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DC wiring question on a new layout

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Posted by gregc on Sunday, June 13, 2021 12:07 PM

sorry.   it seems i'm just adding to the confusion

CSX Robert
gregc
the arrow is confusing in the controller schematic (upper right). there is a permanent connection between the screw terminals.   I verified this with a multimeter with the reversing switches centered.    they've confusingly drawn the connection going thru the switch.

you're right, i'm wrong, there is no direct connection between the cab reversing switch and the output terminals (right side) 

the cab A screw terminals on the right side go thru the cab reversing switch, allowing the polarity on the right side terminals to be reversed.

CSX Robert
  The other two positions connect one leg of the corresponding cab to the outer output terminal (top terminal for cab A and bottom terminal for cab B) and the other leg to the common terminal.

i believe you're saying that the cab-A reversing switch also connects the C (common) terminal at the top of the controller to bottom cab A screw terminal on the right side.   the top cab A screw terminal on the right side is the non-common rail connection

CSX Robert
 
gregc
and yes, if the plastic cab reversing switch is in the middle, there is no connection between common rail terminal, C, power pack.   The switch should not set in that position

The switch is supposed to be set in that position on all but the right-most controller when there are two or more.

ATLANTIC CENTRAL
The cab reverse switches on the ADDITIONAL Controllers must remain in the center pass thru position on those controllers.

the center position (there are no detents) disconnects the ride side terminals from the input side on the left .   the left position is a pass thru, the right position reverses (verified with multimeter)

CSX Robert
  
gregc
the bottom diagram also indicates that the common rail connection C is from the right-most 220 controller, meaning that it is the result of passing thru several cab reversing switches on one or more 220 controllers as well as the throttle itself.

The common does pass through all of the controllers (on the cab inputs/outputs), but you cannot pick it up until the last one because you cannot determine which leg of each cab is common until after the reversing switches in the last controller.

that's what the diagram shows

ATLANTIC CENTRAL
Only the right most Controller is used as the MAIN LINE reversing switch.

i agree because any other would also reverse the polarity going to the X-Y reversing switch

Lastspikemike
Did we also verify that, assuming the two power packs depicted by Atlas are identical, that Atlas shows the positive and negative outputs connected incorrectly to the 220? If yiu connect as shown you will get a dead short. 

why?

for separate cabs there are no common connections between the cabs unless one output is connected to AC ground

Lastspikemike
DC powerpacks have positive and negative output terminals or they wouldn't need a reversing switch to operate trains.

of course the output i DC.  the reversing switch is between the output terminals and the circuit inside controlling the output voltage.   that is why polarity is not marked on the output terminals.

greg - Philadelphia & Reading / Reading

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Posted by Overmod on Sunday, June 13, 2021 11:04 AM

Lastspikemike
I wired ours up wrong and they didn't work. Wiring them correctly, not as shown by Atlas, worked. But then I was connecting a MRC 780 twin throttle powerpack to the 220's.

Remember what Sheldon said a little earlier

IMPORTANT - the Atlas system, and common rail in general, will not work with dual power packs fed from a single internal transformer. You will get a short when you hook up the common wire and reverse the direction of one throttle in relationship to the other.

If I recall correctly the 780 is one of those with a common primary and the equivalent of two taps to supply the two 'cabs'.

I think it's time for 'chapter 2' of the explanational posts, about how the various DC devices actually work (and, in some cases, fail to work as expected).

 

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Posted by Lastspikemike on Sunday, June 13, 2021 10:22 AM

CSX Robert

 

 
Lastspikemike
Did we also verify that, assuming the two power packs depicted by Atlas are identical, that Atlas shows the positive and negative outputs connected incorrectly to the 220? If yiu connect as shown you will get a dead short.

 

No we did not verify that because it is not true.

Ignoring the cab selector and reversing switch for the reversing (X-Y) section, ther Eare five settings for 220.

The first setting has both cab revresing switches set to the middle position.  It connects the cab A and B inputs directly to the right hand side outputs and leaves the C terminal unconnected:

202

Here are the other four combinatons (I've labeled the switch postions up and down to match the schematic even though physically they are left and right) :

 Up-up

Up-down

 Down-up

Down-down

For each cab and each position, one input is connected to the outer (upper cab A, lower cab B) output terminal for that cab, the other input is connected to the common terminal, the inner output terminals are left unconnected, and there are no shorts anywhere.

 

Thanks for doing that. 

The two "up down" coloured schematics seem to show the short circuit I refer to. The opposite polarities of the powerpacks connect at the Common terminal. That looks to me like a dead short. Why is it not?

Also, if you do colour in the reversing section power flow you can't get positive and negative power to that circuit unless you reverse one pair of the input  connections. The Cab selector switch would connect negative to positive, a dead short.

Does it make a difference if you gang two or more 220 together and show the polarity of current flow across the 220's with the main reversing switches at center off?

Common terminal power has to connect to the reversing section outputs for each 220 even if the main reversing switches are set to center off the Common rail  current flow comes back to that set of terminals in order to separately control the polarity of the reversing section (Wye or TT).

The first version of the 220 had no flow through for the Common terminal so this situation could not arise. 

Alyth Yard

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Posted by Lastspikemike on Sunday, June 13, 2021 10:14 AM

Well, I'll check it again someday. At the moment both my view of the schematic, my testing with my multi meter and my experience wiring ganged 220 say otherwise. I wired ours up wrong and they didn't work. Wiring them correctly, not as shown by Atlas, worked. But then I was connecting a MRC 780 twin throttle powerpack to the 220's.

DC powerpacks have positive and negative output terminals or they wouldn't need a reversing switch to operate trains. Multimeters display reversed polarity, digital with a minus sign and analogue by driving the needle backwards. 

I still say that because the C terminal has to feed the reversing section terminals and that only one polarity reaches the block selector switches that it matters which way around the four input terminals on the 220 are connected to the two powerpacks. But I'm no electrical genius so I may be mistaken. 

Heck I still think all the Cabs must have the same polarity terminal connected to the common rail.....

Alyth Yard

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Posted by SeeYou190 on Sunday, June 13, 2021 10:03 AM

I do not understand labelling power pack track outputs.

The track output is polarity reversable by the direction switch on the power pack. It does not have a positive or a negative.

Confused

-Kevin

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by CSX Robert on Sunday, June 13, 2021 9:51 AM

Lastspikemike
Did we also verify that, assuming the two power packs depicted by Atlas are identical, that Atlas shows the positive and negative outputs connected incorrectly to the 220? If yiu connect as shown you will get a dead short.

No we did not verify that because it is not true.

Ignoring the cab selector and reversing switch for the reversing (X-Y) section, ther Eare five settings for 220.

The first setting has both cab revresing switches set to the middle position.  It connects the cab A and B inputs directly to the right hand side outputs and leaves the C terminal unconnected (Edit: I meant to point out in that anything marked in yellow in these diagrams is unconnected):

202

Here are the other four combinatons (I've labeled the switch postions up and down to match the schematic even though physically they are left and right) :

 Up-up

Up-down

 Down-up

Down-down

For each cab and each position, one input is connected to the outer (upper cab A, lower cab B) output terminal for that cab, the other input is connected to the common terminal, the inner output terminals are left unconnected, and there are no shorts anywhere.

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Posted by ATLANTIC CENTRAL on Sunday, June 13, 2021 9:32 AM

Robert gets it.

The Atlas Controller serves three functions. It provides a MAIN LINE reversing switch for each throttle AFTER a power tap for a reversing loop. It provides a cab selection switch for the reversing loop, and it provides the necessary separate reversing switch for that loop.

IF you have more than one reverse loop, Controllers are added to the left for each additional loop.

The cab reverse switches on the ADDITIONAL Controllers must remain in the center pass thru position on those controllers. Only the right most Controller is used as the MAIN LINE reversing switch.

For what it is, the Atlas system works fine, you just need to set it up correctly and know what each switch does and know which ones to leave alone.

And maybe, you need to accept the established conventions of MAINLINE and REVERSE LOOP?

IMPORTANT - the Atlas system, and common rail in general, will not work with dual power packs fed from a single internal transformer. You will get a short when you hook up the common wire and reverse the direction of one throttle in relationship to the other.

Over the years many better dual packs actually had separate internal transfomers because common rail was popular back in the day.

You must have a separate transformer (derived source) for each throttle to use common rail for multi train cab control.

For those who don't undertand this, I will explain transformer theory and why you don't get a short with two separate power packs some other day.

Meanwhile, I am working on a best design for the OP's track plan.....

Sheldon 

 

    

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Posted by SeeYou190 on Sunday, June 13, 2021 8:58 AM

Lastspikemike
And what would that be?

I think you are purposely "playing dumb" to start some discord. There is no way you do not understand common rail.

Anyway... common rail has one continously electrically connected rail that shares one terminal in common with each power pack output. That "rail" is "common" to all power sources.

There, now you don't need to pretend that you don't understand.

Zzz

-Kevin

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by Lastspikemike on Sunday, June 13, 2021 8:50 AM

SeeYou190

 

 
Lastspikemike
So, clearly, there is not a commonly accepted definition of common rail.

 

I am pretty sure there has been a universally understood definition of common rail DC wiring for 60+ years.

Confused

-Kevin

 

And what would that be?

I suggest evidently not.

I propose that Common Rail is more correctly described as "Control Rail" since that is its distinguishing feature. The idea is you can select and electrically control separate blocks with isolating gaps in only the one rail.  You do not need two powerpacks.

The misconception that you need more than one Cab to have a Common Rail layout probably arises from the advantages Common Rail affords if you add Cabs to a DC layout. 

For DCC you can use Common Rail with one powerpack and single control rail quite conveniently. What you don't want to do is try running Common Rail with multiple booster units. This is very important to get straight in your mind. 

Common Rail is ideal for DCC, in its simplest form, with one booster usually integral with the command station. What could be easier to wire? You don't even need any blocks. Hence my remark about both rails being common rails in the simpler DCC layouts. 

Somewhat ironically, if you wish to run DC locomotives on occasion using say a Tech 6 then you'll want to put at least some control rail sections into your layout (to park the DCC locomotives) unless you want to have to take all your DCC locomotives off the layout just to run the one DC locomotive. Now that's a nuisance.

Some new trainsets now are coming out with the advantages of simple two rail wiring and the benefits of DCC, it's like magic.

Alyth Yard

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Posted by CSX Robert on Sunday, June 13, 2021 8:42 AM

gregc
the arrow is confusing in the controller schematic (upper right). there is a permanent connection between the screw terminals.   I verified this with a multimeter with the reversing switches centered.    they've confusingly drawn the connection going thru the switch.

The arrow is just showing one position of the reversing switch.  There is not a direct connection between the cab input and output terminals, the cab reversing switches are three position switches and the center position does connect the inputs straight to the outputs.  The other two positions connect one leg of the corresponding cab to the outer output terminal (top terminal for cab A and bottom terminal for cab B) and the other leg to the common terminal.

gregc
and yes, if the plastic cab reversing switch is in the middle, there is no connection between common rail terminal, C, power pack.   The switch should not set in that position

The switch is supposed to be set in that position on all but the right-most controller when there are two or more.

gregc
the bottom diagram also indicates that the common rail connection C is from the right-most 220 controller, meaning that it is the result of passing thru several cab reversing switches on one or more 220 controllers as well as the throttle itself.

The common does pass through all of the controllers (on the cab inputs/outputs), but you cannot pick it up until the last one because you cannot determine which leg of each cab is common until after the reversing switches in the last controller.

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Posted by Lastspikemike on Sunday, June 13, 2021 8:41 AM

Did we also verify that, assuming the two power packs depicted by Atlas are identical, that Atlas shows the positive and negative outputs connected incorrectly to the 220? If yiu connect as shown you will get a dead short. 

The last 220 in a gang is connected to the 215 Selector through the outer output terminals. The two inner output terminals are not connected to a 215 at all. In fact if you connect a newer 215 to an older 220 with terminal bars you have to cut off the two inner output terminals in order to get the 215 close enough to connect.  The original 220 did not have pass through Common output terminals.

The 220 reversing switches both pass through the Common connection and are center off, if you do not have the reversing switches on all but the last 220 in the center off position you will have open circuit. 

The actual reason to use a 220 is for its integral reversing switch.

Alyth Yard

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Posted by SeeYou190 on Sunday, June 13, 2021 8:36 AM

Lastspikemike
So, clearly, there is not a commonly accepted definition of common rail.

I am pretty sure there has been a universally understood definition of common rail DC wiring for 60+ years.

Confused

-Kevin

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by gregc on Sunday, June 13, 2021 5:10 AM

CSX Robert
 
Lastspikemike

Looking at the 220 schematic again I see how Atlas indicates the center off flow through for the Common terminal. The lower Cab B reversing switch is shown in the center off position and the direct connection is shown. Cab A reversing switch is shown in the live position activating the Block output connections. You would never actually operate the 220 in this configuration.

greg - Philadelphia & Reading / Reading

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Posted by CSX Robert on Saturday, June 12, 2021 9:09 PM

Lastspikemike

Looking at the 220 schematic again I see how Atlas indicates the center off flow through for the Common terminal. The lower Cab B reversing switch is shown in the center off position and the direct connection is shown. Cab A reversing switch is shown in the live position activating the Block output connections. You would never actually operate the 220 in this configuration.

Thge schematic you're looking at must not be the same as the one Greg posted then(which is also available on the Atlas website).  That schematic shows both cabs A and B in the center position, with the cab inputs connected directly to the right side outputs and no connection to common (because again, with mutiple 220's you can not pick up common until after the cab direction switches in the last 220).

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Posted by Lastspikemike on Saturday, June 12, 2021 8:10 PM

Looking at the 220 schematic again I see how Atlas indicates the center off flow through for the Common terminal. The lower Cab B reversing switch is shown in the center off position and the direct connection is shown. Cab A reversing switch is shown in the live position activating the Block output connections. You would never actually operate the 220 in this configuration.

The remainder of my remarks are correct. 

Alyth Yard

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Posted by ATLANTIC CENTRAL on Saturday, June 12, 2021 7:24 PM

I was able to see and download the track plan, I will get back to you as soon as I can look it over.

To the right of your screen, should be your account profile info. There should be a button that says "messages" - that is the private message portal.

If it's not there or does not work, don't be concerned, not all the features work correctly for everyone, the software is old.....

Be back to you soon,

Sheldon

    

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Posted by CSX Robert on Saturday, June 12, 2021 7:12 PM

There actually is a minor error in the schematic, but it's pretty obvious how it's supposed to be.  In the cab B reversing switch, one of the connections to the C circuit is missing.

Lastspikemike
In particular, the circuit to  the "common rail" output from the same polarity input is not shown

The circuit to the common rail output from the "same polarity input" is not shown because the common rail output is not necessarily wired to the same polarity and is not wired directly to the cab inputs.  The common goes after the cab direction switch because which polarity of each input it goes to depends on the direction switch for that input.

Lastspikemike
Describe the line on the schematic that shows how the common rail power flows from either Cab A or B input terminal through the 220 to power the input terminal on the ganged 220.

When the cab direction switches are in the center position, cab A and B inputs are connected directly to cab A and B outputs, just as the schematic shows.  There is no connection to common because you cannot pick it up until after the direction switches in the last 220, before that you don't know which side of each cab circuit is common.

Lastspikemike
The inner of the two input terminals flow though the C common rail connection according to the schematics

No they don't.  The common rail connection goes to the two cab direction switches and whether or not it is connected to an input and if so which one is determnined by the direction switches.

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Posted by Ablebakercharlie on Saturday, June 12, 2021 5:24 PM

Here is a pic of the layout - that is if I did the correct things.....

DC Train Layout

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Posted by Ablebakercharlie on Saturday, June 12, 2021 4:57 PM

ATLANTIC CENTRAL

 

 
Ablebakercharlie

 

 
jjdamnit
  • Another option would be to use terminal strips (A.K.A. terminal blocks or barrier strips). These come in "sizes" from 2- to 10-terminals.
  • To energize the entire strip you can fabricate jumpers from spade connectors and short pieces of wire or buy jumpers made of solid metal to connect the terminals.

  • From there it's a matter of running wires from the lugs (screw terminals) on the terminal strip to the track section. 

Before converting my 4' X 8' pike to DCC I had 16 control blocks (4 atlas controllers) with only a single "negative" common.

Because of the size of my pike I found 20 AWG wire sufficient for the power feeds for both the common and blocks.

For the turnouts I used a separate power source connected to two Capacitive Discharge Units through Atlas switch control boxes (#56). But that's another post.

Keep the questions coming, update us on your progress, and...

Hope this helps.

 

 

 

 

Hello All,

Thanks very much everyone for your input re my wiring question!  Much appreciated. 

The first response by jjdamnit addressed my main issue re the Atlas 215 selectors.  I want to take the approach of wiring each block as a stand alone to make trouble shooting easier.   Because something always goes wrong with wiring, right? Or is it just me?  :)   I couldn't visualize using the terminal strips for the second leg (that's the correct term, right?) for all the blocks but now it seems simple.

 I got the Atlas selectors as I thought they were a reliable means for blocking but it sounds like there are some better alternatives.  Since I bought them I am going to go with them for now but will start researching alternatives.  

Sheldon, if you read this, I would be interested in your approach to DC wiring.   I would love to do a wireless set up but internet searches have not come up with success.

Once again,  thanks everyone.  I enjoy reading the spirited debate on layout preferences and am continually amazed by the wealth of information that can be obtained from the membership by simply just posting a question!

 

charles

 

 

 

 

Charles, I would be happy to help. My first question is do you have a track plan you can post or email?

Then I would like to know a little about what you would like to be able to do, how you would like to operate your layout.

If you know how the private message feature works on this forum, and yours is working, feel free to send me a private measage.

Sheldon

 

Sheldon,

Thank you very much for responding.  I have enjoyed reading your posts since I have been "lurking" these past couple months and have wanted to get your input re a DC layout setup since that is your set-up choice vs DCC.  

Now I must sheepishly admit I can't figure out how to send a PM - I looked in the profile / settings section and couldn't figure it out.  Can you or someone else offer assistance?  I would be happy to post /send the layoutplan and track pics for critique.

With much appreciation,

 

charles

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Posted by gregc on Saturday, June 12, 2021 4:33 PM

Lastspikemike
To understand my remark you need to understand that the two reversing switches in the 220 just always be set to center off when ganging the 220's. Terminal C is then not connected in any 220 in the gang except the last one.

i think what you're trying to say is that if the cab reversing switch is set to the center position, the C terminal is unconnected.

i don't believe the cab reversing section is intended to be set to the center.

greg - Philadelphia & Reading / Reading

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Posted by ATLANTIC CENTRAL on Saturday, June 12, 2021 4:32 PM

Ablebakercharlie

 

 
jjdamnit
  • Another option would be to use terminal strips (A.K.A. terminal blocks or barrier strips). These come in "sizes" from 2- to 10-terminals.
  • To energize the entire strip you can fabricate jumpers from spade connectors and short pieces of wire or buy jumpers made of solid metal to connect the terminals.

  • From there it's a matter of running wires from the lugs (screw terminals) on the terminal strip to the track section. 

Before converting my 4' X 8' pike to DCC I had 16 control blocks (4 atlas controllers) with only a single "negative" common.

Because of the size of my pike I found 20 AWG wire sufficient for the power feeds for both the common and blocks.

For the turnouts I used a separate power source connected to two Capacitive Discharge Units through Atlas switch control boxes (#56). But that's another post.

Keep the questions coming, update us on your progress, and...

Hope this helps.

 

 

 

 

Hello All,

Thanks very much everyone for your input re my wiring question!  Much appreciated. 

The first response by jjdamnit addressed my main issue re the Atlas 215 selectors.  I want to take the approach of wiring each block as a stand alone to make trouble shooting easier.   Because something always goes wrong with wiring, right? Or is it just me?  :)   I couldn't visualize using the terminal strips for the second leg (that's the correct term, right?) for all the blocks but now it seems simple.

 I got the Atlas selectors as I thought they were a reliable means for blocking but it sounds like there are some better alternatives.  Since I bought them I am going to go with them for now but will start researching alternatives.  

Sheldon, if you read this, I would be interested in your approach to DC wiring.   I would love to do a wireless set up but internet searches have not come up with success.

Once again,  thanks everyone.  I enjoy reading the spirited debate on layout preferences and am continually amazed by the wealth of information that can be obtained from the membership by simply just posting a question!

 

charles

 

 

Charles, I would be happy to help. My first question is do you have a track plan you can post or email?

Then I would like to know a little about what you would like to be able to do, how you would like to operate your layout.

If you know how the private message feature works on this forum, and yours is working, feel free to send me a private measage.

Sheldon

    

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Posted by SeeYou190 on Saturday, June 12, 2021 2:10 PM

RR_Mel
Good choice, Sheldon is the goto guy for DC wiring.

Yes +1.

-Kevin

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by RR_Mel on Saturday, June 12, 2021 1:55 PM

Charles

Good choice, Sheldon is the goto guy for DC wiring.


Mel
 
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Posted by Ablebakercharlie on Saturday, June 12, 2021 1:44 PM

jjdamnit
  • Another option would be to use terminal strips (A.K.A. terminal blocks or barrier strips). These come in "sizes" from 2- to 10-terminals.
  • To energize the entire strip you can fabricate jumpers from spade connectors and short pieces of wire or buy jumpers made of solid metal to connect the terminals.

  • From there it's a matter of running wires from the lugs (screw terminals) on the terminal strip to the track section. 

Before converting my 4' X 8' pike to DCC I had 16 control blocks (4 atlas controllers) with only a single "negative" common.

Because of the size of my pike I found 20 AWG wire sufficient for the power feeds for both the common and blocks.

For the turnouts I used a separate power source connected to two Capacitive Discharge Units through Atlas switch control boxes (#56). But that's another post.

Keep the questions coming, update us on your progress, and...

Hope this helps.

 

 

Hello All,

Thanks very much everyone for your input re my wiring question!  Much appreciated. 

The first response by jjdamnit addressed my main issue re the Atlas 215 selectors.  I want to take the approach of wiring each block as a stand alone to make trouble shooting easier.   Because something always goes wrong with wiring, right? Or is it just me?  :)   I couldn't visualize using the terminal strips for the second leg (that's the correct term, right?) for all the blocks but now it seems simple.

 I got the Atlas selectors as I thought they were a reliable means for blocking but it sounds like there are some better alternatives.  Since I bought them I am going to go with them for now but will start researching alternatives.  

Sheldon, if you read this, I would be interested in your approach to DC wiring.   I would love to do a wireless set up but internet searches have not come up with success.

Once again,  thanks everyone.  I enjoy reading the spirited debate on layout preferences and am continually amazed by the wealth of information that can be obtained from the membership by simply just posting a question!

 

charles

 

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Posted by CSX Robert on Saturday, June 12, 2021 10:05 AM

Lastspikemike
So which way is "clockwise" on a single track connecting two continuous running loops? And if the polarity of the exit from one loop is opposite to the polarity at the entry to the other loop which is the "correct" direction?

Did you actually read his post or just skim it?  He talked about clockwise and counter clockwise specifically in reference to loops, as well as pointing out that "every layout is a little different and may require different solutions."

 

Lastspikemike
If you use Atlas 220 controllers there is no "main line" to have default polarity

The "mainline" when using Atlas 220 controllers is whatever is connected to the right-hand side outputs of the controller.

 

Lastspikemike
If you use fully isolated blocks with independent polarity control (DPDT to each block) for each block which block is the main line? 

 

You generally don't have independent direction control for each block (for each block on the mainline the direction is controlled by the cab currently selected, not an independent direction switch for that block), you have direction control for each cab and each reversing section, but again "every layout is a little different and may require different solutions."

 

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Posted by ATLANTIC CENTRAL on Saturday, June 12, 2021 10:02 AM

Two parallel tracks should have the same "east - west" orientation and not require a reversing section.

The real problem here is the rest of the short sighted thinking about cab control and how to connect the track sections to the throttles. But this is all I have time for.

Sheldon 

    

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Posted by Lastspikemike on Saturday, June 12, 2021 9:52 AM

So which way is "clockwise" on a single track connecting two continuous running loops? And if the polarity of the exit from one loop is opposite to the polarity at the entry to the other loop which is the "correct" direction?

If you use Atlas 220 controllers there is no "main line" to have default polarity. If you use fully isolated blocks with independent polarity control (DPDT to each block) for each block which block is the main line? 

I fully recognize the dyed in the wool views of many posters to this forum.   

Not many fresh "faces" though, perhaps there's a cause and effect connection there.

Alyth Yard

Canada

  • Member since
    February 2007
  • From: Christiana, TN
  • 1,808 posts
Posted by CSX Robert on Saturday, June 12, 2021 9:42 AM

Lastspikemike
Incidentally, it is actually confusing to refer to reversing sections and "main lines" as if these are different electrically. It makes more sense to realize that electrically speaking you automatically create two reversing sections as soon as you create one.

While you can change a train's travel direction with the direction switch, it can travel anywhere on the mainlines and will never change the direction it is physically pointing relative to the track.  When the train traverses a reversing section, it can change the direction it is physically pointing, how is labeling that a reversing section confusing?

 

When you add a reversing section, either section of the layout could be considered a reversing section relative to the other (section 'A' reverses trains for section 'B' or section B reverses trains for section 'A'), but most layouts have a section that makes sense to have as the "mainline" with any reversing sections reversing trains relative to that mainline.

  • Member since
    September 2004
  • From: Dearborn Station
  • 21,708 posts
Posted by richhotrain on Saturday, June 12, 2021 9:37 AM

Overmod
 
jjdamnit
Since you are using Atlas controllers I suggest purchasing The Complete Atlas Wiring Book... Unfortunately, it is currently listed as Backorder on the Atlas website. 

At least two copies of the 2017 edition of this #12 are currently up on eBay for close to the listed price.  I'm reasonably sure 'used' copies will show up on Amazon or some of the 'discount' book sites from time to time. 

Why bother if the information and diagrams in the book are incorrect?

Rich

Alton Junction

  • Member since
    February 2010
  • From: Indiana
  • 196 posts
Posted by mikeGTW on Saturday, June 12, 2021 9:33 AM
I just tried calling Atlas and only Mon thru Fri so I will call them and see what they have to say

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