SeeYou190 ATLANTIC CENTRAL Paul Mallery's Electrical Handbook vol 1 & 2, enough theory so you can advance, without boring you silly. Covers the basics, and starts you on the advanced path if you are interested. I bought both of these books based on your description. While everything you said about them is absolutely true, I think they are a bit much for someone just wanting to learn basic DC wiring. They are way beyond what the OP said he was looking for. crossthedog My question is which book about wiring a layout you would consider the EASIEST TO UNDERSTAND, like an idiot's guide. Not the most complete, not the one with the sweetest schematics, and not the one that goes into the most detail about outlying scenarios that I probably won't be pursuing... but the one you would consider most easy to grasp for someone electronically challenged but that still covers essentials for basic wiring of a DC layout. -Kevin
ATLANTIC CENTRAL Paul Mallery's Electrical Handbook vol 1 & 2, enough theory so you can advance, without boring you silly. Covers the basics, and starts you on the advanced path if you are interested.
I bought both of these books based on your description.
While everything you said about them is absolutely true, I think they are a bit much for someone just wanting to learn basic DC wiring.
They are way beyond what the OP said he was looking for.
crossthedog My question is which book about wiring a layout you would consider the EASIEST TO UNDERSTAND, like an idiot's guide. Not the most complete, not the one with the sweetest schematics, and not the one that goes into the most detail about outlying scenarios that I probably won't be pursuing... but the one you would consider most easy to grasp for someone electronically challenged but that still covers essentials for basic wiring of a DC layout.
-Kevin
Agreed, but that conversation was all over the map by the time I replied. I just think Mallery was one of the great thinkers in this hobby and his work does not get enough attention.
Sheldon
ATLANTIC CENTRALPaul Mallery's Electrical Handbook vol 1 & 2, enough theory so you can advance, without boring you silly. Covers the basics, and starts you on the advanced path if you are interested.
crossthedogMy question is which book about wiring a layout you would consider the EASIEST TO UNDERSTAND, like an idiot's guide. Not the most complete, not the one with the sweetest schematics, and not the one that goes into the most detail about outlying scenarios that I probably won't be pursuing... but the one you would consider most easy to grasp for someone electronically challenged but that still covers essentials for basic wiring of a DC layout.
Living the dream.
Your observations on writing clarity are well put. I find the "experts" really hard to follow most times as they to skip over the most basic questions a newbee might ask and therefore it's often more like going down an understanding deficit rat-hole trying to make their topic leaps.
Poor and incomplete manufacture product documention are equally to be called out and have cost me no end of grief. like for instance, not explaining what electronic LEDS on model railroad electronic boards mean. I thought a red LED light was bad in worldly principle, but apparently not to model railroad electronics. The basic question "what are lights telling me" seems to be umportant To manufactures!
manufacture documentation contradictions pop up every. Does nobody proof read?
Still what a hobby and the hobbyists and family manufactures that step up to give us the tools to make our dream worlds become a reality are to be commended. I thank them for it. MARKTO.
I'm still reading these responses, by the way. Thanks all.
Returning to model railroading after 40 years and taking unconscionable liberties with the SP&S, Northern Pacific and Great Northern roads in the '40s and '50s.
rrinker (...) If you forget to flip the switch, you will get a short when the loco crosses the gaps, sam as a DC reverse loop if you forget to flip the switch. (...)
If you forget to flip the switch, you will get a short when the loco crosses the gaps, sam as a DC reverse loop if you forget to flip the switch. (...)
Simon
snjroy Folks, I am referring to a situation where a DC layout is used in DCC, so without a DCC auto-reverser and where a return loop is managed through manual polarity switching. This was mentioned in the context of differences between DC wiring and DCC wiring. Simon
Folks, I am referring to a situation where a DC layout is used in DCC, so without a DCC auto-reverser and where a return loop is managed through manual polarity switching. This was mentioned in the context of differences between DC wiring and DCC wiring.
That works fine, too. You cna reverse a DCC layout using a toggle wired the same as a DC layout. The flipping of a toggle will probably cause an interruption in a soudn decoder though as it takes too long for the contacts to switch (relative to an automatic DCC reverser).
If you forget to flip the switch, you will get a short when the loco crosses the gaps, sam as a DC reverse loop if you forget to flip the switch.
But flipping the 'polarity' under a running DCC loco does absolutely nothing. The loco continues on its way. You take a whole layout, with a dozen runnign trains, and change the polarity of the wires right at the DCC booster and nothing will happen to those running trains. Forward in DCC is towards the front of the loco, the direction does not depend one whit on the signal on the rails (other than the contents of said signal is what instructs the loco to move).
The reason DCC tends to switch the reverse section itself rather than flip the main is because a) not all autoreverse can handle the current load of an entire layout and b) if the layout is sufficiently large, there won't be "a main" as it will be divided into multiple power districts which makes it impractical to switch all that simultaneously.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
are you still suggesting that flipping the mainline polarity while a DCC loco is in the reversing section can damage the loco?
with a DCC loco you could manually flip the reversing section polarity
greg - Philadelphia & Reading / Reading
snjroy a DCC engine will probably be damaged if you go through the gapped section, but forget to flip the switch to reverse the polarity. The engine will be "trapped" between sections of different polarities. I guess it would just short.
i don't see why a DCC engine would be damaged
yes, there will be short across the gaps. and the short causes the current to flow thru the metal frame of the loco instead of thru the decoder ... just like with DC.
as i said, a DCC auto-reverser relies on this short to reverse the track polarity of the reversing section
What I meant is if you have a return loop in DC mode, then convert to DCC (or run in DCC), a DCC engine will probably be damaged if you go through the gapped section, but forget to flip the switch to reverse the polarity. The engine will be "trapped" between sections of different polarities. I guess it would just short.
Lastspikemike ATLANTIC CENTRAL Lastspikemike For DC the convention for fluid motion through a reversing section results in fitting the polarity reversing device so as to reverse the polarity of the track outside the reversing section (generally referred to as the "main"). Polarity matches going in to the reversing section but polarity would not match going out unless it gets flipped. So, when the train is fully inside the reversing section (tail end metal wheels included) the polarity outside the reversing section is flipped to match polarity at the exit to the reversing section. The train inside the reversing section never experiences reversed polarity. But, it matters to every other locomotive outside the reversing section on the main polarity, unlike DCC. Outside the reversing section all other locomotives will reverse direction when the polarity is reversed on the main to match the DC reversing loop exit. Big difference in how you may operate. Actually if you design and wire your cab control system correctly, each separate throttle will have its own main and reverse loop switches, and they will only affect the blocks connected to that throttle, and have no effect on other throttles running other trains in other blocks. A much better approach........just one of many much better approaches to DC Sheldon I was referring to single powerpack layouts. My reversing sections use Atlas Controller switches so have dual cab control for any block or reversing section. Adding the third cab to this setup stumped me. So far.
ATLANTIC CENTRAL Lastspikemike For DC the convention for fluid motion through a reversing section results in fitting the polarity reversing device so as to reverse the polarity of the track outside the reversing section (generally referred to as the "main"). Polarity matches going in to the reversing section but polarity would not match going out unless it gets flipped. So, when the train is fully inside the reversing section (tail end metal wheels included) the polarity outside the reversing section is flipped to match polarity at the exit to the reversing section. The train inside the reversing section never experiences reversed polarity. But, it matters to every other locomotive outside the reversing section on the main polarity, unlike DCC. Outside the reversing section all other locomotives will reverse direction when the polarity is reversed on the main to match the DC reversing loop exit. Big difference in how you may operate. Actually if you design and wire your cab control system correctly, each separate throttle will have its own main and reverse loop switches, and they will only affect the blocks connected to that throttle, and have no effect on other throttles running other trains in other blocks. A much better approach........just one of many much better approaches to DC Sheldon
Lastspikemike For DC the convention for fluid motion through a reversing section results in fitting the polarity reversing device so as to reverse the polarity of the track outside the reversing section (generally referred to as the "main"). Polarity matches going in to the reversing section but polarity would not match going out unless it gets flipped. So, when the train is fully inside the reversing section (tail end metal wheels included) the polarity outside the reversing section is flipped to match polarity at the exit to the reversing section. The train inside the reversing section never experiences reversed polarity. But, it matters to every other locomotive outside the reversing section on the main polarity, unlike DCC. Outside the reversing section all other locomotives will reverse direction when the polarity is reversed on the main to match the DC reversing loop exit. Big difference in how you may operate.
For DC the convention for fluid motion through a reversing section results in fitting the polarity reversing device so as to reverse the polarity of the track outside the reversing section (generally referred to as the "main"). Polarity matches going in to the reversing section but polarity would not match going out unless it gets flipped. So, when the train is fully inside the reversing section (tail end metal wheels included) the polarity outside the reversing section is flipped to match polarity at the exit to the reversing section. The train inside the reversing section never experiences reversed polarity. But, it matters to every other locomotive outside the reversing section on the main polarity, unlike DCC. Outside the reversing section all other locomotives will reverse direction when the polarity is reversed on the main to match the DC reversing loop exit. Big difference in how you may operate.
Actually if you design and wire your cab control system correctly, each separate throttle will have its own main and reverse loop switches, and they will only affect the blocks connected to that throttle, and have no effect on other throttles running other trains in other blocks.
A much better approach........just one of many much better approaches to DC
I was referring to single powerpack layouts.
My reversing sections use Atlas Controller switches so have dual cab control for any block or reversing section. Adding the third cab to this setup stumped me. So far.
Well, you can't do it with that stuff from Atlas, but when you want to know, look me up.
A properly set up can control system can have as many throttles as you want and be much more "user friendly".
My mainline will have six throttles available, other areas of the layout will be able to connect to them, as well as having additional separate throttles.
My throttles are wireless radio, but good DC control schemes will work with any kind of throttle.
Here is the thing about DC - except some of basic rules, follow some proven conventions, decide what features you want, and a number of different possible user friendly systems can be put together.
Some require more wiring and hardware, some are pretty simple, but most of the good ones don't use block toggle switches in the traditional sense.
If you have access to the MR archives, look up a series of articles by Ed Ravenscroft starting in Feb 1974 about his MZL control. It is just one of many great DC systems over the years.
If you do look it up, don't get too caught up in the exact wiring, he used a very old detection circuit and built his own throttles. But his operational premise is genius.
While a lot of what you have posted on here is true and works, most of it has limitations that are a dead end for expansion or easy use beyond what you have done.
And while a common rail or common buss system was popular decades ago, the use of modern throttles will go better with complete isolation of each throttle.
My ten throttles each have their own power supply and from power supply to locomotive the power supplies are never connected to each other as the 10 trains move about the layout.
When I was a young man I was, among other things, an electrical control systems designer, back in the days of relays, before computers. Systems that controlled pumping stations, auto assembly lines, steel mills, process machinery of every sort.
When Programable Logic Controllers came along, I learned them and I learned how to re-write relay logic into PLC programing.
Today I would rather use a relay than a computer to control a model train.....
ATLANTIC CENTRALActually if you design and wire your cab control system correctly, each separate throttle will have its own main and reverse loop switches, and they will only affect the blocks connected to that throttle, and have no effect on other throttles running other trains in other blocks.
This is my approach to the reverse loop in DC.
On my layout there will only be one reversing section, except for the two turntables.
This section of track that will need to be reversed will only be controlled by one throttle, and trains will alternate Northbound and Southbound through this section.
To make the reversing section seemless, there will be two industries in this section, one with a trailing point turnout Northbound, and one with a trailing point Southbound. All trains going through this section will need to switch a car at one of these industries.
So, as you go Southbound, the train stops, and reverse direction to either pick up or set out a car at one of the industries. As you go Northbound, same thing.
The FIRST directional change for switching will be done with the polarity reverser for that electrical block. All other direction changes will be done with the power pack. Then when you leave the block, polarity will be correct, and correct for the next train entering the block.
Very simple, no electrical tricks to remember.
I believe I read about this operating scheme in an article from a 1950s Model Railroader.
snjroyI'm not an expert, but reversing the polarity on a DCC layout for a return loop operation sounds risky to me, especially if there are other trains operating elsewhere on the layout.
the track voltage on each rail in DCC is constantly alternating. a rectifier in the decoder makes this DC just as the rectifier in an DC throttle rectifies the AC power from the wall.
motor direction is not determined by track polarity. the DCC command station sends a DCC command over the track telling the decoder which direction the loco should move. the decoder controls the motor voltage using an h-bridge.
just as in DC, each rail of a DCC reversing section must be gapped to prevent a short and the connections between the reversing and mainline rails may need to be swapped even though they are alternating because they are alternating in opposite directions.
but unlike DC, a DCC auto reverser can very quickly (within a msec) detect a short and reverse the polarity of just the reversing loop when a loco bridges the gaps of a reversing section that have opposite polarity.
capacitance in the decoder prevents it from reseting due to the brief loss of power due to the short. the decoder will detect and discards any DCC command corrupted due to both the loss of power and the reversing of polarity. reversing the track polarity only affects locos in the reversing section.
digtalal bits are communicated over the track based on the time between polarity reversals -- hence why DCC track voltage is constantly alternating and why reversing track polarity corrupts any DCC command when the polarity is reversed.
SeeYou190 rrinker The easiest way to wire a dogbone is to make the two end loops reversing sections, then you can have any number of crossovers without creating a reverse loop situation. Randy, I have thought this myself. Am I understanding this right... On a dogbone layout with a narrow center section with crossovers, wire the narrow section directly to the DCC system, and put auto-reversers on both end loops. Is that correct? -Kevin
rrinker The easiest way to wire a dogbone is to make the two end loops reversing sections, then you can have any number of crossovers without creating a reverse loop situation.
Randy, I have thought this myself. Am I understanding this right...
On a dogbone layout with a narrow center section with crossovers, wire the narrow section directly to the DCC system, and put auto-reversers on both end loops.
Is that correct?
Yes, and there are good reasons to wire a DC layout of that configuration in a similar way.
Again assuming the center of the dogbone is intended to simulate a double track mainline with crossovers.
snjroyI'm not an expert, but reversing the polarity on a DCC layout for a return loop operation sounds risky to me, especially if there are other trains operating elsewhere on the layout. And I would not want to see a DCC locomotive accidently go through a section with an inverted polarity.
rrinkerThe easiest way to wire a dogbone is to make the two end loops reversing sections, then you can have any number of crossovers without creating a reverse loop situation.
I'm not an expert, but reversing the polarity on a DCC layout for a return loop operation sounds risky to me, especially if there are other trains operating elsewhere on the layout. And I would not want to see a DCC locomotive accidently go through a section with an inverted polarity. Something tells me that the Poof effect will appear!
If you build a dogbone layout, and have any crossovers int he narrow part where the two tracks are close together, you have reverse loops. The easiest way to wire a dogbone is to make the two end loops reversing sections, then you can have any number of crossovers without creating a reverse loop situation.
crossthedogFinally, from the comments here I can see I need to settle my track plan. I thought I had it down but then started lying awake at night
I have been fleshing out the details of my next layout in my head for about seven years when I decided that the spare bedroom layout was not my final layout.
I still have not fully settled on a plan.
Thanks for the feedback, everyone. Somewhere in my online forum reading (all a confusion in my head now) I think I made a 'note to self' not to use common rail, whatever it was. I think I remember learning that if I just ran bus wires under the basic track plan with feeders at key points I could then use a DPDT to switch between DC and DCC, running the layout one way or the other.
I foresee my normal DC operations being running a longer passenger or freight on my loop while doing some switching on isolated spurs, so maybe two locos at a time, max, because it'll just be me. I don't have modeler friends (present virtual comp'ny excepted) and don't foresee operating sessions happening in my dank garage. So I don't think I need many blocks or many throttles/cabs. Even when I run DCC, which I want to do sooner than later, it will still only be one or two engines -- one on the continuous loop and one in the yard or spotting cars outside of town.
Also, I'm avoiding reverse loops. I have enough room for a tight dogbone.
So I think I might get several of the books mentioned. It doesn't surprise me that the writers of yore were better at communicating. But I also hear your cautions that much of their stuff is obsolete, and I would have expected that.
Finally, from the comments here I can see I need to settle my track plan. I thought I had it down but then started lying awake at night, playing with the idea of two separate, not-connected plans within one layout, DC on an outside ovalish loop with a small yard outside the loop, and DCC starting on the inside and rising out of (and crossing over) the DC loop into more creative switching scenarios. That way I would have zero chance of frying any engines, and I could wire each set of tracks in the way that was best for each. Not sure, though. I don't like any of the designs I came up with for getting up and out of the interior without it looking like a ramp.
Still cogitating...
-mdf
All good suggestions above! If you run into problems just post them here, tons of free information is available on this Forum. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Even with DC there are lots of good reasons not to use common rail or common return wiring.
I have 10 DC wireless throttles, each with its own 4 amp power supply. When they are connected to a section of track, they are completely isolated from the other power supplies.
This provides a long list of benefits including being the basis of my free Automatc Train Control. If you run a red signal, you train just stops, it does not get picked by some other throttle in the next block, it does not create a short, it just stops.
But then again I don't have any block toggles or rotary switches either, that is done another way.......
Paul Mallery's Electrical Handbook vol 1 & 2, enough theory so you can advance, without boring you silly. Covers the basics, and starts you on the advanced path if you are interested.
Mallery had his own ideas, some never tried, about possible advanced versions of DC. Some of which I did use and perfect in my Advanced Cab Control system.
Ed Ravenscroft was also a forward thinker, just reading his MZL Control series in MR is full of DC ideas that can be applied separately without using his whole system.
His system, some of Mallery's ideas, and my experiences at the Severna Park Model Railroad Club set the basis for my Advanced Cab Control - DC without block toggles......... but without the limitations of Wescott's progressive cab control.
dknelsonBUT I do believe it is all tied to the "common rail" version of DC wiring which in turn is also the system that the Atlas components are tied to.
Great point.
If your plan is to build a DC layout and then convert it to DCC, which reading the original post might be the plan, common rail should be avoided.
Listen to the DCC guys (not me) if this is the plan.
The Atlas book (books?) is/are easy to understand and is/are very clearly illustrated BUT I do believe it is all tied to the "common rail" version of DC wiring which in turn is also the system that the Atlas components are tied to. That is a perfectly good system but it is my understanding that some have found it easier to convert the non- common rail wiring layout to DCC when the time comes. Fewer new gaps needed for power districts and that sort of thing. In any event the Atlas books pretty much ignore DC wiring which is not common rail. And if you use Atlas components, that's fine. You don't have to understand so much, you just connect stuff the way the drawings tell you.
The Linn Westcott book still has things of value for those wanting DC wiring but it dates from an era when guys were building their own power packs, so it goes into a lot of electrical and DC theory, and LHW was also an early adopter and promotor of technology such as progressive cab control which never really took off. The consequence is that large swaths of the book are outdated or irrelevant. Who today for example needs to know how to hook up an electric motor to the rheostat or potentiometer on their throttle so they could get momentum?
I happen to think that Andy Sperandeo's Kalmbach book on wiring is more clear and easier to follow than Westcott's, and being more recent is able to eliminate the most outdated stuff. Ironically the least useful parts are those that deal with DCC because it was issued very early in the DCC era. For those wiring to DC standards, and who want to know the pros and cons of Atlas's common rail system, I'd look for Sperandeo. For the most part Sperandeo is careful to provide content for those using Atlas components and common rail rather than DPDT or rotary switches and non-common rail for example.
I was not that impressed with Larry Puckett's book on wiring, which superceded Sperandeo's. You could sense his impatience with the whole idea of DC wiring, for perhaps understandable reasons. He knows his stuff of course so it is far from worthless and I imagine many layouts were wired nicely using only Puckett's book. But also I never found Puckett to be a very clear writer in his monthly column in MR, nor in this book (nor do I find Mark Juett to be a very clear writer about wiring in the NMRA magazine). And perhaps as a consequence, I think both Westcott and Sperandeo as book authors were better able to communicate with the Kalmbach illustrators who had to provide drawings to match the text. That is an important factor in a good wiring book: can the illustrators understand the text well enough to provide a truly helpful drawing?
Dave Nelson
I think it really depends whether you are in DC or DCC. Not offense to the others, but the DC books contain a lot of information that is not really relevant to DCC. In fact, there are things in there that should not be done for a DCC layout... I bought the Kalmbach book "Basic DCC wiring for your Model Railroad", and I think it does the job in terms of covering the basics. If you want to learn basics about electricity, then I would suggest you read a more generic source of information that covers the basics, like what voltage, amps, resistance, watts, alternative current, and direct current mean. There are really good sites out there that explain it.
Survey says?.... The Atlas wiring book. Thanks fellas. I'm on it. I particularly like the idea of seeing the path of the electricity through the switches; I learn visually.
Still open to differing viewpoints, but I think I know my first move now.
Now anybody know how to edit or create a signature? I thought I had supplied one but this Trains.com world is so confusing.
UPDATE 3/18: I wrote the above yesterday, thought I'd posted it but hadn't. Clicked send this morning and then saw several new responses, which I appreciate and will consider.
-Matt
Atlas my list their products but other products can be substituted.