Wiring Point Indicator Boards

[arliatna]

I??™m trying to build a control panel that includes LED??™s to show which way the route is set. What I??™d like is ??“ if points are set for straight running that route will show a green LED and the curve route will show a red LED, and if points are reversed the straight route will show a red LED and the curve route will show a green LED. I??™m using a mixture of Peco and Seep points with a point indicator board (from All Components), and Red and Green LED??™s. The track is Peco code 100 Insulfrog.

 

I understand the short leg of one LED (say Green) needs to be connected to the long leg of the other (say Red). Using two pairs of LED??™s so joined and connected to the PIB I can only get either both Green LED??™s or both Red LED??™s illuminated when I throw the point switch, which is obviously useless for route indicating. If I swap the PIB connection for one pair round I just get one or other Red LED illuminated when I throw the point switch.

 

Can anyone please advise (in simple terms as I??™m an electronic ignoramus) how these things need to be wired up to achieve my objective ?

[Grovenor]

The All Components website is completely lacking any info on their product, but what you want to achieve should be straightforward, do they provide instructions?

 

Assuming that the module provides output terminals to connect LEDs for both straight and curved positions then just connect the two, (one red and one green) that you want to be lit together in series to the appropriate two terminals. ie connect from the positive terminal of the board to the long lead on a green LED then from the short lead to the long lead of the red LED then from the short lead of the red LED back to the negative terminal. Do the same for the other pair of LEDs to the other two terminals. You should then get one red and one green lit in each position and can fit them to the panel appropriately. (This assumes series resistors for the LEDs are included on the board, if not you need to wire a resistor in series with each pair of LEDs.

If you need more detail tell us more about the board.

Regards

Keith

[naugytrax]

I don't know anything about the All Components devices, but they may be similar to the Point Indicator Boards marketed by Heathcote Electronics - see here: linkit

If that's true, the read and green LEDs in each pair should be connected in (reverse) parallel, not in series. I think that you have wired them in parallel, but it's not entirely clear.

Could you post a rough circuit diagram of how you made the connections? I believe I understand your first observation, but not what happened after you "swapped

the connections" for one pair.

[Grovenor]

I don't know anything about the All Components devices, but they may be similar to the Point Indicator Boards marketed by Heathcote Electronics - see here:

If this is correct then I auspect that having red and green LEds in parallel the green does not get enough voltage to light.

Try connecting both green LEDs in series across the output, if they light up OK then you can connect the two reds in series but with the opposite polarity.

Keith

[Guest RAFHAAA]

Use bi-colour (3-legged) LEDs (from Maplins). Connect the common legs to your aux feed neg via a 1k Ohm resistor each and the red/green legs via a Peco PL-13 switch attached to your point or point motor (or any other switch if your PM has them) back to a common positive. As said above you connect a red leg of one LED and a green leg of another together to get the green on straight / red on turnout and vice-versa effect.

If your LEDs are opposite polarity type (common anode vs common cathode) rewire accordingly.

For cross over loops you can link up 3 or 5 red/green LEDs to indicate the way on each track. I have a wiring diagram but its on the other pc which is in a 40 ft deep sea container on its way to Cyprus else I would post it to you via PM.

 

Rob

[Brian]

Hi

If you're using Bi Coloured LEDs then wire like below depending if they are common Anode (positive) or common Cathode (negative).

 

You can of course use single LEDs times 2 and wire them the same as the bi coloured ones

 

[Guest RAFHAAA]

Thanks Brian

A pic is worth a thousand words.

My diag showed several LEDs linked (as in across a junction) but the basics are there.

Rob

[arliatna]

Hey Guys,

Having just risen from my sick-bed (flu) I was amazed to find all the helpful replies waiting for me. It will take me a while to absorb all the helpful info you've so kindly provided, so it will probably be after Xmas before I can get round to trying out your suggestions (assuming I can understand it all). But for now, thanks again for the valued assistance. I'll report back when I can.

Merry Christmas to you all,

Alan

[arliatna]

I regret to say that despite all your advice I have failed to achieve the objective. Either I??™m even thicker than I thought or these Point Indicator Boards are not actually designed to do what I want (both options are quite likely !).

 

I set up a test rig as shown in diagram 1

PIB Setup Diagram 1.doc

 

In the first series of attempts, on the Normal route the short leg of the Green LED was wired to the long leg of the Red LED, and on the Reverse route the short leg of the Red LED was wired to the long leg of the Green LED. I think this means I wired them in series ?

I used different colour wires to link the LED??™s to the Point Indicator Board so I could follow what I was doing. These were :-

Normal Route ??“ long leg Green LED = red wire

Normal Route ??“ short leg Red LED = yellow wire

Reverse Route ??“ long leg Red LED = grey wire

Reverse Route ??“ short leg Green LED = blue wire

 

I tried attaching these wires to the PIB in various permutations with the following results :-

 

1) Red + Grey into PIB slot 1 and Yellow + Blue into PIB slot 2 caused both Green LEDs to light on Normal and nothing on Reverse

 

2) Blue + Grey into PIB slot 1 and Yellow + Red into PIB slot 2 gave nothing either route

 

3) Yellow + Grey into PIB slot 1 and Red + Blue into PIB slot 2 caused the Red and Green LED on Normal route to light when route set to Normal, and Red and Green LED on Reverse route to light when route set to reverse.

 

4) Yellow + Blue to PIB slot 1 and Red + Grey to PIB slot 2 gave nothing on Normal and both Green LEDs lit on Reverse.

 

I then rewired the LEDs (in series ?) ??“ see Diagram 2. PIB setup Diagram 2.doc

On Normal route I wired the short leg of Green Led to long leg of Red leg, with a Yellow wire to PIB ; and short leg of Red LED to long leg of Green LED, with Red wire to PIB. On Reverse route I wired short leg of Red LED to long leg of Green LED, with Blue wire to PIB ; and short leg of Green LED to long leg of Red LED, with Grey wire to PIB. This gave the following results when attached to PIB :-

 

1) Red + Grey to PIB slot 1 and Blue + Yellow to PIB slot 2 caused the Red LED on Normal route to light when route set to Normal , and the Red LED on Reverse to light when route set to reverse.

 

2) Red + Blue attached to PIB slot 1 and Grey + Yellow attached to PIB slot 2 caused both Green LEDs to light when route set to Normal, and both Red LEDs to light when route set to Reverse.

 

3) Red + Yellow attached to PIB slot 1 and Grey + Blue attached to PIB slot 2 gave nothing at all

 

4) Blue + Yellow attached to PIB slot 1 and Red + Grey attached to PIB slot 2 caused the Red LED on Normal route to light when route set to Normal , and the Red LED on Reverse to light when route set to reverse.

 

5) Grey + Yellow attached to PIB slot 1 and Blue + Red attached to PIB slot 2 caused both Red Leds to light when route set to Normal and both Green LEDs to light when route set to Reverse

 

If all this sounds very complicated then I found it so too! I am now totally befuddled, and suspect that these PIB??™s are only designed to illuminate one light according to which route is set, and not to give a positive indication of the route by showing a Green light for the route set and a Red light for the route not set. The supplier has not yet been able to show that what I want is feasible either.

 

Unless anyone has any other ideas I??™ll have to just use one light for each route. Thanks for all the help ??“ I feel I??™ve learned a bit from all your advice and useful links so this forum has done me some good.

 

Happy New Year all

Alan

[naugytrax]

Thanks for the diagram, Alan. This makes things clearer! Your diagram 1 shows the LED's in series, which is the way to go. Diagram 2 shows the LED's in parallel.

Wiring case 3) of diagram 1 is doing what you need, believe it or not! You just need to physically swap the red LED's on your control panel. The red LED which lights when the switch is in the "normal" position should be placed in the "reverse" path on your mimic diagram, and vice versa. Of course, you'll need to place extra wires between the red and green LED's of each pair - the short leg of a green LED can't be soldered directly to the long leg of its corresponding red LED, for example, because they will no longer be physically adjacent, but instead should be linked by a wire.

Good luck and Merry Christmas!

[naugytrax]

Here's a version of the original Diagram 1 which may help to explain what I just wrote! The added wires between the LED's are brown and magenta.

PIB swapped Diagram 1.doc

[Grovenor]

Nice to see from the test results that my earlier advice works, (diagram 1 case 3) and thanks to naugytrax for drawing it out properly.

Cheers and Happy Christmas.

Keith

[arliatna]

FANTASTIC ! It works ! I followed the revised diagram by Naugytrax and got the result I wanted, viz Green light on Normal route and Red light on Reverse route when points switched to Normal, and Red light on Normal route and Green light on Reverse route when points switched to Reverse.

Many thanks Humphrey, Keith and Rob, for all your helpful advice and pointers. I feel I've learned quite a bit from all this, for which I'm really grateful. I can now wire up the rest of the control panel.

Cheers guys,and a Happy New Year from a very appreciative,

Alan