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How do I wire a simple track power shutoff with two switches in different locations?

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Posted by SeeYou190 on Sunday, August 27, 2023 11:15 PM

Dave, is this track a dead end spur?

-Kevin

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Posted by hon30critter on Sunday, August 27, 2023 10:50 PM

Greg has pointed out that my desire to have bi-colour LED indications on the track power shut off switches is a somewhat complicated request. That means that I will have to live with a simple 'LED on, LED off' indication. Unfortunately, I can't figure out how to wire that up.Dunce

I have attached a version of Kevin's power shutoff diagram. Please enlighten me.

Thanks,

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by hon30critter on Sunday, August 27, 2023 3:04 PM

Hi Greg,

Hmmm. Thanks for pointing that out. I told you I didn't know anything about electronics!!

If I use 1/2 of a DPDT switch, can I wire two single colour LEDs to simply go on and off in rhe same manner as the track power does? I will not be able to use the dwarf signals the way I wanted but I can live with that.

Thanks for sharing your expertise.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Sunday, August 27, 2023 1:42 PM

if there were a single dpdt switch, one pole could provide track power and the other pole provide + or - to a pair of LEDs.

but there are 2 switches wired in series.   if the first switch selects either + or -, the 2nd switch has no option.

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Sunday, August 27, 2023 1:09 PM

Hi Greg,

My thinking (dangerous, I know!) was that I could use a separate power source to provide + and - power to the LEDs through half of the DPDT switch using a separate power supply, not track power. I could tap into the Tortoise power for example. The other half of the switch would control the track power. Does that make sense?

The thought of getting into relays and power sensors worries me. 

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Sunday, August 27, 2023 8:40 AM

hon30critter
I want to have dwarf signals showing red/green indications beside the tracks.

the begging question is how many tracks?

it's not obvious that using DP switches in Kevin's (excellent) diagram is sufficient to provide power to either of 2 LEDs.  some logic seems needed to one LED "on" when the other is "off"

(it's not obvious if DP switches can can route +/- voltage to control either of 2 LEDs wired in parallel with opposite polarity)

i think Sheldon might suggest using a relay with multiple contacts to not only provide track power but also use a DP contact to provide power for green/red LEDs on both panels as well as a dwarf signals.

another approach is  to build a circuit that actually senses track power, regardless of the source.  that logic mentioned above would also be needed to control 2 LEDs

but things are getting complicated

 

 

 

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Sunday, August 27, 2023 7:37 AM

Hi Greg,

One thing that I haven't mentioned clearly is that I want to have dwarf signals showing red/green indications beside the tracks. I have some beautiful dwarf signals from Showcase Miniatures and it would be a sin to not make them useful.

I also do not want to use track power to run the LEDs. Don't ask me why.Tongue Tied

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
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  • From: lavale, md
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Posted by gregc on Sunday, August 27, 2023 6:58 AM

hon30critter
Since the power to the isolated track will be shut off on occassion, inserting an LED into the power feed wire won't work.

wouldn't it make sense that the track power LED is "on" when the track is powered?   i don't see a need for an LED indicating track power is off

and i don't see how a DPDT switch helps, since the track can be powered with the switch in either position.

since the one switch connects directly to the track, a track power LED could be wired to that switch.   it seems a separate wire is needed from track for the other switch panel

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Sunday, August 27, 2023 6:29 AM

Hi Greg,

The original question was about how to turn power to a track off using two switches, each with a 'green=on', 'red=off' indicator. Sheldon asked me to explain why I needed to have an LED lit when the power is off. I was trying to explain the fact that my wee brain has trouble understanding things if they are not obvious. I get confused easily.

I raised the subject of turnout indications in an attempt to give an example of what I need to see in order for me to easily understand what is happening. Trying to remember which route is the through route is difficult for me. Things will be much clearer for me with one route showing red and the other showing green.

I apologise for going off topic but it was the only way  I could think of to illustrate my mental challenges. I still have trouble telling right from left!

Sorry about the confusion.

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Sunday, August 27, 2023 4:51 AM

hon30critter
figure out how to be able to shut off track power using two switches,

hon30critter
I know that wire runs from turnout switch #1 post #2 on the north panel to turnout switch #1 post #3 on the south panel.

i thought you wanted to "power" a single track from 2 different switches.   

now you're discussing controlling "turnouts" from different positions? if so, what type switch machines?

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Saturday, August 26, 2023 9:21 PM

Hi again Sheldon,

Thank you for taking an interest in my project.

Here is an example of one of the control panels as it currently sits. I'm still playing with the uncoupler locations. The working area of the panel will be 6" x 12" +-. The squares represent the size of the switch bodies and the circles are 3mm LEDs. Most of the LEDs will be bi-colour red/green. The uncoupler LEDs will be blue only.

The big question is why do I need redundant LEDs? The answer is simple. I can't remember which is the through route and which is the diverging route. Call me stupid if you will, but if I can't see which actual track the turnout is set for, I'm going to screw things up. Each turnout will have two bi-colour LEDs, one for each exit route. If the indication on one track is green then obviously that will be the route that the locomotive follows, and if the indication is red, either the locomotive is not going to take that route or more importantly, it will derail at the turnout if it is running against the red indicator. 

I am going to do the same thing with the power shutoff tracks. If the LED is green then the track has power. If it is red, the track is dead. Redundant, yes, but it is also bullet proof, at least theoretically. I need bullet proof! I also want to put dwarf signals indicating the power status. Not prototypical but cool looking none the less.

The only exception will be the uncouplers. They will have a blue LED only to show when the uncoupler is set to work. The Rapido uncouplers have a blue LED that shines up between the ties directly over the uncoupler.

I appreciate your offer to show me how to simplify the wiring, but I feel quite strongly that it is more important for me to be able to understand the wiring based on what I know currently. I have enough to figure out as is without trying to learn new electrical theory. I have colour coded all the wiring, so if I am looking at yellow wire #T1-2, I know that wire runs from turnout switch #1 post #2 on the north panel to turnout switch #1 post #3 on the south panel. Yes, it will take a lot of wire but I'm pretty sure the layout won't collapse under the weight.

Please let me know what you think. You can even tell me what you think about me being a rather dumb electronic dinosaur!Smile, Wink & Grin

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by ATLANTIC CENTRAL on Saturday, August 26, 2023 6:05 PM

Dave, are there other controls on these panels?

Why do you need a light to tell you something is off? I the indicator light is off, the power is off?

I can show how to do this in a more "refined" way, but it is not easily explained in works or even a real simple diagram (which I do not know how to quickly draw "electronically" and post). 

I studied CADD to decades ago but ended up never using it. I forgot all that and never cared to learn any of the other "drawing" programs.

But if I understand a little better everything you want to do, I can draw a drawing and get it to you.

To do things similar to what you are asking I don't use toggle switches at all, I use lighted pushbuttons. And my controls can have as many multiple locations around the layout as you want. 

Examples: All my turnouts are controlled locally and ona dispatchers panel. LED's in the pushbutton show the route selected, the postion of each individual turnout.

The buttons that assign throttles to bocks (I run DC) typically are at three locations, each end of the block and on the dispatchers panel. 

When you push a button and change the status of a section of track, the LED indicators change at all the locations.

And becasue of how I do this it takes ver few wires out to the various locations.

Sheldon  

    

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Posted by hon30critter on Saturday, August 26, 2023 2:45 PM

Hi again Kevin and gang,

I want to have three LEDs in the circuit: one beside the isolated track and one beside each switch on the panels, and I want to have  them display a red (off) - green (on) indication. Since the power to the isolated track will be shut off on occassion, inserting an LED into the power feed wire won't work. I could get an 'on' indication but the LED would not be lit with the track power off. If I use a DPDT switch, it would seem that I can set up a separate circuit through 1/2 of the switch strictly for providing +- power to the LEDs? Does that make sense?

Thanks,

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
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Posted by SeeYou190 on Saturday, August 26, 2023 8:36 AM

hon30critter
What type of toggle switches are those, i.e. 'on-on'?

Yes, Single Pole Double Throw (SPDT) On-On switches.

hon30critter
I assume that the orange box is the Command Station.

Well, like in all my drawings it is a Troller power pack, but your command station is wired in the same, so... yes.

Laugh

NVSRR
Its is basically identical to a  three way switch set up in a house.

Yes, schematically it is exactly the same circuit.

NVSRR
So to make it easy.  A typical 3 way light switch will work just as well as a spdt switch.

Yes, 3-Way light switches will work.

I do not like using household wiring control devices for model railroads. They are difficult to mount in a panel, and if you use the electrical box as a mount they take up a tremendous amount of space.

NVSRR
The switch is an on off type because that is what the light switches are.

Not really. 

Household lighting control devices:

Single Pole: On-Off, SPST switch

3-Way: On-On SPDT switch

4-Way: On-On DPDT Reversing switch

-Kevin

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Posted by NVSRR on Saturday, August 26, 2023 7:04 AM

Its is basically identical to a  three way switch set up in a house.   Say a 2 light in a hallway with a switch at each end.   So to make it easy.  A typical 3 way light switch will work just as well as a spdt switch. So the switch is an on off Type.  Cause that is what the light switch is are.   The orange box is your power source.   

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A realist sees a frieght train

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Posted by hon30critter on Saturday, August 26, 2023 12:23 AM

Hi Kevin,

I have a couple of questions.

What type of toggle switches are those, i.e. 'on-on'?

I assume that the orange box is the Command Station.

Thanks. I really appreciate your help!

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
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Posted by SeeYou190 on Saturday, August 26, 2023 12:09 AM

I hope the drawing makes sense.

You can do it with a pair of SPDT toggle switches.

With this arrangement, the position of the toggle does not indicate if the track is on or off.

If the track is on, changing either toggle turns it off, likewise, if the track is off, changing either toggle will turn it on.

-Kevin

Living the dream.

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Posted by hon30critter on Friday, August 25, 2023 11:48 PM

Hi Sheldon,

Here is the situation. I am building a free standing 5"4" x 12' layout using DCC. I have mobility issues so I want to be able to operate the entire layout from one side or the other. Let's refer to them as being the north side and the south side. In other words, I don't want to have to walk from one side of the layout to the other to get access to a control panel. To that end, there will be matching control panels on both the north side and the south side of the layout.

I want to be able to shut off power to several tracks, and I want to be able to shut the power off to each track from either the north side control panels or the south side panels. Therefore,  I need to wire two toggle switches for each section of isolated track, and I have to do it so that either switch can turn the power off or on regardless of the position of the other switch.

I think I need something similar to the setup for using two toggle switches to control one Tortoise. I can post that diagram tomorrow. The difference will be that the Tortoise system keeps power on at all times and just reverses the polarity, whereas the power shutoff system has to be able to turn the power on or off from either switch.

Sorry if this explanation is a bit long.

Thanks for your help.

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
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Posted by ATLANTIC CENTRAL on Friday, August 25, 2023 11:03 PM

Dave, need a ittle better understanding of what you want to do? Do you use DCC or DC?

Sheldon

    

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How do I wire a simple track power shutoff with two switches in different locations?
Posted by hon30critter on Friday, August 25, 2023 10:16 PM

I have spent the last three hours trying to figure out how to be able to shut off track power using two switches, one on either side of the layout. I haven't had any luck! For all you electronic gurus out there, what type of switches do I need and how do I wire them?

I know how to wire twin switches for Tortoises but that circuit doesn't work because all the switches do is reverse the polarity. The power is always on.

Help!

Cheers!!

Dave

 

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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