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Cross-Over Wiring Conundrum

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Cross-Over Wiring Conundrum
Posted by Anonymous on Tuesday, July 22, 2003 9:31 PM
OK, I need some help.

I've built a 44" x 72" (3' 8" x 72") layout that sits on top of my dining room table. It consists of two concentric ovals of track. On one side, there are 4 022 switches set up as two crossovers: one crosses over from the outside loop to the inner loop and the other one goes from the inner to the outer. The layout is built in two halves.

When I wired this up, I split the loops up 4 blocks. Each loop on a half is one block. The way it's constructed, each switch is in a separate block.

Today, I attempted to perform, for the first time, a cross-over with two locomotives on the layout simultaneously. This didn't work the way I envisioned it.

In order for the cross-over to work, I need to power a total of three blocks from the cab that controls the train I want to move. The problem is that the other train has to be occupying one of these blocks, which means that a collision is all but certain.

Let's consider the cross-over from the outer to the inner loop. This is composed of two right-hand turnouts. There's really only two ways the switches can be thrown: either both are straight through, or both are thrown to the alternate path.

Thinking about the problem, I realized that I need to electrically isolate the turnout on the inner loop from the rest of its block. What I'm seeing in my head is a simple toggle switch (2 positions only) which, when thrown in one position, makes the turnout act the way it does now, and, when thrown in the other position, makes it act like a part of the outer loop block (the one that the train is leaving). This way, I have to toggle this switch & set outer loop block on one side & the innner loop block on the other to the same cab.

I then need to do something similar on the other side, only on this side, I'm controlling the left-hand turnout on the outer loop. This seems like a simple enough wiring situation and I can handle this part of it.

Here's my conundrum: From an operating stand point, It would be best if the same toggle switch caused the respective turnouts to move at the same time that the switch is thrown. It would just make controlling everything easier. "Flip this switch up to do the cross over, then flip this switches this way, and drive the train across the cross-over."

Will a double pole, double throw switch do the trick? Is it possible to use a regular DPDT switch to activate an 022 turnout? If it is, how do I wire the second side of the DPDT?

Thanks

Tony
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    April 2003
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Cross-Over Wiring Conundrum
Posted by Anonymous on Tuesday, July 22, 2003 9:31 PM
OK, I need some help.

I've built a 44" x 72" (3' 8" x 72") layout that sits on top of my dining room table. It consists of two concentric ovals of track. On one side, there are 4 022 switches set up as two crossovers: one crosses over from the outside loop to the inner loop and the other one goes from the inner to the outer. The layout is built in two halves.

When I wired this up, I split the loops up 4 blocks. Each loop on a half is one block. The way it's constructed, each switch is in a separate block.

Today, I attempted to perform, for the first time, a cross-over with two locomotives on the layout simultaneously. This didn't work the way I envisioned it.

In order for the cross-over to work, I need to power a total of three blocks from the cab that controls the train I want to move. The problem is that the other train has to be occupying one of these blocks, which means that a collision is all but certain.

Let's consider the cross-over from the outer to the inner loop. This is composed of two right-hand turnouts. There's really only two ways the switches can be thrown: either both are straight through, or both are thrown to the alternate path.

Thinking about the problem, I realized that I need to electrically isolate the turnout on the inner loop from the rest of its block. What I'm seeing in my head is a simple toggle switch (2 positions only) which, when thrown in one position, makes the turnout act the way it does now, and, when thrown in the other position, makes it act like a part of the outer loop block (the one that the train is leaving). This way, I have to toggle this switch & set outer loop block on one side & the innner loop block on the other to the same cab.

I then need to do something similar on the other side, only on this side, I'm controlling the left-hand turnout on the outer loop. This seems like a simple enough wiring situation and I can handle this part of it.

Here's my conundrum: From an operating stand point, It would be best if the same toggle switch caused the respective turnouts to move at the same time that the switch is thrown. It would just make controlling everything easier. "Flip this switch up to do the cross over, then flip this switches this way, and drive the train across the cross-over."

Will a double pole, double throw switch do the trick? Is it possible to use a regular DPDT switch to activate an 022 turnout? If it is, how do I wire the second side of the DPDT?

Thanks

Tony
  • Member since
    April 2003
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Posted by Anonymous on Wednesday, July 23, 2003 8:43 PM
OK. I've thought about this problem & I've figured out that I don't have to rewire the blocks. I was trying to get the train on the outside loop onto the inside loop first; if I move the train on the inner loop to the outside loop first, then the wiring doesn't have to change.

Question: Is it possible to get one switch to throw two 022 switches at the same time? It seems like a DPDT ought to do it. Can anyone confirm?

Tony
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    April 2003
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Posted by Anonymous on Wednesday, July 23, 2003 8:43 PM
OK. I've thought about this problem & I've figured out that I don't have to rewire the blocks. I was trying to get the train on the outside loop onto the inside loop first; if I move the train on the inner loop to the outside loop first, then the wiring doesn't have to change.

Question: Is it possible to get one switch to throw two 022 switches at the same time? It seems like a DPDT ought to do it. Can anyone confirm?

Tony
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  • From: Austin, TX
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Posted by lionelsoni on Wednesday, July 23, 2003 10:17 PM
Actually, there is no reason why you cannot control both track switches from a single SPDT switch or the Lionel controller. However, both switches should be powered by the same voltage. There is a socket on the side of the switch motor that accepts a special "fixed voltage plug" (Lionel part 711-151). When the plug is inserted, the switch motor is disconnected from the center rail of the track. You connect the plug to another (usually constant) voltage, relative to the running rails and, in this case of course, use the same voltage for both switches of the pair.
Then connect the outer pair of terminals from both switches to a single (022C-1) controller. Only one switch needs its ground terminal connected to the controller, but there is no harm in connecting both of them. Or you can pick up the ground (the running rails) from a lockon or from the transformer directly if that is more convenient.
If you want to use a non-momentary SPDT switch instead of the momentary switch of the controller, you can; but don't try this with other switches, like the O27 ones, which do not disconnect the motor coil after the switch is thrown--the coils will burn up.
If you do not have the special "fixed voltage plug", you can probably figure out how it works by taking the cover off the motor assembly and then just insulating the little contact finger and connecting the fixed voltage directly to the terminal.
Note that the two track switches do not have to be coordinated, both straight or both diverging. One can be straight, the other diverging. this can allow you to put a compact double crossover in a corner: The inside curve is formed by the diverging branches of two switches. The straight branches of the same switches join the diverging branches of the other two switches, whose straight branches are in the outside main line. The outside curve is made of ordinary track.

Bob Nelson

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  • From: Austin, TX
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Posted by lionelsoni on Wednesday, July 23, 2003 10:17 PM
Actually, there is no reason why you cannot control both track switches from a single SPDT switch or the Lionel controller. However, both switches should be powered by the same voltage. There is a socket on the side of the switch motor that accepts a special "fixed voltage plug" (Lionel part 711-151). When the plug is inserted, the switch motor is disconnected from the center rail of the track. You connect the plug to another (usually constant) voltage, relative to the running rails and, in this case of course, use the same voltage for both switches of the pair.
Then connect the outer pair of terminals from both switches to a single (022C-1) controller. Only one switch needs its ground terminal connected to the controller, but there is no harm in connecting both of them. Or you can pick up the ground (the running rails) from a lockon or from the transformer directly if that is more convenient.
If you want to use a non-momentary SPDT switch instead of the momentary switch of the controller, you can; but don't try this with other switches, like the O27 ones, which do not disconnect the motor coil after the switch is thrown--the coils will burn up.
If you do not have the special "fixed voltage plug", you can probably figure out how it works by taking the cover off the motor assembly and then just insulating the little contact finger and connecting the fixed voltage directly to the terminal.
Note that the two track switches do not have to be coordinated, both straight or both diverging. One can be straight, the other diverging. this can allow you to put a compact double crossover in a corner: The inside curve is formed by the diverging branches of two switches. The straight branches of the same switches join the diverging branches of the other two switches, whose straight branches are in the outside main line. The outside curve is made of ordinary track.

Bob Nelson

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  • From: Guelph, Ont.
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Posted by BR60103 on Wednesday, July 23, 2003 10:59 PM
Consider this block system: put the two switches that are closet together (the switch machines should be closest) into the same block. Adjust where the other blocks come on that loop.
You may find that 3 blocks on each loop gives you the flexibility you need.

--David

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  • From: Guelph, Ont.
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Posted by BR60103 on Wednesday, July 23, 2003 10:59 PM
Consider this block system: put the two switches that are closet together (the switch machines should be closest) into the same block. Adjust where the other blocks come on that loop.
You may find that 3 blocks on each loop gives you the flexibility you need.

--David

  • Member since
    April 2003
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Posted by Anonymous on Thursday, July 24, 2003 8:55 AM
Lionelsoni:

Thanks for the information!

The switches were purchased new several weeks ago & came with the "fixed voltage plug." What voltage do I need to use, or is that listed in the instructions for the switch? I'm at work right now, so I can't look it up. Obviously, since I'm at work, the answer can wait till later.

The more I think about it, the more I'm tempted to try putting each trunout into a separate block and using a DPDT to control both which cab the turnout is connected to AND throwing the turnouts. Doing this would allow me to swap loops starting with either the inner or outer loops.

Tony
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    April 2003
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Posted by Anonymous on Thursday, July 24, 2003 8:55 AM
Lionelsoni:

Thanks for the information!

The switches were purchased new several weeks ago & came with the "fixed voltage plug." What voltage do I need to use, or is that listed in the instructions for the switch? I'm at work right now, so I can't look it up. Obviously, since I'm at work, the answer can wait till later.

The more I think about it, the more I'm tempted to try putting each trunout into a separate block and using a DPDT to control both which cab the turnout is connected to AND throwing the turnouts. Doing this would allow me to swap loops starting with either the inner or outer loops.

Tony
  • Member since
    December 2001
  • From: Austin, TX
  • 10,091 posts
Posted by lionelsoni on Thursday, July 24, 2003 11:03 AM
The voltage would be a normal track voltage, about 16 volts. Most transformers have a constant-voltage output for accessories and purposes like this. The usual reason for using this connection is to be able to throw the switch even though the train is stopped. But you could put the fixed-voltage plug into one switch of a crossover pair and then wire that to the center rail connection of the other switch. That way both switche motors would be powered by the track voltage of the second switch. I would go for the fixed voltage, however, and get all the benefit of it.
If you can tell your transformer model, I might be able to figure out the terminal connections for the fixed voltage for you; or, if I don't have the information, someone else may.

Bob Nelson

  • Member since
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  • From: Austin, TX
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Posted by lionelsoni on Thursday, July 24, 2003 11:03 AM
The voltage would be a normal track voltage, about 16 volts. Most transformers have a constant-voltage output for accessories and purposes like this. The usual reason for using this connection is to be able to throw the switch even though the train is stopped. But you could put the fixed-voltage plug into one switch of a crossover pair and then wire that to the center rail connection of the other switch. That way both switche motors would be powered by the track voltage of the second switch. I would go for the fixed voltage, however, and get all the benefit of it.
If you can tell your transformer model, I might be able to figure out the terminal connections for the fixed voltage for you; or, if I don't have the information, someone else may.

Bob Nelson

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    April 2003
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Posted by Anonymous on Thursday, July 24, 2003 1:01 PM
Lionelsoni:

Thanks again!

Everything on my transformer (a no. 1044) is clearly marked. There are two different terminal posts that give two different fixed voltages. I don't remember which is which right now, but I'm sure I can figure it out when I have the transformer right in front of me.

Tony
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Posted by Anonymous on Thursday, July 24, 2003 1:01 PM
Lionelsoni:

Thanks again!

Everything on my transformer (a no. 1044) is clearly marked. There are two different terminal posts that give two different fixed voltages. I don't remember which is which right now, but I'm sure I can figure it out when I have the transformer right in front of me.

Tony
  • Member since
    December 2001
  • From: Austin, TX
  • 10,091 posts
Posted by lionelsoni on Thursday, July 24, 2003 9:21 PM
Just to be sure, and in case anyone else is interested, let me run through the terminals.
Terminal A would normally connect to the running rails and would be considered "ground", although the transformer does not actually ground it.
Terminal B puts out a constant 5 volts relative to terminal A, not usually used for anything.
Terminal C puts out a constant 16 volts relative to terminal A (and 11 volts relative to terminal B). This is the "fixed voltage" that you would connect to the plugs on the 022 switches.
Terminal U puts out a voltage that varies with the position of the control handle between 5 and 16 volts, except that it is disconnected when the handle is in the extreme counter-clockwise position. It should connect to the center rail(s), through whatever block switching you decide to use.
It is possible to use terminal B as the "ground" instead of A; but then your maximum track voltage is only 11 volts, and so is the "fixed voltage". This is however, plenty for throwing the switches, so use terminal B if you don't need the full 16 volts. Most locomotives will not start below 5 volts, which is why the usual arrangement (terminal A grounded) is satisfactory. But a particularly free-running locomotive that takes off abruptly when the 5 volts hits it might give you a reason for grounding terminal B instead.
I keep forgetting to put my name on these:
Bob Nelson

Bob Nelson

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Posted by lionelsoni on Thursday, July 24, 2003 9:21 PM
Just to be sure, and in case anyone else is interested, let me run through the terminals.
Terminal A would normally connect to the running rails and would be considered "ground", although the transformer does not actually ground it.
Terminal B puts out a constant 5 volts relative to terminal A, not usually used for anything.
Terminal C puts out a constant 16 volts relative to terminal A (and 11 volts relative to terminal B). This is the "fixed voltage" that you would connect to the plugs on the 022 switches.
Terminal U puts out a voltage that varies with the position of the control handle between 5 and 16 volts, except that it is disconnected when the handle is in the extreme counter-clockwise position. It should connect to the center rail(s), through whatever block switching you decide to use.
It is possible to use terminal B as the "ground" instead of A; but then your maximum track voltage is only 11 volts, and so is the "fixed voltage". This is however, plenty for throwing the switches, so use terminal B if you don't need the full 16 volts. Most locomotives will not start below 5 volts, which is why the usual arrangement (terminal A grounded) is satisfactory. But a particularly free-running locomotive that takes off abruptly when the 5 volts hits it might give you a reason for grounding terminal B instead.
I keep forgetting to put my name on these:
Bob Nelson

Bob Nelson

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Posted by lionelsoni on Friday, July 25, 2003 9:41 AM
Here is another reason not to use a non-momentary switch to control the 022 track switches: The non-derailing feature will not work. If a train comes into the switch with the switch set against it, the points will either buzz back and forth between the two tracks or stop in the middle.

Bob Nelson

Bob Nelson

  • Member since
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Posted by lionelsoni on Friday, July 25, 2003 9:41 AM
Here is another reason not to use a non-momentary switch to control the 022 track switches: The non-derailing feature will not work. If a train comes into the switch with the switch set against it, the points will either buzz back and forth between the two tracks or stop in the middle.

Bob Nelson

Bob Nelson

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Posted by Anonymous on Friday, July 25, 2003 11:43 AM
That might not be a problem for me. The only way that a train could enter the diverging section is if I've already thrown the two turnouts to the diverging route, which I intend to do with only one toggle switch.

Does anybody make a DPDT that's half momentary contact and half toggle switch? (I doubt it!)

Still, I'm gonna think about this before I do anything. I just might leave the wiring alone and use two of the lionel momentary contact switches to throw the turnouts.

Tony
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Posted by Anonymous on Friday, July 25, 2003 11:43 AM
That might not be a problem for me. The only way that a train could enter the diverging section is if I've already thrown the two turnouts to the diverging route, which I intend to do with only one toggle switch.

Does anybody make a DPDT that's half momentary contact and half toggle switch? (I doubt it!)

Still, I'm gonna think about this before I do anything. I just might leave the wiring alone and use two of the lionel momentary contact switches to throw the turnouts.

Tony
  • Member since
    December 2001
  • From: Austin, TX
  • 10,091 posts
Posted by lionelsoni on Friday, July 25, 2003 12:29 PM
It would be a problem if the train could enter the switch on the straight route while it is thrown to the diverging route.
Yes, such switches are made. One is the Alcoswitch A207SYZQ, which can be found on the Mouser web site for about $10.

Bob Nelson

Bob Nelson

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  • From: Austin, TX
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Posted by lionelsoni on Friday, July 25, 2003 12:29 PM
It would be a problem if the train could enter the switch on the straight route while it is thrown to the diverging route.
Yes, such switches are made. One is the Alcoswitch A207SYZQ, which can be found on the Mouser web site for about $10.

Bob Nelson

Bob Nelson

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Posted by Anonymous on Friday, July 25, 2003 8:44 PM
Hey, thanks a lot Bob! I appreciate the part number & all the help!

Tony
  • Member since
    April 2003
  • 305,206 posts
Posted by Anonymous on Friday, July 25, 2003 8:44 PM
Hey, thanks a lot Bob! I appreciate the part number & all the help!

Tony

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