Points Control Panel - Switches

[Canley Central]

Using on-off-on switch, leaving the switch in an "on" position, would this cause damage to the point motor and/or affect the charging of the CDU?

 

I'm building a Control Panel and I'm think the on-off-on switches are the way to go, but wonder whether you'd have to remember to put the switch back to the off position. But I'd very much like other idea's of doing it.

 

Ideally I'd like to have a switch and an LED to light up the track line that is open on the panel.

 

I've got all surface mount Peco point motors, the main two switches would fire 2 points together for opening up the line to the other platform. Another question then would be having LED's wired up to the switches that are getting power from a CDU  and one is not great a soldering

[Amand]

There's a variant of the on-off-on toggle switch that's biased towards the centre off position - it flicks momentarily to either of the "on" positions then returns to "off". However, it offers no indication as to which way the point is facing. 

 

Your second question would need a double pole version of the switch. One pole carries the power for the points, the other can carry a different voltage / current for indicator lamps.

 

The easiest solution is something like this

 

https://www.brimal.co.uk/points-motor-direction-switch-with-indicator-memory.html

 

expensive, but no soldering needed, instructions seem comprehensive. No direct connection with Brimal, but I have purchased from him before.

[Tricky Dicky]

When looking up switches that only stay momentarily on look for (on)-off-(on) in the description the brackets around the on indicate the action is only momentary. Personally I do not think it is helpful simply monitoring a switch position as it does not tell you if the point has actually moved. Using either an inbuilt switch in the point motor or a micro-switch attached to the point is more accurate but it does mean more wiring.

 

One possible solution to simply show which way the switch was moved is to use a on-off-on switch alongside a (on)-off-(on) switch mounting both close to each other the former for the LEDs  such that when you operate one switch you move the other.

 

Richard

[cliff park]

and in answer to your other question, yes it would effectively stop the CDU ever charging.

[regme]

I have done something similar to what you are after, however there is soldering involved, sorry you can stop reading now.  Anyway there are two options that I found that satisfied my limitations in understanding electronics and soldering ability. 

 

The first was there switches by this guy http://www3.sympatico.ca/kstapleton3/751D.HTM they come in kits or pre-made.  I went with the kits and had all sorts of greif especially with the soldering, the wires were too small.  Theses have the CDU built in and can run your LED's

 

The second involved a few more bits, but was easier to put together and understand what was going on, but there is a parts list.  You will need

• CDU (easy to make yourself) https://www.brian-lambert.co.uk/Electrical_Page_3.html#Bookmark8  This site is really good
• Memomentary (on)-off-(on) switch - to run the points
• DPDT Non-Latching Relay PCB Mount (HFD2/012-S-L2-D) - to run the LED's
• Power supply for LED
• Power supply for CDU
• Resistors for LED

So basically when I throw the switch it throws the point and changes the LED.  I have two bi-colour (reg/green) LED's per point (using Hornby points) to tell me which point is open and which is closed.

 

I was going to post a photo, but it's not pretty.

[Canley Central]

On 18/10/2019 at 23:46, Amand said:

There's a variant of the on-off-on toggle switch that's biased towards the centre off position - it flicks momentarily to either of the "on" positions then returns to "off". However, it offers no indication as to which way the point is facing. 

 

Your second question would need a double pole version of the switch. One pole carries the power for the points, the other can carry a different voltage / current for indicator lamps.

 

The easiest solution is something like this

 

https://www.brimal.co.uk/points-motor-direction-switch-with-indicator-memory.html

 

expensive, but no soldering needed, instructions seem comprehensive. No direct connection with Brimal, but I have purchased from him before.

The switches from Brimal make it look a great deal easier to make the panel I'd like. I'm just trying to work out if a CDU can still be wired in, or is needed at all, and whether I can change two points on the one switch to bring a line into operation on the other side of a platform?

[Sol]

A CDU or similar circuit protects the solenoid coil from burning out.

http://www.talkingelectronics.com/projects/CDU - overview/CDU - Overview.html

https://rail.felgall.com/ps.htm

 

[Il Grifone]

In answer to the original question, leaving the switch in the 'on' position would cause the point motor to rapidly burn out (unless there were some additional protection). In the case of the CDU it would prevent this from recharging.

[DCB]

If you want to leave the switches thrown and have LED indications then using stall motors instead of solenoids has to be the way to go. Use DPDT switches and use the second part of the switch to light the LEDs.    This has the potential to become a hobby in itself as you can get into having to use a diode matrix to light certain LEDs.  Personally I find LED indication to be more hassle than its worth, I just reset the route every time.

[Sol]

or use one of these http://www3.sympatico.ca/kstapleton3/751D.HTM

[Sol]

LED indication works perfectly for the crew on my layout to show status of main line & main station turnouts firstly on the station panel

   then on the wall panel .

Yes, a bit of wiring.

Edited December 3, 2019 by Sol

[michaelp]

Nice looking panel Sol

[sharris]

One way you could go, is to use DPDT (on)-off-(on) - (i.e. non latching) toggle switches. Use one pole of your switch to control the CDU, but use the other pole to control a simple memory device to your direction indicator LEDs. 

 

The memory device is called a bistable latch or flip-flop, and is most easily implemented by cross-coupling two NAND gates (google will instantly throw up appropriate circuits) - if you're not good at soldering, you might need to find a friend who is reasonable at it.  

 

The only caveat is that if you power down your system, the bistables will forget which way your points were set when last used, so when you start it up, you'll have to actively set up all the routes to reset them to the correct states. 

 

Edited December 3, 2019 by sharris

[Sol]

Or use one of these in conjunction with solenoids coils

http://www.heathcote-electronics.co.uk/point_indicator.html#POINT-INDICATOR-RELAY

[RAF96]

Just to clarify for the OP..

The points motor switching and the position indications are separate circuits.

 

The points motor switching (solenoid) is via a CDU to give oomph for multiple or sticky solenoids, using the quoted (ON)-OFF-(ON) toggle or other switching arrangements. Stall motor units are slightly but not overly different.

 

The indication of the selection is best gleaned from a switch at the points which tells when the point has moved to the selected position. Usually this is by way of a switch on the point motor (solenoid or stall type) or other micro switch arrangement operated by the point tie-bar.

 

You can rely upon the selection as your guide to routing but the ‘point has moved’ switch is a far better method.