Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

DC block wiring Locked

8199 views
62 replies
1 rating 2 rating 3 rating 4 rating 5 rating
Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Saturday, September 5, 2020 4:05 PM

Wow...another locked thread on a weekend.  Never a dull moment on the forum...

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Saturday, September 5, 2020 4:03 PM

I think I’m over my mad.  I hope the newbie hangs around, this was an unusual experience and I shouldn’t have come unglued like I did.  I apologize for my rant.

Just not used to someone taking a shot at me, that one hit me dead center.

Not offering excuses but the Bako heat doesn’t help, it’s 104° at 27% H outside on the way to 106° and the AC is working overtime.


Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
    September 2004
  • From: Dearborn Station
  • 24,281 posts
Posted by richhotrain on Saturday, September 5, 2020 3:57 PM

Overmod
 
richhotrain
In fairness to Mel, he didn't say that common rail couldn't be used on a layout with reverse loops. 

I don't even think Mel raised the issue of reversing loops not working with common rail in the first place.  

LOL, that is so true. It was poor Marlon (Medina1128) who raised the issue in the first place. Happy Saturday Evening everyone!  

Rich

Alton Junction

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Saturday, September 5, 2020 3:53 PM

richhotrain
In fairness to Mel, he didn't say that common rail couldn't be used on a layout with reverse loops.

I don't even think Mel raised the issue of reversing loops not working with common rail in the first place.  It's that the atmosphere has been so poisoned by the overweening arrogance that he promptly felt any comment to be a jab ... it just so happened that this one wasn't.

I grew up in northern New Jersey, where chopbusting is almost the official state pastime and asserting opinions in discussions strongly regardless of participant reputations is perhaps second only to that of the New York theatre community.  That would not give me the right to question "credentials" of any of the serious modelers here as if their knowledge or wisdom were somehow deficient.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Saturday, September 5, 2020 3:26 PM

I agree common rail will work, I’m not against common rail it’s just not the way I prefer to wire a layout.  My MAD was because he berated me for no reason.  I was trying to help the newbie not confuse him.

 

EDIT:  I ask Tom to block this before it gets really bad.

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
    September 2004
  • From: Dearborn Station
  • 24,281 posts
Posted by richhotrain on Saturday, September 5, 2020 3:25 PM

Dunno, when I first read the comment, I took it the same way that Mel did. Maybe the problem here is that once bitten twice shy. There has been so much sniping going on in the forum lately that it sometimes becomes difficult to separate the sincere from the insincere. In fairness to Mel, he didn't say that common rail couldn't be used on a layout with reverse loops.

Rich

Alton Junction

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Saturday, September 5, 2020 3:17 PM

RR_Mel
I have a EE Degree and 50 years in Two-Way Radio Communications as well as 15 years in Radio & TV broadcast engineering and I have been Modeling HO for 69 years most likely all longer than he has been on this planet and he berated me.

I know.  And I found it frankly appalling that he would do so.  But in the particular post in question he appeared to be very careful to stay objective and fact-based, and non controversial in either tone or expression.

Thanks to him the first time OP on this post probably won't stay.

Yes ... but that in itself is no reason to prejudge his ability to post reasonably when he chooses to do so.

I don't think advocacy of common rail is a 'sin' or that its use is a kind of anathema, even though I dislike it.  As Riddles said to Bulleid "if doctors can differ then so may engineers" and if kept objective, such a difference is not implied insult (or implied iconoclasm!)

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Saturday, September 5, 2020 3:06 PM

Lastspikemike
You can still use common rail for all the track outside the reversing loop.

i agree

you don't need a degree to understand this.  see Linn Westcott's book

greg - Philadelphia & Reading / Reading

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Saturday, September 5, 2020 2:58 PM

I have a EE Degree and 50 years in Two-Way Radio Communications as well as 15 years in Radio & TV broadcast engineering and I have been Modeling HO for 69 years most likely all longer than he has been on this planet and he berated me.

Thanks to him the first time OP on this post probably won't stay.


Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Saturday, September 5, 2020 2:51 PM

RR_Mel
 
Lastspikemike  
Medina1128 

The reason I didn't wire my DC controlled layout for common rail is that I have reverse loops. Once a train enters the reverse loop, you must reverse the polarity of the block leading into the loop. In order to do this, you need to isolate both rails.  

You can still use common rail for all the track outside the reversing loop.

Check the wiring diagram for the Atlas 220 controller (in the Atlas wiring book) and you'll see why. 

He said it was working, why do you keep mucking things up?

In all fairness, he made a legitimate comment here in context, and in fact backed it up with a reference.  What he is saying -- very appropriately in context, imo -- is that simply because you have reversing loops does not mean you can't use common-rail for 'the rest of the layout'.  And I do think that is important to have established at this point in the discussion.  I expect Sheldon might now weigh in not just eith reasons he doesn't use common rail but with specific criticism of the Atlas approach to reversing loops ... if there is some.

Personally I have disliked common-wire since before my teens and have always been a full-isolated-section kinda guy, so I'm not in any way advocating common rail.  But a civil post with legitimate observation backed up by better than arrogance doesn't deserve a dismissive response...

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Saturday, September 5, 2020 2:27 PM

Lastspikemike

 

 
Medina1128

 

 
ATLANTIC CENTRAL
Are you suggesting SPDT switches and common rail? I've been using DC cab control for 53 years and do not recommend common rail wiring. Maybe later when I am not working I can take the time to explain why. Sheldon

 

The reason I didn't wire my DC controlled layout for common rail is that I have reverse loops. Once a train enters the reverse loop, you must reverse the polarity of the block leading into the loop. In order to do this, you need to isolate both rails.

 

 

 

You can still use common rail for all the track outside the reversing loop.

Check the wiring diagram for the Atlas 220 controller (in the Atlas wiring book) and you'll see why.

 

He said it was working, why do you keep mucking everything up?


Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 

  • Member since
    April 2003
  • From: Clinton, MO, US
  • 4,261 posts
Posted by Medina1128 on Saturday, September 5, 2020 12:46 PM

ATLANTIC CENTRAL
Are you suggesting SPDT switches and common rail? I've been using DC cab control for 53 years and do not recommend common rail wiring. Maybe later when I am not working I can take the time to explain why. Sheldon

The reason I didn't wire my DC controlled layout for common rail is that I have reverse loops. Once a train enters the reverse loop, you must reverse the polarity of the block leading into the loop. In order to do this, you need to isolate both rails.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Friday, September 4, 2020 7:10 PM

Common Rail will work but some aspects don’t appeal to me.  I prefer to switch both rails.  I don’t have the Wescott book nor have I read it.

I often have a DC train running my twice around mainline and I can still do switching in my yard, actually just moving a locomotive around in my yard.

I also do other things that don’t conform to common rail, I have siding that I park passenger trains on and I use onboard batteries that trickle while running but when parked on a siding I can switch 12 volts to the siding to charge the batteries.  I also have a yard storage track with the same feature for cabooses.

My layout is dual mode DC or DCC, both rails switched has worked perfect on my layout for 31 years.  No special switches or wiring, everything is normal.  

When I cutover to DCC in 2004 the only wiring change was a relay to switch from DC to DCC powered off the DC power pack to prevent both controllers from being connected to the track.  When I turn on the DC Power Pack (MRC Sound and Power 7000) the relay pulls in and switches the power packs.


Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
    August 2019
  • 47 posts
Posted by hgodling on Friday, September 4, 2020 6:30 PM

dknelson
 

I believe the popular Atlas block control components (and thus the Atlas wiring books) assume common rail.  Westcott's old wiring book shows both.

Dave Nelson

Thank you for sharing your experience Mel. Sounds like it could save me some headaches when I get to that point. 

Does the Westcott book actually refer to this as common rail?

I have a copy of his book from 25+ years ago that I was planning to use, but based on Mel's comments I think it's a safe bet that I want to avoid those issues. I didn't know if names have changed over the years. 

  • Member since
    September 2004
  • From: Dearborn Station
  • 24,281 posts
Posted by richhotrain on Friday, September 4, 2020 5:45 PM

SeeYou190

We are deifnitely dealing with a strange sort of online bullying here. Do not argue with him, it is a waste of effort.

I really need to wonder about the motivations of someone who so desperately craves public victory in an electric train forum.

-Kevin 

Exactly my sentiments, Kevin. All of this braggadocio about college grades, courtroom domination, always being right and sometimes, even "righter", and all on a model railroad forum of all things. Worse yet, it is entirely unprovoked.

I recall my first post-retirement winter in Florida at a golf resort. On my first day playing in a group shotgun format, the group leader introduced himself, welcomed me on board, and took great pains to point out to me that no one in the group cared what I did before I retired whether it be a CEO of a Fortune 500 company, a king or emperor, or whomever. They just care about your handicap, he reminded me.

That same advice holds true on this forum. We just care about your layout, what you model, and maybe a photo here and there of your work. We don't need encyclopedia-like disserations to make a point.

Rich

Alton Junction

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, September 4, 2020 5:25 PM

- -
Experts frequently believe their expertise gives them an advantage in explaining these things. It doesn't. Believe me.

Bang Head  Bang Head  Bang Head  Bang Head  Bang Head  Bang Head  

Unbelievable. Claiming you are better qualified to explain something than the people who are experts.

And I thought it was bad when my intelligence was called into question because I did not have a passport.

Where do we go from here?

RR_Mel
I’m not going to argue you will only nitpick anything I say.

We are deifnitely dealing with a strange sort of online bullying here. Do not argue with him, it is a waste of effort.

I really need to wonder about the motivations of someone who so desperately craves public victory in an electric train forum.

richhotrain
But, Mel, did you get straight A's in mathematics?

I wonder why that was even pointed out?

I have had disagreements with people in here and never once thought that mentioning my marks in the long gone days of academia would bolster the validity my point of view.

What do you know?

-Kevin

Living the dream.

  • Member since
    September 2004
  • From: Dearborn Station
  • 24,281 posts
Posted by richhotrain on Friday, September 4, 2020 4:24 PM

RR_Mel

 

Please give me a bit of credit, I was very successful in electronics for over 50 years.  

But, Mel, did you get straight A's in mathematics???   Laugh

Rich

Alton Junction

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Friday, September 4, 2020 4:11 PM

I’m not going to argue you will only nitpick anything I say.  At least you finally read his post and replied.


Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
    September 2004
  • From: Dearborn Station
  • 24,281 posts
Posted by richhotrain on Friday, September 4, 2020 4:05 PM

Lastspikemike

Experts frequently believe their expertise gives them an advantage in explaining these things. It doesn't. Believe me.  

Never?

Alton Junction

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Friday, September 4, 2020 3:27 PM

 It really goes back to those dual power packs that were popular back in the day. There are two kinds, and for common rail you need to be careful of which type you use. The more common adn cheaper ones ahve a single transformer and rectifier, and then 2 rheostats and direction switches. The more expensive ones are actually two COMPLETE packs in a case, they just have the transformer primaries connected to a single line cord.

 Transformers provide isolation. But if the two outputs come off the same transformer secondary, they are not isolated from each other. This is where the problem comes in. Common rail cannot work if there is only a single shared transformer.

                                           --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    February 2010
  • From: Indiana
  • 225 posts
Posted by mikeGTW on Friday, September 4, 2020 12:27 PM

Mel   you are correct  the only thing different I would say is seperate transformers  cause some store bought ones used the same one for two controls  

And like you been at this for prob 50yrs    30+ signal dept on the real thing   

I was repairing and troubleshooting  motion sensors and predicters for the real ones when I retired  so electronics is not a problem for me 

You think some of our model stuf can run you in circles   try the real ones

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Friday, September 4, 2020 12:03 PM

mikeGTW

Mel quick question  so from what you are saying I can not run an engine anywhere in seperate blocks in opposite directions using common rail?

I use common rail (kind of)  and can run in opposite dir on my mains at the same time   So this should not work?    I have 5 throttles 3 hard wired and two on plugs  Not sure what I'm doing different but it works just fine

 

 

 

Not using the same DC power pack.  You can reverse the polarity if both rails are switchable but you have to be carful not to go into a block with the opposite polarity, a short will occur as the wheels close the gaps.

Early on in my teens I accidently melted the springs in my 0-6-0 tender trucks.  Back then I was using an AC transformer for my power and a selenium rectifier with a rheostat and the fuse wasn’t fast enough.

As Kevin said you can use two isolated power packs with common rail but should you cross into a block powered with the other power pack disaster.  The two voltages will add together and ZAP.


Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

 

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, September 4, 2020 11:53 AM

mikeGTW
Quick question  so from what you are saying I can not run an engine anywhere in seperate blocks in opposite directions using common rail?

You can wire a common rail set up, hook up two Isolated power packs, and run at opposite directions under the control of the two different packs in DC using cab selector switches on the blocks.

There are situations where problems might arise, like long lighted equipment, locomotive consists wired in parallel to one another, some "dual packs" that are not isolated, etc.

Under normal operating you should never have a problem, and common rail works completely fine. It is just not my preference.

-Kevin

Living the dream.

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Friday, September 4, 2020 11:43 AM

SeeYou190
One of the wargaming forums I used extensively had a button to hide posts from selected members. Once you could not see the troublemakers, everything became better. Once everyone set them to "ignore", they went away. That was a great feature.

At one time this forum had the 'friends' and 'foes' feature implemented, which as I recall would blank any posts from appearing to you from designated 'foes'.  (You could still read anything quoted from one in another post, though).

i am on a phone where that stuff doesn't work, but you might go into profile and see if that still works in the current klambake kludge.

  • Member since
    February 2010
  • From: Indiana
  • 225 posts
Posted by mikeGTW on Friday, September 4, 2020 11:39 AM

Mel quick question  so from what you are saying I can not run an engine anywhere in seperate blocks in opposite directions using common rail?

I use common rail (kind of)  and can run in opposite dir on my mains at the same time   So this should not work?    I have 5 throttles 3 hard wired and two on plugs  Not sure what I'm doing different but it works just fine

 

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, September 4, 2020 11:25 AM

RR_Mel
Please give me a bit of credit, I was very successful in electronics for over 50 years.  

Mel, you have nothing to prove, and please do not fall victim to the terrible turn that has happened lately.

There seems to be a trend among the argumentative set lately (those people that are quick to point out what you do wrong, but never share pictures of how they did it right) to shout down the experienced people that have good advice by using their big words and arsenal of incorrect information presented as fact.

Those of us with completed layouts (or like me, removed a completed layout and are in between at the moment), lots of experience, hands on knowledge, and a willingness to share/help, are under attack by the elite theorists and pro/am antagonists.

I am going to continue to share what I have learned, help out the curious, and hope people are sharp enough to filter out the confusion being presented.

One of the wargaming forums I used extensively had a button to hide posts from selected members. Once you could not see the troublemakers, everything became better. Once everyone set them to "ignore", they went away.

That was a great feature.

-Kevin

Living the dream.

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Friday, September 4, 2020 11:16 AM

Lastspikemike
At present we are using rail joiner power feeds everywhere which can of course cause the same problem as loose rail joiners elsewhere.  The price of convenience.  The trouble with soldering all the rail at the joints is changing your mind.

What I'd recommend is to get a good variable-temp soldering station with a tip temperature gauge, if you don't own one already, and then invest in several different melting points of solder and a good no-clean flux.  The solder to the joiners then is a type with higher liquidus ... in fact I'd consider a substantially higher liquidus ... than what you'll use in a joint.  If you change your mind about track later, you can just soak the joint to a temperature above its liquidus, suck the joint, and slide the connected joiner to one side. Continuity of feeders to the joiners remains happily good no matter how many times you solder or desolder the joints...

As noted in the other thread, effects of thermal expansion of rail runs are minimal on properly built track (as I think you indicated) and the occasional open joinered gap is simply handled with short bonding wire if not dedicated feeders.

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
  • 6,526 posts
Posted by RR_Mel on Friday, September 4, 2020 11:12 AM

 

I was attempting to answer the OPs question.  Read his post then you answer his question.

For over 60 years I have wired all my blocks with DPDT Center Off toggle switches so that in DC mode I could run two trains in different directions and it worked OK as long as I didn’t go into a opposite polarity block.

That will not work with common rail.

Please give me a bit of credit, I was very successful in electronics for over 50 years.  


Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 

 

  • Member since
    September 2003
  • 21,669 posts
Posted by Overmod on Friday, September 4, 2020 10:01 AM

Lastspikemike
What am I missing here?

His diagram is a counterfactual example -- it shows the improperly-wired condition 'as if' two packs were connected to a common-rail system.  Think of it as the 'Goofus' picture to a correct 'Gallant' isolated-pack wiring diagram... Smile

 

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!