ThePurplePrimer Posted March 18, 2015 Share Posted March 18, 2015 Electrics is something that I don't know nearly enough about so I could do with some help please. I am planning my fiddle yard and am looking at using a diode matrix to fire solenoid point motors ( via CDU's ) I want to check that the turnouts have actually thrown properly and intend to use microswitches activated by the tiebar ( peco code 75 in the yard ) to detect if it has thrown properly rather than relying in the fact that the route has been set by the panel. I would like my panel to show the route with green non flashing leds ( all normal enough ) but what I would like to do is have the led flashing red dor a particular turnout ( rather than fixed green ) if the route has been set by the diode matrix but one of the turnouts didnt throw properly. Before I even try and work out how to wire this I need to know if such an led is available - ie two colour greeen and red but flashing if set to red - and if it is available is it reasonably priced ( I will need 30 of them ) Link to post Share on other sites More sharing options...
Tricky Dicky Posted March 19, 2015 Share Posted March 19, 2015 Probably not is the answer. You can get flashing LEDs which are usually 12v. The only other way I can see you achieving it with a single LED is use the three pin types which have a common anode and use an astable circuit such as one based on a 555 timer. You would only need one astable to flash all your red LEDS. The two pin bi-colour LEDs are actually two LEDs wired in reverse to one another and the colour lit dends on the direction of the current. Richard Link to post Share on other sites More sharing options...
spud Posted March 20, 2015 Share Posted March 20, 2015 Hi, there isnt anything like the device you asked about unfortunatley, and you could make a panel show red /green / flashing red but it would take some electronic logic to do it, and if its not your cup of tea, best avoided! one other way, which might be easier is to use the standard bi-colour led, with a bit of tolerance in your design. This led can indicate red or green, and if you power both the red and green, it will show an amber light! if that can be acceptable to your design, you might be able to wire it to show two colours for the point direction, and the third colour for a fault ??? hope this is some use! Link to post Share on other sites More sharing options...
Tricky Dicky Posted March 20, 2015 Share Posted March 20, 2015 Hi, one other way, which might be easier is to use the standard bi-colour led, with a bit of tolerance in your design. This led can indicate red or green, and if you power both the red and green, it will show an amber light! if that can be acceptable to your design, you might be able to wire it to show two colours for the point direction, and the third colour for a fault ??? hope this is some use! It cannot be done with a standard bi-colour LED as the two colours are connected in reverse to each other and therefore the current has to be reversed to display the other colour. To do what you want you need a tri-colour LED which either has a common anode or cathode. Richard Link to post Share on other sites More sharing options...
merlinb Posted March 24, 2015 Share Posted March 24, 2015 You can't buy LEDS like you describe, but you can buy Red/Greeen LEDs. You can also buy flashing LEDs. So let's get smart! Just put a flashing LED in series with the red half of a dual-colour LED (hide the flashing LED behind the panel). The red LED will then be forced to flash along with the flashing LED. (Yes it works- I checked!) You may want to adjust the resistors to suit your supply voltage / desired brightness, of course. Link to post Share on other sites More sharing options...
Grovenor Posted March 24, 2015 Share Posted March 24, 2015 Of course the microswitches will only control the green LEDs to show the route. To light the flashing red the way you want you will need another circuit that compares the position of the turnout with the position it is supposed to be for the route selected, which is not trivial. Regards Keith Link to post Share on other sites More sharing options...
RMweb Gold SHMD Posted March 24, 2015 RMweb Gold Share Posted March 24, 2015 You can't buy LEDS like you describe, but you can buy Red/Greeen LEDs. You can also buy flashing LEDs. So let's get smart! Just put a flashing LED in series with the red half of a dual-colour LED (hide the flashing LED behind the panel). The red LED will then be forced to flash along with the flashing LED. (Yes it works- I checked!) You may want to adjust the resistors to suit your supply voltage / desired brightness, of course. I like this and I've just realised that I have all the parts "fresh in stock" (hidden somewhere) so I think I will give this a whirl. Kev. Link to post Share on other sites More sharing options...
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