leds on control panel

Post Reply
Posts: 2
Joined: Thu Mar 25, 2021 9:49 am

leds on control panel

Post by giddykippa »

hi everyone im completely new to model railways and at 56 im just starting my first layout which due to available room has to be marklin z gauge im building a 72" x 30" coffee table design my conundrum is the electrics all the marklin points work on a momentary pulse ie you press the button it sends pulse to move track you release button and that's it but i want to make my own control panel ive bought 0n/0ff/on momentary toggle switches and red and green leds i want to have the direction of track via points showing with either red or green leds the trouble is as its a momentary pulse the leds won't stay lit and im at a loss as to how to wire that up im guessing a relay might be needed but im absolutely useless with electronics and can't figure out how that would work i was hoping someone knowledgeable on here could guide me with a very simple wiring diagram and list of what parts i will need ie the relay ive tried google and youtube but can't find anything for marklin any help greatly appreciated
Posts: 19
Joined: Fri Mar 12, 2021 7:38 am

Re: leds on control panel

Post by SealionSteve »

Hi Paul

If you use double-pole/double throw (DPDT) switches you can achieve what you want to do. I'm not saying this is the best approach but it is fairly straightforward. My method means that the LEDs don't confirm that the point has actually been changed - you have to remember to push the momentary push-to-make switch as well as move the DPDT. For something more sophisticated you might well need relays which I think are pretty bulky, but I know little about. Something like an Arduino to control the point motors and LEDs would work better, as it could check that the point has been changed before lighting the LED, but it depends how comfortable you are with computers etc. Anyway, here is my suggestion using simple switches...

A DPDT switch has 6 terminals on it. These can be used in 2 sets of 3 to switch 2 separate circuit pairs, each of these circuits can be in "position 1", "position 2" or completely off (assuming you buy the type of DPDT switches with a central off position).

The idea is to use one set of three terminals to send a low DC voltage via a resistor to either of two LEDs on your control panel and to use the other set of three terminals to switch one side of a higher AC voltage via a "push to make" switch to the solenoid operating the point.
Slide1.JPG (104.04 KiB) Viewed 1085 times
Slide2.JPG (133.14 KiB) Viewed 1085 times
Slide3.JPG (70.35 KiB) Viewed 1085 times
A disadvantage might be the extra space needed on the panel as you need room for the DPDT switch, a push to make switch and the 2 LEDs for each point you want to control.

Hope that helps. I haven't used LEDs on my own layout, I just used the position of the levers on the DPDT switches to show which way the point was switched. At the time I hadn't worked out the above but your question made me start thinking again, and the LEDs would make the Control Panel a lot better! I can see a control panel re-build coming up....!
Posts: 1
Joined: Thu Jul 22, 2021 12:41 am

Re: leds on control panel

Post by Biggles »

Hi Paul,
Sorry this is a little late but I am new to the forum and have only just seen your post.

What a great response that was from Steve, but did you both know that there is a brilliant method of controlling points / turnouts by a single pole double throw switch, without the need for the push button switches?

It is all explained on a website run by a guy called Martin In Australia.

A small unit needs to be built for each point. It has two diodes and a capacitor and the unit lives under the board close to the point motor. I make my units up on a piece of screw terminal strip and I use a “three pole double throw” switch and use the other poles for track power switching and leds although Martin’s scheme powers the leds off the main point motor supply. In retrospect I should have done it his way!

Essentially the scheme makes up a a simple capacitor discharge unit for each point. It has the advantages of delivering a strong kick to the point motor and only needs a single wire plus earth to each point, thus simplifying the wiring. The components are very cheap on eBay or Amazon and easily available

I could try to explain it all, but the account that Martin writes on his website “Model Rail Musings” explains it elegantly and concisely so I can’t add anything to it.

Here is the url.

https://modelrailmusings.weebly.com/poi ... tches.html

This takes you straight to the piece on point motors and toggle switches. Do have a good look round the website. Martin has some other superb tips and has done some amazing modelling. Have a look at some of his layouts and his scenery animations.

I find that the circuit gives reliable point motor operation every time and is simple to build and install. My layout (under construction) is Hornby Dublo 3 rail, over 60 years old, and the points all change reliably and with a satisfying click. The point motors are rated 12-15v ac or dc, and I am using the 12v dc accessory output on an original Dublo controller to power them. No, I don’t use it for controlling trains! I use modern feedback controllers for that so I can get some decent slow running out of the old locos.

Good luck!

Post Reply