Route Setting and Train Detection

[St. Simon]

Hi,

 

One of the things I would like for my next layout is be able to have the control panel looking like a real power signal box panel and operate in the same way approximately.

 

One of the things I want is to show the track plan lit up as it would be on a real panel. So when no route is set, only the outline of the track plan would appear on the panel. When the route is set, the route would be lit up in white and when a train occupies that section, the section would be shown in red.

 

For the indications I would use bi-colour LED's and I was planning to use Heathcote Electronics Infrared train detection modules.

 

What I want to know, is the a way of wiring it up, so when I press select the route the LED's show white, but when the train is detected, the colour changes to Red. I think I'm right in thinking that if I just wired it up without any sort of cut out / cut in measure that both colours would be provided?

 

Thanks in advance!

 

Simon

[jdp298]

Best advice I can recommend is the way you'd eat an elephant: a little bit at a time.

 

If you can sort the points to give you indication of which way they're pointing, that'd be the first thing. Each turnout would then feed the length of track ahead of it to the next turnout, and so on and so forth. You'd have to decide which was the start point, and how to deal with facing points, but that basic premise is where I'd begin.

 

In parallel (activity, not electrically), work out how'd you'd get train detection for any given block of the railway. With these two squared away, bi-colour LEDs can be controlled, probably with the train detection taking priority over the route setting (or only showing provided it's on an active route? Or tri-colour LEDs with red for active route and yellow for block occupied but not on a route...?). This way you'd see what was occupied even if it wasn't on a route. All this is logically possible with 2 or 3 transistors each time. It's below even what I'd use a raspberry Pi for.

 

Finally, bi-colour LEDs don't show both colours if both anodes are enabled; sometimes that's how you get the third colour.

 

Hope that gives you somewhere to start, but it's not something I've tried myself. Good thought project though.

[St. Simon]

Hi,

 

So it sounds like the closest I can really get is to have two sets of LED's, one White and one Red and have them both showing if the route is set and occupied and then only the white showing if the route is set but not occupied?

 

Simons

[Gordon H]

The obvious combinations are 'Off' for no route, not occupied, Red for 'Occupied' whether route is set or not, and white for route set but not occupied.

For red/white/off indications I personally use a bi-colour LED from Rapid:

http://www.rapidonline.com/electronic-components/kingbright-led-bi-colour-red-white-3-65mm-80433

[uax6]

So you want to replicate an N-X panel?

 

Using bi-coloured LEDs is the right way to go, or use seperate white and red rectangular LEDs, pleaced either ontop of each other or side by side.

 

The biggest issue you will have is the detection of the trains! I have seen a way of doing proper track circuits, using a higher voltage across the rails, with the relays selected so that they will not operate until they recieve 14+ volts and are bridged by the wheels. I'll have a look to see if I can find the articles. The only problem i can see is that there were probably using GPO spec 3000 type relays, which are difficult to get hold of these days, although I'm sure that 24v octal relays can be 'adjusted'. Also each wheel will need a resistor across it to prevent a full short.

 

Then you can have the output of the relay wired to isolate the white LED's and turn on the red occupied leds.

 

As the trains clears a section you don't want the white LEDS to come on again, as you need to set the route for each train, so on the feed from the track relay that isolates the white leds, insert another relay that does has one contact that turns off the white leds, and another contact that 'self locks' the relay when the track relay operates it.

 

I would try and get hold of some drawings for N-X panels while on your apprenticeship, don't mention that they are model railway use, but for study use to allow you to expand your knowledge!

 

Andy g

[Suzie]

Simon

 

It really depends how big the layout is that you are trying to control. A small area with a single point can probably be done with a bit of hard wired logic, but anything more complex will be easiest to achieve with a computerised system like JMRI which has most of the logic you require built in just like the real thing. JMRI can be interfaced to a physical panel for input switches and indications. The nice thing about JMRI is it is free so you can try it out and see if it does what you want with no expense.

 

Detection can be done with Heathcote IRDOTs, and you can use either bi-colour/tri-colour LEDs on the panel if you are happy with red/yellow/green or you can use RGB LEDs and have any colour you like for the route set/occupied indications. Alternating two different coloured rectangular LEDs should give a perfectly acceptable display.

[Only-Me]

Ive created a mimic panel for Tormouth if you want to take a look... Automatic routing is a plan too but some way off!!

 

http://www.rmweb.co.uk/community/index.php?/topic/83532-tormouth/page-3&do=findComment&comment=1432647

[phil-b259]

Hi,

 

So it sounds like the closest I can really get is to have two sets of LED's, one White and one Red and have them both showing if the route is set and occupied and then only the white showing if the route is set but not occupied?

 

Simons

 

Thats how its done on a traditional NX panel (even in a 2005ish vintage one which uses SMD LED packages) although in many cases its not obvious as the lights are arranged so they both illuminate the same translucent bit of the panel

[St. Simon]

Simon

 

It really depends how big the layout is that you are trying to control. A small area with a single point can probably be done with a bit of hard wired logic, but anything more complex will be easiest to achieve with a computerised system like JMRI which has most of the logic you require built in just like the real thing. JMRI can be interfaced to a physical panel for input switches and indications. The nice thing about JMRI is it is free so you can try it out and see if it does what you want with no expense.

 

Detection can be done with Heathcote IRDOTs, and you can use either bi-colour/tri-colour LEDs on the panel if you are happy with red/yellow/green or you can use RGB LEDs and have any colour you like for the route set/occupied indications. Alternating two different coloured rectangular LEDs should give a perfectly acceptable display.

Hi,

 

It's only going to a small layout with a single platform, loop line and a couple of sidings, trying to get a track plan that allows me to concentrate on the details rather than how much is going on. I personally prefer hard wiring, but I will look at JMRI!

 

Thanks,

 

Simon

[michaelp]

If you were thinking about train detection modules this might be worth a look, fully programmable and reasonably priced too.

 

 

 

http://www.blocksignalling.co.uk/index.php/shop/product/view/2/15