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HOW do you block a DC layout?

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Posted by JimKay on Thursday, August 4, 2016 11:05 PM

Hello: I am from the old school I run DC. I usually block 6 to 8 real feet on each main line. On my present layout I am using 3 power supplys. How ever long your blocks are, you have to insulate the front and the rear of the block. I use plastic rail joiners. Than if you are on main line 1 you have to connect a power supply to that block. Now you have to break the power connection with a switch, your choice. When you want to switch from  main 1 to main 2, you leave the turnout stright thru but you must insulate the switch where it goes into main 2 again useing plastic rail joiners. I am running 25 engins and 500 rolling stock including passenger trains. My main line 1 is 100 real feet long, it has 8 blocks, there is signaling at each block. I have 50 turn outs on the layout including 3 way, double cross overs, and double slip switches. I switch between lines 1,2,3 all of the time. Just remember insulate front and rear of each block, turnouts when switching from 1 to 2 and in my case 2 to 3 and dont forget you must power each block with a switch to control the power. By the way I can run 8 engins on each track at one time. Also when you run your power wires, bring back +/- to a central point. Make sure you dont get the wires mixed up with the other power supply. My e-mail jameskrawiec2@verizon.net

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Posted by richg1998 on Sunday, July 31, 2016 12:31 PM

A resurrected thread. Got to love it.

Back in the early 1980's our club wired a layout using the common rail approach with fourteen blocks and one reverse loop. Wow, time's fun when you are having flies.

A single DPDT switch for the reverse loop and a bunch of SPST switches for blocks. Used the wiring book from Kalmbach I believe.

We used #24 telephone wire because the club president worked for telephone company.

Four throttle capability. We needed a dispatcher at the control panel. “Who's got my loco” was a common question when the dispatcher was gabbing.

Most times, one loco unless someone had a couple locos that matched well under DC.

With DCC, all blocks turned on and reverse switched ignored.

DC ampmeter and voltmeters no longer worked.

Made a DIY DCC ampmeter and used a cheap digital voltmeter for track voltage. NCE Power Pro shows about 13.6 VAC as I last recall.

A large red LED meter shows DCC current and can be easily seen anywhere in the room.

Had to finally install #14 wire for feeding the layout.

Some like the EZ Command for simplicity as compared to DC for only a couple locos and one DC only loco can be used but that is another issue. Some just do not count all the rivets.

Downside, no modification of CV's and last I knew, you cannot do a decoder reset. You can program the loco number but this system is old school but cheap enough on ebay.

You can control nine sounds on sound equipped locos.

Some still use the system as I have seen in the Bachmann forums.

I use the NCE Power Cab which does not run DC locos. I switch systems but that is rare anymore.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by jjdamnit on Saturday, July 30, 2016 10:32 PM

Hello all,

SUX V R40 Rider
Yes, DCC is out of the question right now. Mainly because of the expense.

I would seriously consider DCC.

After purchasing the controllers and switches; either Single Pole Double Throw (SPDT) or Atlas Controllers, and the accompanying footage of wire, you will find that the most basic of DCC systems will serve you better. And cheaper.

As Cody Grivno says, "Don't ask me how I know this, I just know this."

Bachmann makes an extremely simple and inexpensive system know as EZ-Command. (Add snarky comments from other DCC users here.) Ignore the MSRP from Bachmann and look at eBay for deals on this system.

On a 4'x8' simple pike you can get away with one set of feeder wires to achieve your goals of two- or multi- cab operation.

That means, rather than buying and installing literally tens-of feet of wire you can cut that down to a few feet of wire from the controller to the track. Which, is included in the EZ-Command set.

The only other expense is wiring your existing DC locomotives with DCC decoders.

If you have the knowledge and tools to wire a DC pike, installing simple DCC decoders in your existing motive power can be easily done.

However, if you insist on wiring your pike for dual-cab DC operation then I would consider purchasing the Atlas book; The Complete Atlas Wiring Book. This publication not only explains multi-cab control but also is a great primer for turnouts, reverse loops, etc.

Hope this helps. 

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by rrinker on Saturday, July 30, 2016 1:56 PM

It does change exactly as you think, but the only 'conflict' is between the non-common wires from each power pack. Between the common side and any one of the power packs, you are simply changing the polarity and reversing the train. You need a complete circuit for any current to flow - hooking the _ of one power pack to the - of the other, as happens in common rail if one is set to forward and one is set too reverse, does not make any current flow between the two.

 Let's say they are both on full throttle and htey put out 12 volts. If the common side os - on both packs, thus the free wire from each pack is the + side, you would measure 0 volts between the free wires, but between either free wire and the common wire you would get 12V. If you now flip the direction switch on just one of the power packs, you now have a - on one free wire and a + on the other. If you measure across the two free wires, you will now have 24 volts - this is just like 2 batteries in series. But between the common and any one of the free wires, it will still be 12 volts.

 The only possible place you could have a problem is if you run a train across the gap where one side is controlled by one pack and the other side is the other pack, and they are set for opposite direction. The voltage across the gap is the 24 volts in this situation and if a loco coasts past the gap you could have a 24V short circuit going through the wire that connects the front pickup to the rear pickup.

                     --Randy

 


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Posted by passenger1955 on Saturday, July 30, 2016 1:23 PM

I was just looking at this old diagram you posted (thank you). Can you please help me understand something about the common rail? When someone flips the direction switch on Power Pack Cab A (so that block can run in reverse) my expectation is that the polarity would switch, and the terminal connected to the common rail would switch from (for example) positive to negative, which might conflict with the polarity in Power Pack Cab B. Obviously it doesn't (or you wouldn't have posted this diagram). Can you please help me understand why having the power packs switch polarity in a common rail setup isn't a problem?  Thanks.

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Posted by SUX V R40 Rider on Thursday, November 29, 2012 11:33 PM

I'll post some photos soon. Right now I am working n drilling holes in the wood deck large enough to feed the square shaped connectors through that plug into the EZ track terminal rerailers and the remote for the turnout. The existing wiring I am using is at the point of needing to run it under the table, instead of across the top of the island and under the track bed. All of the holes are drilled. I just need to clean up the saw dust, put the track back together and add the trains to it.

I am not worried about how many holes I have drilled and the fact that they are so big. Eventually the deck will be covered with the 2" pink or blue insulating board. This will have holes drilled into it that will line up with the holes in the wood deck. Covering the insulating board will be a scenery mat that will be the appropriate color for what I am running at the time. This mat will have slits cut in it to allow the square connectors to feed through to connect to the rerailers and remote for the turnout. What little wiring is exposed will be hidden by something in the scenery.

No I am not planning on fastening down the EZ track because it has to be able to be easily taken apart to be changed or taken apart for transport.

As the switching becomes more complex I have figured out near the corner of the layout just on the outside of a radius corner of the oval will be too small to leave the power packs sitting, especially when I add more switches. For now I am going to use an old desk to sit the power packs on along with switches as they are added. I will mount the switches and the one power pack to a board and clamp it to the desk. this will work until I can build a control table with folding table legs to sit at the end of the layout. All of the wiring, no matter where it is connected to on the layout will end up connecting to something on the control table. I will build this as I need it, which will be as the amount of switching becomes more complex.

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Posted by rrinker on Thursday, November 29, 2012 8:15 PM

 Yes, it should work as you describe. That's why you use the DPDT center off toggles - so a given section of track can be connected to pack 1, pack b, or off completely. So you can park a loco by setting the switch for that track to off, set the switch for the main to pack a, and run the train with A. Once clear of the yard lead, you cna set the switch for the siding and yard to B, and run that loco with pack B.

 Excact placement of isulated joiners and feeds is going to depend on the actual track layout. Do you have a plan of what you're building? Hand drawn and scanned, computer drawn, even a phot showing the whole thing, would be helpful.

            --Randy

          


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Posted by maxman on Thursday, November 29, 2012 2:41 PM

There have been some good suggestions, along with a couple good sketches.  What you really need is to get one of the wiring books.

If you don't want to get a book, I suggest the following link to an NMRA article called Basic Track Plan Expanded and how to wire it: http://www.nmra.org/beginner/extended.html.  It shows a layout that sounds similar to what you seem to have, as there is a loop with a small yard attached.  It is wired for dual cab control, which is what you would have with your two transformers.  It uses toggle switches instead of the Atlad products.

The only thing I don't like about it is that it is common rail, hence the single pole/double throw switches.  If it were me, I'd use double pole/double throw toggles, where both wires from the transformers go to the toggle switches, and then go to the rails.  However, this is a matter of preference.

If you study the diagram, you'll see that either engine can be parked any place if you don't want it to be running.  Or you can run them independently of each other so long as you don't cross from one block boundary into a block where the other engine is operating.

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Posted by SUX V R40 Rider on Thursday, November 29, 2012 12:30 PM
If i use the correct toggle or selector switch to isolate a pull off siding to spot the road loco. on and set the switch to off while the yard unit is sporting cars on the mainline with the mainline operated by power pack A will this work as i described in my previous comment?
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Posted by SUX V R40 Rider on Wednesday, November 28, 2012 11:00 PM

Randy, I wasn't thinking of a simple on and off switch going from each power pack going to the same section of track.

I was thinking of:

  1. Using the first siding as the pull off for the road unit, with or without cars attached, connected to power pack A along with the mainline also connected to power pack A at the same time. the difference is the pull off will be isolated with wiring going to a separate on/off switch. When necessary I pull the road loco. into the pull off and turn its switch to off, but the mainline still has power to it. Only the pull off siding is turned off.
  2. All of the other sidings are operated by power pack B. These make up the yard. It is within the yard where the GP loco. is primarily operated until it needs to enter the mainline to spot cars to be connected to the road loco.
  3. After the GP unit is finished spotting cars on the mainline it retires back to the yard. The switch that has the pull off siding turned off is set to on and the road unit rolls onto the mainline, connects to the cars and off it goes around the mainline.
  4. While the road unit is hauling around the mainline I can still operate the yard loco. to spot cars where needed on the sidings, as long as I do not travel over the turnout that is blocked using the insulated rail joiners.

What do you think of this?

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Posted by rrinker on Wednesday, November 28, 2012 10:29 PM

 What you do NOT want is a simple on.off switch from each power pack going to the same section of track. This will work - up until you forget and turn both on at the same time. If it doesn't matter that the isolated section is always controlled byt he same power pack when turned on, you can use somethign like the Atlas Connector which is simply 3 ganged on/off switches - the power pack connects tot he side, and across the top are pairs of connections that go to each track section. Like the Selector shown for dual cab control, you can chain multiple Connectors together if you need more than 3 sections.

 But this won't be enough if you really want to have the two power packs and control multipel trains. It simply cannot be done other than with either the Selector feeding eacha nd every isoalted section, or DPDT toggles to avoid the common rail wiring. If you use the Connector, and have tracks 1-3 controlled by Pakc A< and tracks 4-6 controlled by Pack B, sooner or later you will need to move a train on track 2 from pack B, and that won;t be possible with a setup like that. Witht he Selector type of setup, you cna control any section of track from either pack, at any time.

By now DCC ought to be looking awfuly simple. No insulated joiners, just have a few terminal sections all wired in parallel (2 wires alone won;t cut it, rail joiners stink for long term electrical connections, so a few extra feeders will make everything more reliable). Then you can run any train anywhere, stop anywhere, even run one up to the tail end of the stopped train and pluck cars off it for switching.

               --Randy


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Posted by SUX V R40 Rider on Wednesday, November 28, 2012 10:12 PM

rrinker

 You're going to have to go with the extra switches. If not the Atlas components (I've never been a fan of common rail wiring anyway), you can use DPDT center off toggles. One side goes to pack A, the other side to Pack B, and the center terminals to the track. You will need to isolate some sections - for a yard a better track arrangement would have an extra track off the main as an arrival/departure track, the road loco would pull in there, uncouple, and go elsewhere, then the yard engine could come out and grab the cars and sort them. Each section of track could then be connected to either pack A, pack b, or turned off so a loco sitting there won't move at all.

 Please do pick up a book like Basic Model Railroad Wiring which will explain and diagram all this stuff.

           --Randy

 

Randy, I will pick up the book.

But I think what you're describing is build in a section of track to pull the road loco. into that is connected to a selector switch, such as Atlas, and turn off that section of track, via the selector so it is isolated from the rest of the operational layout until the GP unit is finished spotting cars. Then when finished and the GP loco is back in the yard, turn on the isolated section and run the SD loco. connected to the cars it is hauling around the main oval. With building in this section it will not matter what power pack it is connected to because the selector will have on and off switches.I am thinking I could also isolate a section of the mainline into a selector switch as well that could be powered on and off as needed when the road loco. is spotted on it.

Is this kind of like taking a lamp that has its own power switch and hard wiring it into 2 wall switches, one at opposite ends of a room as well? This way it doesn't matter which wall switch is on, if the power switch on the lanp is not set to on it will not work until it is. BTW I have actually wired a floor lamp to do this.

Am I far off from what you describe?

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Posted by rrinker on Wednesday, November 28, 2012 9:30 PM

 You're going to have to go with the extra switches. If not the Atlas components (I've never been a fan of common rail wiring anyway), you can use DPDT center off toggles. One side goes to pack A, the other side to Pack B, and the center terminals to the track. You will need to isolate some sections - for a yard a better track arrangement would have an extra track off the main as an arrival/departure track, the road loco would pull in there, uncouple, and go elsewhere, then the yard engine could come out and grab the cars and sort them. Each section of track could then be connected to either pack A, pack b, or turned off so a loco sitting there won't move at all.

 Please do pick up a book like Basic Model Railroad Wiring which will explain and diagram all this stuff.

           --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

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Posted by SUX V R40 Rider on Wednesday, November 28, 2012 9:17 PM

The Athearn GP50 runs great on the layout. It is cold outside and after I  unpacked it I let it warm up to room temperature. Then I ran it at various speeds going forward for about 20 min. or so then at various speeds in reverse for about 20 min. around the oval. After that I replaced the metal rail joiners with insulated ones on both rails. Remember I am running Bachmann EZ Track, not continuous track where only one side has to be gapped. One one side of the insulated joiners is the turnout and on the other is the new 9" terminal rerailer. The new rerailer is connected to power pack B.

I then tested both locomotives, separately,  with both power packs set to the same direction and it works great. I tested  it in both directions.

So for right now the one and only siding I have is operated by power pack B and the remote turnout and mainline is operated by power pack A.

But I already see a minor issue that could turn into a source of frustration as I build more sidings into the yard. That is when I need to spot cars on the mainline with the GP loco. for the SD loco. to haul I think I am going to have to literally and pick up and remove the SD loco. off of the track by hand. Or do the same with the GP loco.

 I already know I won't have a problem with spotting cars on the various sidings within the yard while the SD hauling its load around the mainline because it is separated or blocked from one another with the insulated rail joiners. But once the GP loco. starts to spot cars on and off the mainline, if the SD loco. is sitting there it is going to be an issue.

Any ideas on how to stop the SD and have it sit idle until I am finished spotting cars with the GP unit without using DCC?

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Posted by floridaflyer on Wednesday, November 28, 2012 2:31 PM

Randy, that was my initial suggestion in the first response to the OP.  Using the Atlas selector is an upgrade but in the initial post he wanted to run one loco on the loop and the other one in the yard. Our suggestion is the simplest, yet gets the job done.

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Posted by fwright on Wednesday, November 28, 2012 1:32 PM

SUX V R40 Rider
What if for right now i want to avoid the atlas selector? Remember i am using Bachmann ez track with terminal rerailers where needed. As i described i am going to connect either 9inch terminal retailer to the turnout and this is where the plastic rail joiners will be used. Or right after the curve use a 9 inch straight terminal retailer.

The turnout which is connected to the mainline will be operated by power pack A. The terminal rerailer used as the entrance, after the remote turnout, to the siding will be operated by power pack B. Ever turnout and siding connected to the first will likewise be operated by power pack B.

You really don't want to do what you are proposing.  What you are suggesting - one power pack controls one area of the layout, and the other controls another area - is called section control, not block control.  Section control has several flaws in comparison to block control:

  • you are changing which power pack has control as the train moves from section to section.  This means you have to get the direction settings the same, and the voltage controls very close - every time a locomotive crosses the boundary.
  • Because you can't get a perfect match between the 2 power packs, and because metal wheels bridging the gaps tie the 2 power packs together momentarily, there will be lurches as a train crosses the boundary.
  • When metal wheels bridge gaps at the section boundaries, both power packs are momentarily connected to the same section of track.  There is a feedback current from one power pack to the other through the metal wheels.  The feedback current is proportional to the voltage difference between the two power packs, with a low resistance path.  It can be qutie high.  The overload limiter on the power pack may or may not protect against this feedback current.

Please do not use section control on a small layout.

Block control insists that the same power pack control its train wherever it goes on the layout.  Block control normally has one power pack connected to both sides of a block boundary, so there is no lurching or feedback current.  To use block control, you do need a toggle switch or Atlas Selector slide switch for each block, as Jim showed in his beautiful diagrams.

Yes, you will have to cut the wires from the Bachmann terminal strips before they reach the power pack, and tie them to the block toggle or Selector.  Yes, you will need a Bachmann terminal track in each block of the layout.  Or you can use Atlas rail joiners with wires attached instead of the Bachmann track terminals.  As you gain more experience, you can solder your own wires to rail joiners or rails.

hope this helps

Fred W

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Posted by SUX V R40 Rider on Wednesday, November 28, 2012 12:48 PM
What if for right now i want to avoid the atlas selector? Remember i am using Bachmann ez track with terminal rerailers where needed. As i described i am going to connect either 9inch terminal retailer to the turnout and this is where the plastic rail joiners will be used. Or right after the curve use a 9 inch straight terminal retailer.

The turnout which is connected to the mainline will be operated by power pack A. The terminal rerailer used as the entrance, after the remote turnout, to the siding will be operated by power pack B. Ever turnout and siding connected to the first will likewise be operated by power pack B.
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Posted by Soo Line fan on Wednesday, November 28, 2012 10:19 AM

 

SUX V R40 Rider

After reading the great sources of information provided I am thinking of trying this

I will likely have to use a barrier strip because only so many spade connecters can be attached to the power pack.

 

No need for a barrier strip at this this time. The Atlas Selector is your barrier strip. The spades attach to the terminals across the top. Note only one wire is attached to each terminal of the power packs in the drawing.

The selector or a toggle switch is required, not optional.

SUX V R40 Rider

I am asking what happens to the locomotive when it is straddling this gap or rail joint until both sets of wheels are either completely on the siding power by power pack B or on the part of the switch that is connected to the mainline/oval/outside loop which is operated by power pack A.

My biggest concern is if this is hard on the motors, even with the power packs set in the same direction and close to the same speed.

Not a concern, you may notice a momentary surge or slow down as it crosses the gap.

If the packs are in opposite directions, the engine will sit over the gap. Depending on the settings and design of the packs, a breaker may open until the direction mismatch is corrected. Or the engine may sit over the gap and "hunt" back and forth. If this happens shut down one of the packs ASAP.

SUX V R40 Rider

This almost sounds like a hand off type application, where for maybe a second or 2 half the loco is powered by one power pack and the other half powered by the other until the hand off is complete where the entire thing is operated by only one power source.

Am I on the right track here, or am I still missing something?

Some what.

When operating, you set both your circle and spur to cab A using the selector.

Using cab A, you proceed into the insulated spur. Cab B is not being used.

Once clear of the gap, you can swich the selector to cab B. Now the circle is still powered by A and the spur by B.

The hand off as you call it is done, or should be done after you pass a gap, not before. When done using the above method, the engine does not momentarily become powered by A and B.

Jim

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Posted by SUX V R40 Rider on Wednesday, November 28, 2012 12:05 AM

There is no inside loop. The inside of the oval will be the yard ladder connected to the oval, or outside loop. It is at the first turnout that connects to the first siding, and right now my only siding, that will have the plastic rail joiners and gap.

I am asking what happens to the locomotive when it is straddling this gap or rail joint until both sets of wheels are either completely on the siding power by power pack B or on the part of the switch that is connected to the mainline/oval/outside loop which is operated by power pack A.

My biggest concern is if this is hard on the motors, even with the power packs set in the same direction and close to the same speed.

This almost sounds like a hand off type application, where for maybe a second or 2 half the loco is powered by one power pack and the other half powered by the other until the hand off is complete where the entire thing is operated by only one power source.

Am I on the right track here, or am I still missing something?

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Posted by rrinker on Tuesday, November 27, 2012 11:33 PM

 For what you say you want to do, switch on the indie loop with one loco and run the other on the outside loop, there is a simpler way. Just gap the rails connecting the inner and outer loops, connect 1 power pack to the outside loop, and one power pack to the inside loop.

 You can still move from one loop to the other - just make sure both power packs are set for the same direction and close to the same speed so there isn;t a sudden jolt crossing from one to the other.

 

             --Randy

 


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Posted by SUX V R40 Rider on Tuesday, November 27, 2012 10:40 PM

Here is some more detail on my layout, I need to describe this before I advise what I am going to try. Remember I am using Bachmann EZ Track.  So far I only have one turnout connected to the mainline that the only current siding is connected to. At the end of the switch section of the track is a 18" radius curve to reverse the direction, then the long straight section with a Hayes bumper at the end, this makes up this siding. The reverse curve is so the straight section is parallel to the straight section of the of the main line which is right next to the siding. Eventually there will be more and more sidings as I build the yard ladder.

After reading the great sources of information provided I am thinking of trying this:

  1. Where the reverse curve connects to the turnout use plastic rail joiners and if necessary cut a very small gap so the rails do not touch, preventing current from traveling into this section of the siding from power pack A. This turnout has a remote and will be operated by power pack A.
  2. Right after the reverse curve have a 9" straight terminal rerailer connected to power pack B to provide power to this part of the siding. (I could use a 9" radius terminal rerailer for the reverse curve if I wanted to as well.)
  3. as I connect more turnouts to the first one to build the yard ladder each one will have a terminal rerailer connected to power pack B.
  4. I will likely have to use a barrier strip because only so many spade connecters can be attached to the power pack.

I do have some more questions about this application. First from what I have read, this will work, correct?

I know when a locomotive is traveling over the rail join with the plastic joiners and small gap both power packs have to be set in the same direction. But when the locomotives travels over the gap where the plastic rail joiners are being used and with both trucks having power to them when the loco. is straddling this section is one truck being powered by power A and the other by power pack B until it completes traversing this section and both sets of wheels are either completely on the siding powered by power pack B or on the switch which is powered by power pack A along with the rest of the mainline? If this is how it operates is this hard on the motors even if the speed of the power packs is turned down, but still won't match each other exactly?

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Posted by tstage on Tuesday, November 27, 2012 10:07 PM

[Contents deleted.  Posted in the wrong thread. Embarrassed]

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Posted by Soo Line fan on Tuesday, November 27, 2012 9:11 PM

SUX V R40 Rider
When I have asked the question of how to run two locomotives on a DC powered layout I get the same answer: "block it", but no one elaborates on how to do so and I have gotten no where on how to do so. Well now I am asking: HOW to block it? I need some type of easy to understand/read  diagram or other reliable resource to look at that will show me how to do this.

Here is a drawing I created to give you an idea. The layout is a simple circle of track with one siding.

The inner rail is left without any gaps and is called a common rail. As you can see, both packs are connected to it directly via the black wire.

The outside rail is cut into sections called "blocks" using either an insulated rail joiner or a thin cut to form a "gap". Power is supplied from either pack by routing the red wire to the Atlas Selector and then on to the outside rail.

Refer to block 1:

If the Atlas selector switch is in the top position, power is provided by the power pack on the LH side, "Cab A".

If in the center position the train is shut off because no power is routed to this area.

If in the lower position, power is provided by the "Cab B" power pack.

Block 2 controls the siding. A train can be parked, or powered with either pack while on it.

If all the blocks are in the A or top position, the LH pack controls the entire layout.

fwright was dead on about the DC lowdown. All you need is a spool of wire, an Atlas selector or two, a good Atlas book and a second power pack. Very inexpensive and easy.

Many people get into this hobby and unfortunately, some do not stay for whatever reason. I always recommend that new uses start out slowly.

BTW, my layout is a 4x8 which uses 2 DC cabs and 4 Atlas selectors and I am very happy with it.

Jim

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Posted by UPinCT on Tuesday, November 27, 2012 8:04 PM

Don't get flustered get educated.  What works for me might not work for you.  I agree with Fred, you need to do more reading.

This is by Andy Sperandeo  and discusses basic DC wiring with an introduction to DCC 

http://www.amazon.com/Railroad-Wiring-Second-Edition-Railroader/dp/0890243492/ref=sr_1_1?ie=UTF8&qid=1354067210&sr=8-1&keywords=HO+Dc+Wiring

This book explaining DC wiring with the use of Atlas products has been around for over 50 years

http://www.amazon.com/Atlas-Model-Railroad-Complete-Wiring/dp/B0006KSLE6/ref=pd_vtp_b_6

Check out Tony's for the FAQs on DCC

http://tonystrains.com/tonystips/dccprimer/index.htm

And Finally from our hosts you can download some PDF's on model railroad wiring

http://www.kalmbachstore.com/modeltrains-railroading-model-railroading-digital-downloads-downloadable-articles-dc-wiring-and-digi.html

EDIT: BTW I upgraded to DCC a few years ago and haven't looked back

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Posted by tstage on Tuesday, November 27, 2012 5:14 PM

The Athearn GP50 should have an 8-pin plug or socket (2 rows of four) but you'll have to remove the shell to double-check.  Worse case is that you'll have to hard-wire the decoder, which isn't all that difficult if you're handy with a soldering iron.

More than likely the SD40-2 will not have the NMRA plug.  However, as long as the motor is isolated from the frame and you have room under the hood, you can hard-wire a decoder into it.

Tom

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

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

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Posted by SUX V R40 Rider on Tuesday, November 27, 2012 1:47 PM
One of my locomotives is a Mehano SD40-2 manufactured in about 1996. The other is an Athearn GP50 manufactured in about 2008.

Should both locos. have the ability to add a decoder chip in them, where it is unplug/plug and play or cut and splice wires together?
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Posted by fwright on Tuesday, November 27, 2012 1:27 PM

SUX V R40 Rider
Yes, DCC is out of the question right now. Mainly because of the expense. I have had enough frustrations with not receiving complete information or receiving inaccurate information from sources i thought i could trust along with other challenges with building this small layout. It almost got to the point where i was ready to peak it in, cut my loses and give up on this me hobby altogether. I don't need to add to the frustration of trying to work with DCC right now until i get more experience with what i have.

You have already received misleading information in this very thread about DC block control.

First, I'll address the question of DC vs DCC.  For the specific scenario you describe - one train circling an oval on autopilot on a 4x8 while another switches the yard or spurs while mostly staying clear the autopilot train - control of both trains by one person is problemmatic no matter what control system you use.  How long does it take for the train to make a lap on the oval?  How many minutes or seconds between needs for the main by the switcher?  What I am trying to point out is that your operational scenario may be impractical - but that depends on the actual track plan.

The big advantage of DCC is being able to operate mulitple trains on shared trackage without worrying about blocks and getting blocks selected.  How important this flexibility is depends on how often the switcher needs to share or use the main.  The other advantage of DCC is the ability to really use and enjoy sound-equipped locomotives down the road.

Cost - since you already have the 2 power packs for DC - is going to hinge on whether or not you want a second DCC throttle for a second operator.  For one person operations, the $160 Power Cab or a Zephyr is sufficient.  The second throttle is going to push you close to $250 total.  DC might cost you another $20 - $40 in block controls and a book on wiring.  If you want walk-around DC throttles with smoother control of your engines than a train set power pack, you will probably spend $40 per throttle (or MRC Tech power pack).

The rest of this post assumes you have decided to remain with DC.  Run, don't walk, to your hobby shop or train show and get a book that discusses DC block wiring.  A used, older book like Westcott's will do just fine.  If you want to use the Atlas electrical products, Atlas has a wiring book on how to use their products.  Note that the Atlas Selector (you will probably need 2-3, no Controller needed unless you have a turntable) can be replaced with 4 SPDT center off toggle switches.

The underlying philosophy of DC block control is that you use the same power pack or throttle to control the train wherever it goes on the layout.  The blocks - electrically isolated sections of track - use a toggle (or slide on the Selector) to choose which power pack or throttle is connected to that block of track.  By sequentially choosing throttle A as train 1 goes from one block to the next, throttle A controls train 1 at all times.  To keep the train in continuous motion, both the block the train is in and the block the train is about to enter must have throttle A selected.  All other blocks can be off or given to throttle B for train 2.

From the above description, you need at least 4 blocks on the oval for two trains to chase each other under separate control.  At the same time, operations are much easier if a block is longer than your normal longest train (they won't always be).  Passing tracks become their own block.  Spurs capable of holding a short train should probably be a separate train as well.  A small yard (with its yard lead) is often wired as a single block because of the difficulty in having more than one locomotive in the yard at a time.

The wiring book will explain this in much greater detail with some helpful diagrams to allow you to understand what you are doing.

The blocks are created by installing insulated rail joiners or cutting gaps in the rail at the block boundaries.

my thoughts, your choices

Fred W (still using DC at home)

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Posted by BroadwayLion on Tuesday, November 27, 2012 12:31 PM

SUX V R40 Rider

With DCC doesn't every thing that runs on electricity HAVE TO BE decoded? Whether it is a turnout with a remote to every locomotive operated on the layout?

With adding decoders to the locomotives doesn't the interior of the loco. have to be able to house the decoder and have it correctly connect to the motor?

No, you only need to use DCC for your locomotives. You *can* do more, but everything else is just an elaboration on a theme. You can do it but you do not need that. Keep your switches simple!

No, these DCC chips are quite small, most newer locomotives already have a PC board with a place to plug in the DCC chip. On my subway cars, there is a dummy pluck to remove, and to plug in the DCC thingie.

That said, I only have one LION and want to run eight trains at once. Thus I have built something different.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by tstage on Tuesday, November 27, 2012 12:30 PM

SUX V R40 Rider

With DCC doesn't every thing that runs on electricity HAVE TO BE decoded? Whether it is a turnout with a remote to every locomotive operated on the layout?

No, it doesn't.  You can operate your turnouts just like you do with DC.  Or, you can operate them with ground throws.  If you want to you can operate your turnouts via your DCC throttle but it isn't necessary.  Personally, I would find that too cumbersome and would prefer either manual ground throws or switch machines run on a separate electrical bus.



With adding decoders to the locomotives doesn't the interior of the loco. have to be able to house the decoder and have it correctly connect to the motor?

Yes, but with many of the newer locomotives, this can be as simple as a plug 'n play install using a NMRA 8-pin plug or socket that comes with the locomotive.  Lights, motor, and track picks are all  conveniently hooked up through the NMRA connection.  If room is tight (like with my Walthers SW1 switcher), you can often use smaller decoders (e.g an N- or Z-scale) inside a HO locomotive.

For steamers, there's usually plenty of room in the tender.  With diesels, it really depends on the size of the locomotive.  With your SD and Geep, I'm sure there would be plenty of room for  a decoder.  Depending on the model, there may even be a drop-in decoder.

Tom

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

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

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