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

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  • From: Bradford, Ontario
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Posted by hon30critter on Thursday, August 31, 2023 2:55 AM

maxman
I actually did read all the preceeding posts.  I was just confused by all the diagrams and some of the other non-relevent info.

Hello maxman,

I'm sorry that my feeble attempts to explain my situation confused you. I tried to make the track and wiring diagrams as clear as I could.

Bottom line is I don't want multiple locomotives parked on the layout with power on. 

I have noticed that the comments in this thread have taken on a wee bit of a sharp edge. Let's not go there please.

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 hon30critter on Saturday, September 9, 2023 9:17 PM

After much thinking about the spur shutoff circuits, I realized that the isolation circuits didn't have any LED route indicators on the control panels. They only had dwarf signals to show which way the turnouts were thrown, and in several cases the dwarf signals would have pointed away from where I will be seated when operating. This plan solves that problem:

 

This has the added benefit of allowing me to run all of the Tortoises on 18 volts. With the previous shutoff circuit I would have to supply the spur Tortoises with 12 volts because there was only one LED in the circuit vs six LEDs in all the other Tortoise circuits. I have an 18v 2A power supply on order so I will be able to run all of the Tortoises off of one power supply.

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 gmpullman on Saturday, September 9, 2023 11:11 PM

I think that wire toward the upper right might have to be eliminated if I'm not mistaken, Dave.

 Dave_Wire by Edmund, on Flickr

It is effectively bypassing the LED assemblies. 

I have a few instances where several LEDs are in series with my Tortoises. So far (25 years) no problems. Occasionally I'll get a dud LED that blows prematurely but this has been rare.

Good Luck, Ed

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Posted by hon30critter on Sunday, September 10, 2023 1:31 AM

gmpullman
I think that wire toward the upper right might have to be eliminated if I'm not mistaken,

Hi Ed,

Thanks for pointing that out. I made the same mistake in the other Tortoise wiring diagram too.Dunce

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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  • From: lavale, md
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Posted by gregc on Sunday, September 10, 2023 6:15 AM

don't the spur contacts need to provide power to one or the other spur track rails?

and isn't the source of track power from the preceeding turnout spur contact?

the posted drawing would be for the lead turnout in the ladder and it's output would go to the next turnout tortise in the ladder

greg - Philadelphia & Reading / Reading

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Posted by ATLANTIC CENTRAL on Sunday, September 10, 2023 9:05 AM

gregc

don't the spur contacts need to provide power to one or the other spur track rails?

and isn't the source of track power from the preceeding turnout spur contact?

the posted drawing would be for the lead turnout in the ladder and it's output would go to the next turnout tortise in the ladder

 

No, since Dave decided that the one more complex siding can just all be killed by the first turnout, each siding can get its source from the main DCC bus, and it only need to kill one rail.

As for indicators, the status of the track is indicated by the turnout position, I don't see the need for more lights.

I do this on my layout and this is why I like the lighted push buttons. To over simplify a bit, if the button for a route is lighted, it is powered. If the light is off the turnout is not aligned and trhe track is dead. 

Sheldon 

    

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Posted by gregc on Sunday, September 10, 2023 9:34 AM

ATLANTIC CENTRAL
No, since Dave decided that the one more complex siding can just all be killed by the first turnout, each siding can get its source from the main DCC bus, and it only need to kill one rail.

not talking about powering both rails.

doesn't each tortoise need to supply power to either the diverging and non-diverging paths when it receives power from the preceeding tortoise?

hopefully the following makes things clearer.  tracks labeled with numbers and tortoise switch machines with letters.

one set of SPDT contacts is labeled for when the machine is thrown (reverse), close (normal) and common.  the contacts on each machine indicate to which track or machine it is connected to.  the "+' on C mean track power.  assume only tracks 3-6 are power routed.

                   J     I     H
 7_______________________________________________
                   \     \     \
 6__________________\ G   \     \
                     \
 5____________________\ F
                       \
 4__________________    \
                    \ E  \
 3___________________\____\ D
                           \
 2__________________________\ C
         /                   \
 1______/_____________________\ B
                               \

      T  C  C
      r  l  o
      o  o  m

 G    6  _  F
 F    5  G  D
 E    3  4  D
 D    E  F  C
 C    _  D  +

greg - Philadelphia & Reading / Reading

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Posted by hon30critter on Sunday, September 10, 2023 9:55 AM

gregc
doesn't each tortoise need to supply power to both the diverging and non-diverging paths

Hi Greg,

Yes, the Tortoise has to provide power to both the spur and the through track. In my diagram, when the Tortoise is thrown for the through track the spur will not have power. When the Tortoise is thrown for the spur, the contacts on the left side of the Tortoise will connect the power to the + (red) rail. The - (black) rail will always have power.

To move a locomotive onto the spur I will select the spur route (sorry if that is too obvious). Once the locomotive is on the spur and doesn't have any other switching duties to perform, I will switch the turnout back to the through route and the power will be cut off to the spur.

The lights on the panels and the dwarf signal will show red when the spur is not powered.

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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  • From: Maryland
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Posted by ATLANTIC CENTRAL on Sunday, September 10, 2023 12:24 PM

gregc

 

 
ATLANTIC CENTRAL
No, since Dave decided that the one more complex siding can just all be killed by the first turnout, each siding can get its source from the main DCC bus, and it only need to kill one rail.

 

not talking about powering both rails.

doesn't each tortoise need to supply power to either the diverging and non-diverging paths when it receives power from the preceeding tortoise?

hopefully the following makes things clearer.  tracks labeled with numbers and tortoise switch machines with letters.

one set of SPDT contacts is labeled for when the machine is thrown (reverse), close (normal) and common.  the contacts on each machine indicate to which track or machine it is connected to.  the "+' on C mean track power.  assume only tracks 3-6 are power routed.

                   J     I     H
 7_______________________________________________
                   \     \     \
 6__________________\ G   \     \
                     \
 5____________________\ F
                       \
 4__________________    \
                    \ E  \
 3___________________\____\ D
                           \
 2__________________________\ C
         /                   \
 1______/_____________________\ B
                               \

      T  C  C
      r  l  o
      o  o  m

 G    6  _  F
 F    5  G  D
 E    3  4  D
 D    E  F  C
 C    _  D  +
 

No, if a given turnout is set to the siding it will be on, When the turnout is not set to the siding it will be off. The status of the other turnouts has no effect. The ladder track will always be completely hot.

I always have a hard time understanding your typed drawings.

The diagram you have above is for the big yard, not the original switching area. Dave has taken down that diagram at the beginning of the thread that showed the industrial area originally talked about. 

I have not analyzed the big yard but similar rules apply.

If Dave wants the yard to work that way as well, I will take a look. 

Sheldon

 

    

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Posted by gregc on Sunday, September 10, 2023 12:52 PM

ATLANTIC CENTRAL
The diagram you have above is for the big yard, not the original switching area.

same concept

ATLANTIC CENTRAL
No, if a given turnout is set to the siding it will be on, When the turnout is not set to the siding it will be off. The status of the other turnouts has no effect. The ladder track will always be completely hot.

doesn't that mean more than one spur can be powered at a time?

i thought he just wanted to power one spur?

greg - Philadelphia & Reading / Reading

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Posted by ATLANTIC CENTRAL on Sunday, September 10, 2023 2:11 PM

gregc

 

 
ATLANTIC CENTRAL
The diagram you have above is for the big yard, not the original switching area.

 

same concept

 

 
ATLANTIC CENTRAL
No, if a given turnout is set to the siding it will be on, When the turnout is not set to the siding it will be off. The status of the other turnouts has no effect. The ladder track will always be completely hot.

 

doesn't that mean more than one spur can be powered at a time?

i thought he just wanted to power one spur?

 

Dave never made that a requirement, you assumed that fact. Based on the track arrangement it is unlikely but would have no ill effects since he uses DCC.

Referring only to the originally discussed industrial area, because I have not analyized the large yard yet, the theory is you pull the loco into the stub end siding and throw the turnout back to the main route to kill the siding.

WHY would you re-align THAT turnout to the stub unless you planned to move that loco?

I see no need for complex interlocking here?

Sheldon

    

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Posted by ATLANTIC CENTRAL on Sunday, September 10, 2023 2:13 PM

As for the big yard, a very quick look suggests most of it could be handled the same way with no problems.

I would need to ask Dave a few questions about operational requirements to suggest a detailed control power plan.

Sheldon

    

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Posted by gregc on Sunday, September 10, 2023 5:46 PM

ATLANTIC CENTRAL
WHY would you re-align THAT turnout to the stub unless you planned to move that loco?

huh?

ATLANTIC CENTRAL
I see no need for complex interlocking here?

you think this is complex ?

ATLANTIC CENTRAL
As for the big yard, a very quick look suggests most of it could be handled the same way with no problems.

did you notice the E turnout serving 2 spurs?

greg - Philadelphia & Reading / Reading

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Posted by ATLANTIC CENTRAL on Sunday, September 10, 2023 6:02 PM

gregc

 

 
ATLANTIC CENTRAL
WHY would you re-align THAT turnout to the stub unless you planned to move that loco?

 

huh?

 

 
ATLANTIC CENTRAL
As for the big yard, a very quick look suggests most of it could be handled the same way with no problems.

 

did you notice the E turnout serving 2 spurs?

 

Again, I have not fully evaluated the big yard and don't plan to unless Dave asks for such help. Yes I saw it, and lots of other aspects that may require a feed thru from additional turnouts. But right now I'm not drawing any diagrams or writing any long explainations. Did you miss the part where I said "most" of the big yard can be handled the same way?

And again, I see no need for the original industrial area that was the topic of this thread to have any feed thru from other turnouts or any sort of interlocking.

In my opinion, you are making this more complex than it needs to be for Dave's purposes.

Sheldon

    

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Posted by hon30critter on Sunday, September 10, 2023 10:28 PM

Hi Sheldon and Greg,

Just to clarify, I only want to shut the power off to the spurs in the industrial area and the tracks in the service area that lead into the engine shop and the paint shop. I had originally thought about killing the power in the yard tracks too, but I have changed my mind. I don't plan on parking locomotives on the yard tracks.

As far as operations go, that is something that I am not too familiar with. When I started the layout my primary goal was to just run trains. As the plan developed I started to see lots of opportunities for switching, but I haven't given a lot of thought to creating proper operating sessions. I've never participated in an operating session. I have some learning to do.

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
    July 2006
  • From: Bradford, Ontario
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Posted by hon30critter on Monday, September 11, 2023 12:11 AM

ATLANTIC CENTRAL
I see no need for complex interlocking here?

I agree. The industrial spurs will be controlled individually.

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
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Monday, September 11, 2023 6:32 AM

ATLANTIC CENTRAL
I see no need for complex interlocking here?

but it is worth understanding, even if not used

routing power thru preceeding tortoise machines is not complex (nor an interlocking).

i hope your statement doesn't scare modelers away from considering this approach which i'm sure is fairly common

hon30critter
I think I need something similar to the setup for using two toggle switches to control one Tortoise. I can post that diagram tomorrow.

i understand, this is not unnecessary for "Dave's puposes" but i don't believe it is beyond his capabilites or level of understanding, nor the understanding of many modelers.   it is the same concept Dave is using to control turnouts using multiple switches in series

 

the yard is conventional and doesn't require much analysis.   i made some simple assumptions.   the E turnout is a minor complication that demonstrates how easily power routing can handle it.

hon30critter
I also want to put dwarf signals indicating the power status.

Dave didn't have a rigid set of requirements.  he was willing to consider and accept your suggestion for the sake of simplicity, which i agree with.

but not all his requests were fullfilled.  I understand his acceptance of this limitation.   it could be addressed with a variety of less simple approaches

3132

greg - Philadelphia & Reading / Reading

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Posted by ATLANTIC CENTRAL on Monday, September 11, 2023 3:14 PM

gregc

 

 
ATLANTIC CENTRAL
I see no need for complex interlocking here?

 

but it is worth understanding, even if not used

routing power thru preceeding tortoise machines is not complex (nor an interlocking).

i hope your statement doesn't scare modelers away from considering this approach which i'm sure is fairly common

 

 
hon30critter
I think I need something similar to the setup for using two toggle switches to control one Tortoise. I can post that diagram tomorrow.

 

i understand, this is not unnecessary for "Dave's puposes" but i don't believe it is beyond his capabilites or level of understanding, nor the understanding of many modelers.   it is the same concept Dave is using to control turnouts using multiple switches in series

 

the yard is conventional and doesn't require much analysis.   i made some simple assumptions.   the E turnout is a minor complication that demonstrates how easily power routing can handle it.

 

 
hon30critter
I also want to put dwarf signals indicating the power status.

 

Dave didn't have a rigid set of requirements.  he was willing to consider and accept your suggestion for the sake of simplicity, which i agree with.

but not all his requests were fullfilled.  I understand his acceptance of this limitation.   it could be addressed with a variety of less simple approaches

3132

 

Greg, I'm not disagreeing with any of that, my whole control system is based on the concept that turnout position routes power, which with DC control reduces the number of "blocks" that need to be assigned by half, sometimes more.

I am happy to help others when and where I can, but right now I don't have the time for long theoretical engineering discussions. 

And I am often confused at first by your ability to invent new problems to be solved.

The "but what if someone wants to..." questions are endless.....

Sheldon

    

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Posted by hon30critter on Thursday, September 14, 2023 9:46 PM

So just when everybody thought that we had bashed this topic to death, I decided that I couldn't resist adding some more complexity to it.

Sheldon's circuit did everything I wanted it to do, but it didn't address one issue that personally bugs the heck out of me (no, that's not Greg's questionsSmile, Wink & Grin). IMHO, most LEDs are too bright to the point of being painful to look at, and they can leave spots before your eyes. Also, in many cases, one colour will be much brighter than the other.

CharlieM from Colorado pointed out a solution that solves the brightness issue. The diagram in my previous post cannot use resistors to dim the LEDs because the insertion of resistors into the motor drive circuit would slow the motor down significantly. Also, if you are using a bi-colour 2 pin LED, the brightness of the colours may still be different. What is needed are 3 pin R/G LEDs with different resistors for each of the colours. The polarity of the LEDs will still be determined by Tortoise contacts #1 and #8 but they will be powered directly from the 12v power supply and not through the Tortoise motor power. I have attached a wiring diagram. Note that you will have to experiment with the resistor values. The ones I have shown may be too low to have the proper effect.

Here is a link to the thread where Charlie posted his explanation:

https://cs.trains.com/mrr/f/11/p/70182/3463815.aspx#3463815

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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