Date   
Re: Wiring a Yard

Don Vollrath
 

It’s not that critical. One direction only. Estimate from beginning to end or Use a tape measure. 

DonV

Re: Offset Rail Gapping

PennsyNut
 

The only place where offsetting might be warranted is in curves where you do not solder. The better way is to solder all rails in a curve. In fact, even turnouts in a curve should be soldered to the track next to them. But as has been stated above, staggered joints don't really make a lot of sense. Just MHO.
Morgan Bilbo, about one year with very basic DCC

Re: Wiring a Yard

 

Thank you,
But what about the second part of the questions? How do we calculate the length of a track bus?
-Michael

Re: Wiring a Yard

wirefordcc
 

This topic is a good time to let new readers know about the work I did on track feeder size.  The results are on my website at:

http://www.wiringfordcc.com/track_2.htm#a14

There you will find a table of feeder sizes and feeder lengths that I tested .  My objective was to determine if a booster would trip or not.  I can definitely say do not use feeder sizes and lengths that are in the orange or red zones as your booster will not reliably trip.  

No matter what, after installation, short your track with a metal tool or object aka "the quarter test" to make sure your booster trips reliably.  Perform this test at the farthest point on a section of track from which the feeder attaches.  If its not going to work, you want to find out now.

Allan Gartner
Wiring for DCC

Re: Wiring a Yard

Jerry Michels
 

Michael,this is a great question.  I believe the length of the longest run is the answer.  Parallel busses should not affect the available power.

Jerry Michels
Amarillo Railroad Museum

Re: Offset Rail Gapping

Jerry Michels
 

Michael, As far as I know, it is a way to avoid having a weak point where track could shift/kink out of alignment, especially on curves.  If used at all, the offset can be small.  If your track is properly installed and securely glued down, I do not think on offset is needed.  Consider that in almost every situation, when track is attached to a turnout the joints are not offset.  That being said, we have not found a problem having an offset with DCC.  We have some old-school members who insisted on having offsets, but in truth have suffered no ill effects either way.

Jerry Michels
Amarillo Railroad Museum

Re: Wiring a Yard

Don Vollrath
 

Michael et al
If you are not providing isolated yard tracks with any power cut off switches then each track is merely another parallel path for the DCC power to flow.... just like that on the track rails. Don’t worry so much about the wiring underneath. Provide a single main DCC bus to follow the main/center layout of the yard tracks from end to end while continuing onto the mainlines. Use multiple 20 AWG track feeders to connect each yard track to the same DCC bus. (24 gauge is kinda small) solder rail joiners or provide track drops for each section of track. Allow for some rail expansion movement to prevent kinking.

Calculate DCC bus length as if it were a single conductor. Avoid forming it into a loop. Add an R/C snubber at the ‘open’ end far away from the booster.

DonV

Re: Offset Rail Gapping

whmvd
 

Michael,

I've read it too, and have followed several threads in various forums on this subject. I have never found an explanation for the practice that made sense to me, but people can get almost religious on this topic, so prepare for heated argument!

Wouter


On Sun, 22 Mar 2020 at 02:18, Michael Boyle <boyle10017@...> wrote:
Greetings,
I've read, and been told, to offset the rail gaps between power districts. What is the science behind this and do we do that everywhere (for example in a reversing loop)?
Thanks,
Michael

Re: Offset Rail Gapping

Don Vollrath
 

It’s hearsay BS. No science behind it. Never seen a case where staggered gaps are required when other recommended practices are Being followed. Put isolating gaps opposite each other. Fill the gaps so they cannot close by rail movement.
DonV

Wiring a Yard

 

Greetings (again),
I've got a yard that is about three feet wide. It has a ladder at both ends and a single track arriving and leaving. The track bus follows under the arriving track. Since I want to keep my 24AWG track feeder wires as short as possible I'm thinking of splitting the track bus in two. At the other end of the yard, do I bring the two busses back together or do I put a snubber on one, terminating it? How do I now calculate the length of the bus? If the split section is 20 feet long and the length of the bus on either side of the yard is a total of 40 feet, do I calculate the bus length as 60 feet (the accepted maximum) or have I effectively created an 80 foot bus? Which raises a related question: What is the effect of branching the track bus? Is the total length equal to the sum of the branches? Or is it just the length of the longest run? Are several splits worse than only one or two?
Thanks for your help, my education is far from complete (even at my advance years).
As always,
Michael Boyle

Offset Rail Gapping

 

Greetings,
I've read, and been told, to offset the rail gaps between power districts. What is the science behind this and do we do that everywhere (for example in a reversing loop)?
Thanks,
Michael

Re: Snubbers

Mark Gurries
 

If you want to go deeper on snubbers….go here.

https://sites.google.com/site/markgurries/home/dcc-general-best-practices/wiring-planing/snubbers-rc-filter <https://sites.google.com/site/markgurries/home/dcc-general-best-practices/wiring-planing/snubbers-rc-filter>


On Mar 18, 2020, at 7:18 AM, Jerry Kramer <@JKramer328> wrote:


No one has explained what snubbers are since this thread started.
Looks like I don't need them since my layout runs perfectly without them.
Sounds like people here like to make things complicated.
I run a double level layout with 28" high helix on DCC equipped KATO Unitrack with MRC Advanced Squared2 power. I usually run 3 to 5 engines at a time with no problems.
Jerry Kramer
Willamette Regional Railway

Sent from Xfinity Connect Application


Best Regards,

Mark Gurries
Electrical Engineer
DCC Website & NMRA DCC Clinics: www.markgurries.com

Re: Snubbers

george hohon3
 

I shouldn't laugh when people trip and fall down when they aren't watching where they're going, but I do.  I do the same thing when someone buys something for their railroad that will do "A" and then they try to make it do "A+1" and when it doesn't, they run back to the manufacturer or web sites like this one and ask for answers and fixes, or just to make complaints that the product "A" is crappie.

I know I shouldn't be laughing at you, but when you exceed the performance standard of the device, it's your fault and I do laugh.  And it seems like I'm laughing more than usual lately.

LG   


From: w4dccqa@groups.io <w4dccqa@groups.io> on behalf of whmvd <vandoornw@...>
Sent: Wednesday, March 18, 2020 7:23 AM
To: w4dccqa@groups.io <w4dccqa@groups.io>
Subject: Re: [w4dccqa] Snubbers
 
Jerry,

"Sounds like people here like to make things complicated."

No, people here give a lot of their time and put in a lot of effort to solve problems others encounter. The "I do not have this problem so it must be a myth" school of thought may work for you now, but if you make changes to your railway in the future and encounter strange behaviour (you may or may not) have a look back here.

The extremely cheap and simple electronic devices called snubbers (google "dcc snubbers" if you ever get interested, and you'll probably find Mark Gurries' topic on his invaluable site listed first) ensure that the digital signal put out by the command station or booster does not get damaged by incorrect (dcc bus) line termination, which an open end unfortunately invariably is. The longer the bus run, the more likely complications arise. Feel free to ignore. But being disparaging isn't helpful to anyone.

Wouter

On Wed, 18 Mar 2020 at 14:15, Jerry Kramer <jkramer328@...> wrote:

No one has explained what snubbers are since this thread started.
Looks like I don't need them since my layout runs perfectly without them.
Sounds like people here like to make things complicated.
I run a double level layout with 28" high helix on DCC equipped KATO Unitrack with MRC Advanced Squared2 power. I usually run 3 to 5 engines at a time with no problems.
Jerry Kramer
Willamette Regional Railway

Sent from Xfinity Connect Application



Re: Snubbers

whmvd
 

Jerry,

"Sounds like people here like to make things complicated."

No, people here give a lot of their time and put in a lot of effort to solve problems others encounter. The "I do not have this problem so it must be a myth" school of thought may work for you now, but if you make changes to your railway in the future and encounter strange behaviour (you may or may not) have a look back here.

The extremely cheap and simple electronic devices called snubbers (google "dcc snubbers" if you ever get interested, and you'll probably find Mark Gurries' topic on his invaluable site listed first) ensure that the digital signal put out by the command station or booster does not get damaged by incorrect (dcc bus) line termination, which an open end unfortunately invariably is. The longer the bus run, the more likely complications arise. Feel free to ignore. But being disparaging isn't helpful to anyone.

Wouter


On Wed, 18 Mar 2020 at 14:15, Jerry Kramer <jkramer328@...> wrote:

No one has explained what snubbers are since this thread started.
Looks like I don't need them since my layout runs perfectly without them.
Sounds like people here like to make things complicated.
I run a double level layout with 28" high helix on DCC equipped KATO Unitrack with MRC Advanced Squared2 power. I usually run 3 to 5 engines at a time with no problems.
Jerry Kramer
Willamette Regional Railway

Sent from Xfinity Connect Application



Re: Three Rail Layouts

whmvd
 

Hi Carl,

I just had an 'OutOfComprehension' error. If you have three-rail, what are the auto-reversers for? Three-rail solves the problem of polarity clashes very neatly, I thought?

Wouter


On Wed, 18 Mar 2020 at 16:16, Carl <carl.blum@...> wrote:

Hello Allen:

Your website asks to let you know if anyone is running a three rail layout. I have since 2002, it has taken 3 major re-wirings to work well with DCC, and an optional switch to Lionel AC. The biggest problem I have is with the Auto-Reversers on the booster. If I have a common short the Auto-Reverser kicks in and the polarity is wrong at the next gap. I've tried to turn the option off, but it doesn't seem to help. So I have rewired again, with manual reverse switches so I can cancel out the Auto-Reverser.

I'm happy to answer any other questions.

Thanks, Carl.

https://www.facebook.com/charlestonmag/videos/300992497192775?sfns=0

PS: Lionel is not just for Christmas Trees.

Re: Snubbers

wirefordcc
 

Hi Jerry,

If you want to know what a snubber is, visit my website at:  http://www.wiringfordcc.com/track_2.htm#a47

Allan Gartner
Wiring for DCC

Re: Snubbers

mgj21932
 

Yup. You got it Dale.

Allan’s information is incredibly informative. 

That said, the exchange on this group is most enjoyable — especially as we isolate in place.  

Bill D 


On Mar 18, 2020, at 11:46 AM, Dale Gloer <dale.gloer@...> wrote:

The wiring for DCC website answers all your questions about snubbers.  Here  is the link
http://www.wiringfordcc.com/track_2.htm#a47

They are only needed in situations where you have a long track bus - long being generally more than 30 feet.  If your layout is running fine without any snubbers then you don't need one!

Dale Gloer
Layout Supervisor, Southern Alberta Model Railway Club

Three Rail Layouts

Carl
 

Hello Allen:

Your website asks to let you know if anyone is running a three rail layout. I have since 2002, it has taken 3 major re-wirings to work well with DCC, and an optional switch to Lionel AC. The biggest problem I have is with the Auto-Reversers on the booster. If I have a common short the Auto-Reverser kicks in and the polarity is wrong at the next gap. I've tried to turn the option off, but it doesn't seem to help. So I have rewired again, with manual reverse switches so I can cancel out the Auto-Reverser.

I'm happy to answer any other questions.

Thanks, Carl.

https://www.facebook.com/charlestonmag/videos/300992497192775?sfns=0

PS: Lionel is not just for Christmas Trees.

Re: Snubbers

Dale Gloer
 

The wiring for DCC website answers all your questions about snubbers.  Here  is the link
http://www.wiringfordcc.com/track_2.htm#a47

They are only needed in situations where you have a long track bus - long being generally more than 30 feet.  If your layout is running fine without any snubbers then you don't need one!

Dale Gloer
Layout Supervisor, Southern Alberta Model Railway Club

Re: Non-terminal snubbers

Carl
 

Hi Gang:

Since we are mostly stuck at home, now would be a good time to finish projects! And if you are willing to write the magazines are always looking for material.

Carl.

On 3/17/2020 6:34 AM, Daniel Brewer wrote:
@Allan please use my question if it is good for your column. I’m looking forward to reading it.
Dan
Granger, IN