operation of signals

[Steve Redford]

Just thought I would run this through your combined immense knowledge base!

 

I want to operate some points using a Hornby surface mounted motor and activate a signal to indicate the route direction of the point. Just to say that that if the point is set incorrectly it would show red etc. I have a DCC system and I am not using a Hornby accessory DCC decoder so they would be manually operated at the moment.

 

I intend to use lever micro switches on the point bar to operate the LED's on the signal ( red/green) etc - is this the best or only way to go about this on DCC. I also don't know how reliable they are ( micro switches) or how easy to fit.

[beast66606]

I hate signals which clear with the points I'm afraid, my advice would be to build a lever frame out of simple toggle switches and operate the points and signals from it, if you want the signals to clear with the points it could get quite messy as some signals will need more than one point setting a particular way, meaning you will need power routing to do it correctly.

[The Stationmaster]

I go with Beast on this. Simple toggle switches can achieve a lot but if you have signals with some sort of route indicator working in conjunction with the main signal head you will have to go a bit further and use relays or get into solid state circuits (relays are very simple to understand as they are in reality a switch and you can see how it works but they're not so easy to come across at bargain prices nowadays and they do take up space). But one big advantage of all of this is that the circuitry is very easy to understand once you've grasped the basics.

[Suzie]

If all you want is a simple red/green indication, it is easy if you have live frog points on DCC. For one signal just connect the green between one side of the DCC supply and the frog, and the red between the other DCC supply and the frog. If you have a second signal for the other route just wire it the other way.

 

If using LEDs for the signals you will need to protect them against reverse voltage with inverse parallel diodes.

 

 

 

 

Here are a couple of ways of doing it if you want to make searchlight signals with a single lens:-

 

 

 

 

 

 

Just substitute the bi-colour or tri-colour LEDs for a pair of discrete LEDs if you want a two-lens signal.

 

 

[RAF96]

You will probably find that the spring of the lever arm microswitch is powerfull enough to overcome the small mechanical resistance of a turnout operated by a surface mount point motor and spring the point back to a centre position.

 

I presume by surface mounted you mean the small motors like in the picture and not the older solenoid ones mounted top-side.

 

 

For a direct LED DCC indication without switches you can wire a 3-legged bi-colour LED across an insulated frog providing you are not using Hornby point clips. Centre wire goes via a 1K resistor and joins the inside rails of the straight/diverging routes and the other legs are wired to the left and right rails of the entry route. See picture.

 

 

Rob

[Steve Redford]

Thanks for the circuit diagrams - i will consider this route!

 

 

 

If all you want is a simple red/green indication, it is easy if you have live frog points on DCC. For one signal just connect the green between one side of the DCC supply and the frog, and the red between the other DCC supply and the frog. If you have a second signal for the other route just wire it the other way.

 

If using LEDs for the signals you will need to protect them against reverse voltage with inverse parallel diodes.

 

 

 

 

Here are a couple of ways of doing it if you want to make searchlight signals with a single lens:-

 

 

 

 

 

 

Just substitute the bi-colour or tri-colour LEDs for a pair of discrete LEDs if you want a two-lens signal.

 

 

[Steve Redford]

Yes - I am using those point motors with the Hornby point clips installed.

 

Thanks

 

 

You will probably find that the spring of the lever arm microswitch is powerfull enough to overcome the small mechanical resistance of a turnout operated by a surface mount point motor and spring the point back to a centre position.

 

I presume by surface mounted you mean the small motors like in the picture and not the older solenoid ones mounted top-side.

 

 

For a direct LED DCC indication without switches you can wire a 3-legged bi-colour LED across an insulated frog providing you are not using Hornby point clips. Centre wire goes via a 1K resistor and joins the inside rails of the straight/diverging routes and the other legs are wired to the left and right rails of the entry route. See picture.

 

 

Rob

[Steve Redford]

I had considered some bits and pieces from Heathcote electronics to 'solve' the problem - but for the simplicity of what I want to do and within the constraints of DCC I don't want the expense at the moment.

 

 

I go with Beast on this. Simple toggle switches can achieve a lot but if you have signals with some sort of route indicator working in conjunction with the main signal head you will have to go a bit further and use relays or get into solid state circuits (relays are very simple to understand as they are in reality a switch and you can see how it works but they're not so easy to come across at bargain prices nowadays and they do take up space). But one big advantage of all of this is that the circuitry is very easy to understand once you've grasped the basics.

[RAF96]

I go with Beast on this. Simple toggle switches can achieve a lot but if you have signals with some sort of route indicator working in conjunction with the main signal head you will have to go a bit further and use relays or get into solid state circuits (relays are very simple to understand as they are in reality a switch and you can see how it works but they're not so easy to come across at bargain prices nowadays and they do take up space). But one big advantage of all of this is that the circuitry is very easy to understand once you've grasped the basics.

 

I use bog standard 12v car relays - less than £2 at Maplins. Yes they do take up space unfortunately. PCB type relays are smaller but usually more expensive.

 

Robbie

[Brian]

I recognise those drawings. They were drawn originally by me! ;) Though one has been slightly modified.

 

<Snip>

Here are a couple of ways of doing it if you want to make searchlight signals with a single lens:-

 

Just substitute the bi-colour or tri-colour LEDs for a pair of discrete LEDs if you want a two-lens signal.

[Suzie]

I recognise those drawings. They were drawn originally by me! ;) Though one has been slightly modified.

 

 

 

They are both slight modifications of your original from another similar thread. Thank you for doing the hard bit!

[Brian]

Pleasure. :D

 

They are both slight modifications of your original from another similar thread. Thank you for doing the hard bit!

[43110andyb]

I go with Beast on this. Simple toggle switches can achieve a lot but if you have signals with some sort of route indicator working in conjunction with the main signal head you will have to go a bit further and use relays or get into solid state circuits (relays are very simple to understand as they are in reality a switch and you can see how it works but they're not so easy to come across at bargain prices nowadays and they do take up space). But one big advantage of all of this is that the circuitry is very easy to understand once you've grasped the basics.

 

I posted these circuits some time ago on the non DCC forum. Using relays to control the signal aspects and routes via point aux switches (as Beast says can get messy and I intend to use point relays as well to assist with route selection) The infra red sensor can be substituted for a simple push button switch to restore signal to red after being cleared. Hope it may be of use. ---Andy.

[Steve Redford]

Thanks for all your suggestions.

 

I have decided to go with a IR sensor and signal controllers from Heathcote Electronics.

 

Steve

[Steve Redford]

Actually I might go with the

TT301 TRAINTRONICS DCC 301 DCC & DCC FITTED – DCC DC INTERFACE DECODER CM-TT301