional Switching:

One plunger per platform (ae, bf, cg, dh) as per @t-b-g's wiring diagram to allow the station controller to move a loco within platform limits.

Rotary switch enabled by Lever 21 which routes power to BS for the following sections depending on what the box communicates via hand signals with the driver

• Loco Route: R, I
• Plat 1: R, E
• Plat 2: R, J, F
• Plat 3: S, G
• Plat 4: S. H

Plan

I'm fairly certain to get my foot in the door these are the correct DC block sections, and so I can bond and isolate them as required physically while laying track, run droppers down to a terminal connector, and take it from there.

 

Wiring Diagram

Quite how to convert this into a wiring diagram I do not know...

 

Edited December 17, 2021 by Lacathedrale

[Lacathedrale]

Forgot to say, @IanN - that looks fantastic!

[t-b-g]

29 minutes ago, Lacathedrale said:

I disagree fundamentally about technology, @DCB - I my entire job is microservices, machine learning, etc. and I want NONE of that in my toy trains. After all, if a lever frame with microswitches and relays and accurately depict absolute block signal operation - why would you do anything else (that is, apart from the upfront but essentially one-off complexity of the wiring table and diagram)?

 

 

I wonder how much of this is to do with the operational patterns that are built-in to Buckingham, i.e. the fairly prescriptive list of train movements in the timetable which correlate to localised prototype practise? I can imagine if you were just 'playing trains' then you might be frustrated?

 

This is the signalling and DC block (not signaling block!) diagram I have dreamt up.

 

Notes

Blocks a, b, c and d are at the buffer ends.

Blocks x and y are short dead sections leading into the fiddle yard.

"BS" is Belle Sauvage controller, "FY" is the Fiddle Yard controller.

 

Parallel Moves

There are only two parallel moves:

1. Up Main main through up throat (vs) and into P3/4 (cg, dh) on BS
   + P1/2 (e, f) through down throat (rtw)  on FY
2. Up Main through up throat (vs) across throat crossover (j) and into P2 (bf) on BS
   + P1 (e) through down throat (rtw) on FY

Technically the loco pocket could be worket at the same time as an up train arrival but both would be dealt with by the single station operator, so these moves would not occur in parallel.

 

Levers and resultant energisation + routing

Lever 1 (Platform 1 Starter) powers E,R,T,W to FY

Lever 2 (Platform 2 Starter) powers F,J,R,T,W to FY

Lever 3 (Platform 3 Starter) powers G,S,T,W to FY

Lever 4 (Platform 4 Starter) powers H,S,T,W to FY

Lever 5 (Platform 1 Shunt) powers E,R,T,W to BS

Lever 6 (Platform 2 Shunt) powers F,J,R,T,W to BS

Lever 7 (Platform 3 Shunt) powers G,S,T,W to BS

Lever 8 (Platform 4 Shunt) powers H,S,T,W to BS

Lever 9 (Loco Shunt) powers I,R,T,W to BS

Lever 10 (Advanced Starter) powers Y to FY

Lever 18 (P2 Calling On) powers V,S,H to BS

Lever 19 (P3 Calling On) powers V,S,G to BS

Lever 20 (P4 Calling On) powers V,S,F to BS

Lever 21 (Down shunt signal) powers T + Rotary switch

Lever 22 (Platform 2 Home) powers V,S,R,F,J,B to BS

Lever 23 (Platform 3 Home) powers V,S,G,C to BS

Lever 24 (Platform 4 Home) powers V,S,H,D to BS

Lever 25 (Distant ) powers X to BS

 

Lever Notes

Levers 1-4 and 5-8 are essentially the same, the only difference is which controller they route power to.

Levers 18-20 and 22-24 are also essentially the same, the only difference is that the home signals power to the bufferstops, and the calling on signals stop short

 

Additional Switching:

One plunger per platform (ae, bf, cg, dh) as per @t-b-g's wiring diagram to allow the station controller to move a loco within platform limits.

Rotary switch enabled by Lever 21 which routes power to BS for the following sections depending on what the box communicates via hand signals with the driver

• Loco Route: R, I
• Plat 1: R, E
• Plat 2: R, J, F
• Plat 3: S, G
• Plat 4: S. H

Plan

I'm fairly certain to get my foot in the door these are the correct DC block sections, and so I can bond and isolate them as required physically while laying track, run droppers down to a terminal connector, and take it from there.

 

Wiring Diagram

Quite how to convert this into a wiring diagram I do not know...

 

 

I agree with you totally. I cannot understand whey people cram their layouts and locos full of complex electronics when all you really need is something that gives you plus or minus 12v and an on/off switch.

 

Your logic looks good. The only thing you have that varies from Buckingham is the rotary switch for 21. Buckingham has a signal arm for each platform road. The loco spur on Buckingham is simply switched by the point. It doesn't have a working signal, just dummy ground discs.

 

It is interesting that the Buckingham signalling was altered over the years and all the calling on and shunt arms were not there on the earlier version. I am not sure how that was operated but there must have been more isolating switches like there still are at Grandborough.

 

Parallel moves often happen at Buckingham. Once a train is set to depart and is being driven by the Grandborough operator, you can follow the train up the platform with the main Buckingham controller, while a second controller is used to move something in the shed or the yard. Or you can have trains arriving and departing while Buckingham 2 controller shunts the yard. My regular operators find that one operator driving one train at a time is usually enough to concentrate on but being able to switch the goods yards to a second controller when extra operators are available gives that flexibility. Trains arriving and departing at the same time is a regular feature of the operation even with just two operators.

 

I was bound to forget something in the video and a couple of things I should have pointed out come to mind. Firstly, the up line (departure) switched by the advanced starter signal 7 is normally live. It has no isolation. It doesn't need any but if you wanted to add some, a simple on/off switch could be fitted. The down line does have a switch, on the RH side of the panel, near the plug for the second controller. The outer home signal (21/22) does not do any electrical switching. So you can accept a train, bring it up to the home signal and isolate it with the switch. You can then complete any shunting or a conflicting departure move before you clear the signal and bring the train in.

 

If anybody can think of a move that you might want to do at a station that can't be done on Buckingham, I would be interested to hear it. I have given it some thought and not come up with any.

[RJS1977]

1 hour ago, t-b-g said:

 

I agree with you totally. I cannot understand whey people cram their layouts and locos full of complex electronics when all you really need is something that gives you plus or minus 12v and an on/off switch.

 

 

Absolutely! Not to mention the time spent trying to identify the number on a loco at the far end of the layout, and then scrolling through a list to find the same number (especially if those two activities require different pairs of glasses....)

[Lacathedrale]

I think the idea of maturing into this lever-frame block system may be a smart move - there's nothing stopping me hooking up standard SPDT switches to the terminal strip initially to validate everything works as intended, and only then replacing with relays and diode matrixes and rotary controllers

 

On my plan, lever 25 (and 99 which is functionally identical from a block perspective) sets the block on the up arrivals main (v) either dead or controlled by BS, so I can bring a train to the platform homes, and prototypically re-set them both and this will isolate the train while other, non-departure station duties are performed by the BS controller. I can't quite see where 7 is on Buckingham - maybe it's in the video? - but in terms of down departure main since I have no dedicated headshunt it must be switchable between both controllers as shunt moves and departure moves both use it.

 

  

1 minute ago, RJS1977 said:

 

Absolutely! Not to mention the time spent trying to identify the number on a loco at the far end of the layout, and then scrolling through a list to find the same number (especially if those two activities require different pairs of glasses....)

 

Amen.

 

Edited December 17, 2021 by Lacathedrale

[t-b-g]

26 minutes ago, Lacathedrale said:

I think the idea of maturing into this lever-frame block system may be a smart move - there's nothing stopping me hooking up standard SPDT switches to the terminal strip initially to validate everything works as intended, and only then replacing with relays and diode matrixes and rotary controllers

 

On my plan, lever 25 (and 99 which is functionally identical from a block perspective) sets the block on the up arrivals main (v) either dead or controlled by BS, so I can bring a train to the platform homes, and prototypically re-set them both and this will isolate the train while other, non-departure station duties are performed by the BS controller. I can't quite see where 7 is on Buckingham - maybe it's in the video? - but in terms of down departure main since I have no dedicated headshunt it must be switchable between both controllers as shunt moves and departure moves both use it.

 

  

 

Amen.

 

 

No 7 is round the corner on Buckingham, just at the point where the break is between the Buckingham and Grandborough sections is when everything is set back in the frames. It is equivalent to your signal 10 switching your yellow section. It does get a mention in the video.

[t-b-g]

6 hours ago, IanN said:

I must agree with Tony regarding operation. I also have built and operated models that have the “traditional” approach of separate power, point and signal switches, and the “signalman & driver” approach. Personally, I find the latter much more enjoyable.

My current layout is an interpretation of a real location has four lines into the station, and will replicate the prototype’s signals. It uses two controllers, one switchable between up or down line, the other between down slow or carriage siding ( up loop) using centre off switches. These pairings are intended to minimise the risk of accidental collisions. This is because although points and signals are interlocked for departing,  the arrivals side, due to my omitting 40 or so levers for the route indicators, isn’t . Although not insurmountable, this would have increased the complexity of the interlocking considerably. I chose not to switch the power through the signals. DPCO switches are used for the levers, the second set of contacts being used for basic interlocking wherever possible. Aesthetically, not as nice as a proper lever frame, but cheaper and more robust. Isolating switches have been used on the platform roads as the train engine is trapped until the carriages are removed.

What I found to be a useful exercise was to document the generic movements I wanted to replicate. Then prioritise them eg How vital is it to have a train arrive at the same time as another departs? How many simultaneous movements can one person control? You will almost certainly need to use relays, and remember to document everything as you go!

All the best

 

Now that does look like fun to operate!

[Pannier Tank]

3 hours ago, t-b-g said:

I cannot understand whey people cram their layouts and locos full of complex electronics when all you really need is something that gives you plus or minus 12v and an on/off switch.

 

The good thing about Model Railways is that there are so many fascinating aspects to it. I like to combine my interests in Electrical /Electronics and Computing with my Model Railways. At the same time, I can understand your pragmatic approach to Model Railway Electrics.

[t-b-g]

3 hours ago, Pannier Tank said:

 

The good thing about Model Railways is that there are so many fascinating aspects to it. I like to combine my interests in Electrical /Electronics and Computing with my Model Railways. At the same time, I can understand your pragmatic approach to Model Railway Electrics.

 

You are quite right and as a member of MERG and knowing some people for whom designing ever more technologically advanced ways of driving their trains is just as much a hobby as building model trains, I should have thought a bit more before I posted that.

 

When I wrote I don't understand why they do it, I should have put that I don't understand what they do.

 

It is very clever but so beyond my comprehension that if a layout with that sort of control system ever went wrong and I was the only person around to put it right, it might as well go on a bonfire.

 

When something goes wrong on Buckingham, which does happen with many hundreds of rather ancient soldered joints, I can usually go straight to the cause and fix it. 

 

 

[Pannier Tank]

10 hours ago, t-b-g said:

When I wrote I don't understand why they do it, I should have put that I don't understand what they do.

 

No problem.

 

10 hours ago, t-b-g said:

It is very clever but so beyond my comprehension that if a layout with that sort of control system ever went wrong and I was the only person around to put it right, it might as well go on a bonfire.

 

I am fortunate in a way, in that my son assisted me in designing the Arduino / MERG side of things.  There is a brief video on MERG showing my Moretonhampstead Signal Interlocking System.

 

I would imagine there was still a learning curve to Buckingham's control system, but no doubt, it gives you great satisfaction in keeping Buckingham running.

 

 

 

[IanN]

Hi William 

 

may I offer a couple of observations based purely on your block plan and notes. It’s quite possible other factors I’m unaware of will render them irrelevant.

 

1. power sections f & j always work together unless I have misread your notes. Could the duplication be removed and have these as a single block/section?

2. If points 11 are set for the crossing, then interlocking should prevent signals 1, 5, 9, 2 & 6 from being operated ( the line being blocked before the next signal (10). This would suggest that power sections r & t could be combined into a single block.

3. reference to lever 22 powering section r appears incorrect

4. I’d be inclined to extend t past shunt signal 21 towards signal 10. This would enable anything being shunted to remain under power until it is clear of the shunt signal. If this was continued all the way to signal 10, it would then be possible for section y to be commence immediately after the signal making w redundant 

5. Levers 18 & 20 appear to have the sections being powered transposed. Better to be aware before the wiring starts……

6. Signal 25. I think think this would be better as an Outer Home signal than the Distant. The distant would only be pulled if one of the three Homes was clear, and if sig 99 was also clear. Depending on location, sight lines and distances involved some location, such as Princes St, the  Homes giving access to the platforms weren’t supposed to be cleared until the arriving train was stopped at the outer home or passed it at walking pace.

Will moving the  signal levers result in signals changing on the layout, or are they just to supply power? Even if operating signals are intended later, it’s better to include the wiring from the outset, rather than trying to retrofit.

 

Will a ‘run on’ be require whereby a signal can be reset to danger after the train has passed, but the power supply after the signal is maintained so the train continues its way? Or are the distances on the layout sufficiently short that the train has been stopped/ runs out of track before the signals are set to danger again?

 

The P4 North London Group did a series of Building the Layout articles in Model Railway Constructor for their model of Bodmin. Two or three of those related to powering track through signals which you may find interesting if you can get a copy.They also covered interlocking and how to replicate it electrically. From memory, this was within the period 81-84. It’s a series that I’ve long thought should have been compiled into a single publication.

 

Cheers

Ian

Edited December 18, 2021 by IanN
Corrected time period for MRC articles.

[Lacathedrale]

@IanN thank you so much for taking the time to look over this with me. You are quite right about F and J - J was created as a split off of r, when I realised that if they were the same block I wouldn't be able to depart from P2 while there was an arrival into P3/4. I did not realise I could just merge with F - so that's perfect.

 

 

I have a nagging feeling that r needs to be isolated from t but I can't trace it out in my head, so maybe you're right there.

 

Thank you for the note on lever 18, 20 and 22.

 

Re: signal 25 - I'll put my thinking cap on. Basically, the main line beyond the home gantry and ground signal (w and v) is a single train length until it hits the FY, so levers 10, 25, 97 and 99 are beyond the layout and really just toggling power to the FY tracks. If for the sake of prototypical accurace we call 25 an outer home, I'll survive!

 

You make a good point about the length of t and signal 21, the ringed signals from the platforms power all of w, but then they are reset then the shunt signal only powers t. So, either the ground shunt signal needs to also power w, or like you said - extend t al the way around to W as there are (as far as I can see) no other conflicting moves.

 

I'm most definitely hoping to fit working signals. I think I'd like to experiment with wire-in-tube before going full electric. I guess that's where those relays come in useful?

[Lacathedrale]

This is the simplified block section layout, with thanks again to @IanN:

 

Simplified Blocking

 

Blocks W and T consolidated into R

Block J consolidated into F

 

Levers and resultant energisation + routing

Lever 1 (Platform 1 Starter) powers E,R, to FY

Lever 2 (Platform 2 Starter) powers F,R to FY

Lever 3 (Platform 3 Starter) powers G,S,R to FY

Lever 4 (Platform 4 Starter) powers H,S,R to FY

Lever 5 (Platform 1 Shunt) powers E,R,R to BS

Lever 6 (Platform 2 Shunt) powers F,J,R,R to BS

Lever 7 (Platform 3 Shunt) powers G,S,R to BS

Lever 8 (Platform 4 Shunt) powers H,S,R to BS

Lever 9 (Loco Shunt) powers I,R to BS

Lever 10 (Advanced Starter) powers Y to FY

Lever 18 (P2 Calling On) powers V,S,F to BS

Lever 19 (P3 Calling On) powers V,S,G to BS

Lever 20 (P4 Calling On) powers V,S,H to BS

Lever 21 (Down shunt signal) powers R + Rotary switch

Lever 22 (Platform 2 Home) powers V,S,F,B to BS

Lever 23 (Platform 3 Home) powers V,S,G,C to BS

Lever 24 (Platform 4 Home) powers V,S,H,D to BS

Lever 25 (Distant ) powers X to BS