For $75 to $150 you can run a DC and a DCC loco on your layout at the same time with the same phone or WiFi throttle... Sumner
That's pretty cool! Maybe there's a use for block-controlled layouts after all?! While it's possible to run both DC and DCC sections of any layout with large-scale DCC decoders powering the DC track (with sound), it cannot easily switch any block from DC to DCC or back via the throttle. Is any block also selectable as a programming track too? If so, is there a way to prohibit that choice (or at least that choice from a throttle) for any blocks? Thanks for the demo!
Yes any block can be a program track. You can see it around the 3:44 mark. You have to select it from a list so kind of hard to do it accidentally. I haven't tried it but think if it becomes a program track it would act like one and you couldn't drive a loco at that point. So nothing would move and nothing would be programmed either unless you went further. Also to program accidentally you would have to connect something like DecoderPro to program so don't see a problem of switching to it accidentally and anything getting programmed. On that screen for a moment you can also see where you can go and program a single CV at a time if you are on a program track or now the main also. You can't read the CV change at this time but might be an option later. Since you are only changing a single CV I don't see that being a big thing as after you change you would probably run the loco right away and see if the change was in the right direction. I don't see myself using it as I'll do all my programming on my small oval where I can do that now. I got parts the other day and am starting to build a new DCC-EX command station with four $5 motorshields that will give me 8 track outputs (8 Blocks) that I can change with the throttle at any time to DCC or DC. That will let me run a ton of DC locos I'll probably never have the time to convert to DC in any of the blocks or the whole layout switched to DC. Thanks for the input, Sumner
So any given track output can be either program-only or run-only, but not both? So I guess you designate your programming track as run-only, drive your loco onto it, then re-designate that track as program-only, and program. Then re-designate that track again as run-only, and run it back out on the mainline. I like DCC-EX's flexibility, but mostly for DC/DCC. I'm not sure I like the ability to, from the throttle, accidentally re-config the wrong track for programming and proceed to confuse the heck out of the wrong locomotive(s) on the wrong track! It would be nice to have an option to prevent certain districts from being accidentally/mistakenly configured as programming track(s) via the throttle. Transponding gives you the benefits of programming feedback, without the risks to other locomotives on conventional programming tracks. NCE's little Auto-Switch device can guard against accidentally programming elsewhere than the programming track, but for DCC-EX, you would have to purchase one for each DCC mainline district output. Lots of people use it that way (with one non-programming DCC district). Or, with conventional districts using separate boosters, you deploy the auto-switch upstream from the mainline district boosters. Or DCC-EX could do it in software... "It's only software; how hard can it be?"
You have the ability from the throttle to change a block in a matter of seconds to any of the following: Main (DCC), Program Track (DCC), DC, DC polarity reversed (if the loco is going in reverse while the throttle is in fwd -- a problem with about any DC throttle) and a couple other options that I haven't studied up on. It does take more than a couple key strokes so you have some time to think about what you are doing . If you are DCC only most would probably use an electrical isolated siding as the programming track. Have it selected as the Main....drive on....change it to a Prog. track....use your programmer ...change the track back to Main and drive off and anywhere on the layout. If you want to run DC and DCC locos then if it was me the blocks would be much larger than just a siding. Then one would have a lot more options on where to run either the DC of DCC loco. Then if I wanted to switch blocks I'd have some sidings that I could cut the power to and use them as storage tracks. The best option would be to spend $50 for the second board that plugs into the CSB1 command station that gives you two more track outputs for 2 more districts. Then using the throttle you could drive between districts using the throttle to change between DC and DCC with the two locos (or consists) and use the 3rd and the 4th as blocks that you change on the fly to move the locos between blocks. DC from block 1 to block 2...change block 1 to DCC and the other loco can drive onto it and so forth. To do this one would probably want to be able to do it quickly with the throttle. Yes if one wants the flexibility, I do, then they are going to have to get some practice on using the throttle and also laying the blocks out. Most DCC locos can run onto a DC block without harm and I thing I've had a DC loco on my layout before with the DCC on with out harm but that probably isn't true for all situation. It would be hard to actually program the wrong loco by accident, not saying it couldn't happen. If you use the program on the main function you have to supply the loco's DCC address to do it so I don't think you can reprogram any locos that are on other addresses. Also one doesn't need to use the ability of changing blocks between DC and DCC. There is nothing on the throttle that will do that with only one or two pushes of the button unless the throttle lets you assign a series of tasks to a button. For someone that is all DCC or DC put it in one mode and never change it. I probably have 20-30 locos I'll never convert so for me this is big. Also a lot of DC only modelers want a wireless handheld throttle and I think there were some in the past but the supply now is either none or very limited. Now for $150 they can have that via the command station and an Android phone or they can spend more and buy a commercial throttle like TCS's UWT-50 OR -100 to use with the command station and have between 2-4 operators all with wireless throttles depend on if they have 2 or 4 blocks. Sumner
The ability to reverse polarity persistently on a DC track may have to do with the ability to run a DCC loco that can also run on DC, from a DCC track to a DC track cleanly. Does DCC++ remember that track polarity reversal through a power cycle (e.g. for the next session, days later)? I can also see where DCC-EX would really be the cat's meow for folks with large stables of DC locomotives they want to run on their blocked-DC layout, and never even touch DCC. Can DCC-EX do pulse-stretching within the DCC waveform to run both DC and DCC locos together on the same track/power district? I'm not in the same position you are, with a large stable of DC locos I need to be able to run (and where DCC pulse-stretching wouldn't work well with their favorite old locomotive), so the mixed DC/DCC capabilities are just not important to me, but there are lots of model railroaders for whom it could be a god-send, and perhaps even a path to dip their toes into DCC. And if they get hooked on DCC, and want some of the higher-end features that some commercial DCC systems offer (e.g. RailCom, LCC*, etc.) then they still have a place to grow in. We really don't have just one DCC market, we have a few different ones. *I have heard of a few SW projects running CAN-bus LCC nodes on Arduinos, but that may be too much processing to also run DCC on the same Arduino. Besides, you generally need multiple LCC nodes, but only one DCC command node. If the projects are viable, LCC is a great way to connect occupancy detectors, signals, switch controls, etc., in a distributed, networked, status & control system.
BigJake YES that is my understanding of Sumner's excellent VDO demonstration. I have a standard dc 12 block layout using dual input Atlas 'selectors' (ie: A input is 'up" B is 'down') PLUS standard dc polarity reverse-loop "Controller' that is "pulsed" (by means of a momentary turnout button) to avoid mistakes thereby double-checking polarity prior to dc loco entering a new direction track. Of course, if running in dcc mode the second Atlas "B" input normally wouldn't be used at all UNLESS I used the only "non-pulsed" "B input" reverse-loop powered TURNTABLE track as a programming platform? In strict "dcc mode" the only thing am of unsure of is -> would "common-rail" be a problem between "main" & "program" track or is total isolation a necessity? Then again the fact that you'd only be doing ONE THING AT A TIME (ie: disconnect main selector 'A' & "B" while programming) should make it 'ok'? Will test & let know (if USPO mail ever arrives!) (ps: noticed with both dc power-packs ON I can put both A & B "Atlas Controller" direction switches in "neutral" and "Reverse-Loop" powered turntable for "programming" still WORKS)
I'll try and answer some of these questions to the best of my ability but for anyone interested in this I'd for sure go to the documentation on the DCC-EX site. There are lots of ways that you can use TrackManager from the software and the hardware side. They have more documentation for different aspects of using DCC-EX than I've seen from anyone else. At the following link you can find a menu on the right that takes one to info on a lot of aspects of TrackManager .... https://dcc-ex.com/trackmanager/index.html#gsc.tab=0 The main reason for the DC reverse polarity I believe is to make throttle commands consistent with respect to direction. On my older DC throttle if I set a loco on the track and give it throttle it will take off in one direction. I change the direction switch and it goes the other direction. The direction switch is not a forward/reverse switch like what you see on a DCC throttle. Leave the switch where it is and pick the loco up and turn it around on the track and give it throttle and it goes the opposite way. With a DCC throttle we have fwd and reverse on the throttle. If you use TrackManager to switch the block to DC then run the loco you might find it going in reverse when the throttle is set to forward due to the polarity of the track. Use the throttle to reverse the track polarity in DC mode and now the direction the loco goes will match the throttle. On my DC throttle HandCab DC which has a reverser handle one can run into the same situation depending on which direction the loco is facing when put on the track. I have a DPDT switch on the control stalk that you flip and now the reverser handle corresponds to the direction the loco goes when changed from fwd to reverse. If you have changed it during a session probably not but I don't know that for sure. When you install the software or later at any time you can set the default settings for the blocks to any of the choices on startup. Then change them while operating. DCC-EX doesn't use the zero stretching on purpose for a couple reasons. One is for the reason you stated, that it can be harmful to some older locos. The other is that some engines can sit there humming at zero throttle. With their DC wave form that doesn't happen, the loco is dead quiet until you give it throttle. When the command station is send DC to a bock it is PWM DC. Some locos work on different frequencies better than other frequencies. You have the option of 4 different frequencies that can be changed by the throttle at any time the loco is stopped. One can experiment with a loco and find which works best for that loco and change to it with the throttle when that loco is selected. I've run a few DC locos now with the default frequency and they run great so haven't tried the options. I haven't tried any of my DCC locos on DC but do know that is an option with some decoders. Not sure how it works with respect to controlling the loco, probably sees the polarity and track voltage and bypasses the decoder doing that work but not sure. I can see where one might be able to drive onto a DC section but then the loco wouldn't be controlled by the throttle anymore for that block but would be controlled by whatever is controlling the DC in that block. In DCC we set the throttle to the loco's DCC address when using the DC mode it is somewhat different. We assign a number, any number, to the block. In the video I used the number 604 as that was the engine number but I could of used 1111. Using your throttle you select the number that you assigned to the block instead of a number for a an engine. They can be the same if you want or in the case of driving a DCC loco onto a block you could assign that loco's number to the block and then when it went onto the block the loco would still be under the throttles command. Like with any DC setup we have to remember that any other DC locos on that block are all going to be controlled by the throttle at the same time with the same voltage/polarity. If I was going to drive a DCC loco onto a DC block I'd just change the block to DCC before doing it and have my DC loco/loco's parked in un-powered sidings. DCC-EX can also now run on more powerful platforms with more speed, memory and outputs than an Arduino has if one wants. The auto-installer will put the software on the command station for the platform you select. I would not recommend this for someone who isn't really into working with something more than a simple DIY project like the DIY version of DCC-EX. I won't pursue this unless somewhere down the road I find the standard base station not capable off my needs but don't really see that happening even if I start using automation for some aspects of the layout. Of note the CSB1 ready to run command station is ESP32 based and not Arduino based and you can build a ESP32 based system and load the software via their auto-installer. As it is now with my Arduino based command station I can expanded using EX‑IOExpander as an additional micro-controller utilized to expand the I/O port capability of an EX-CommandStation and connecting via I2C. Users out there now are building very large layouts with it and controlling lots of different items on the layout. Sumner
The blocks have to be totally isolated with cuts or insulated rail joiner for any blocks you have. If one uses 'common rail' you already have a cut in one rail for your blocks. You only need to cut the other rail adjacent to that cut and you will be fine. If for some reason you still want the option of 'common rail' one could wire across that gap with a switch in the wire to connect the gap when you wanted 'common rail'. Sumner
But can I assume on an only one polarity dcc track that my manually switched reversing loop tracks will still work normally? Upon entry ensure that loop polarity agrees and then, upon exit, mainline polarity (different direction) is switched to conform as well (as long as no other locos are in same block)?
You can do it the same way as DC, but you don't have to with DCC. With DCC, forward/reverse is always WRT to the loco. With DC, forward/reverse is always WRT to the track polarity.
Yes you're DPDT Switch should still work the same for the reversing loop if the block it is in is DC or DCC and you need it for both. DCC doesn't have polarity like DC but you have to still treat the track the same. It is in one phase (don't ask me what that is) on one track rail and a different phase on the other track rail, kind of like polarity but not polarity. It would act the same as DC coming out of a reversing loop if the phases didn't match the command station should act like a short and shut down. So you do need the DPDT switch to reverse phases while the loco is in the reversing loop. As Andy mentioned a DCC loco will still go forward without stopping when you do this. With your DC loco do you stop it before throwing the switch and then throw the direction switch on the throttle. If not I'd think when you threw the switch the loco would reverse direction. You could use an auto reverser it it was DCC all the time like Tam Valley's but theirs will not work for DC also. Anyone aware of one that works for DC and DCC also? Your block wiring should also be in phase as a loco moves from one block to another with DCC. Track wires on both sides of an isolation gap should be connected to the rails on the same side. Sumner
Sumner, all phase means with DCC is that at any given point in time, one rail is at 12V while the other is at ground, a track in the opposite phase will have the opposite polarity. If loco crosses the gap into a block in the opposite phase, there is an immediate short. I believe most DCC autoreversers flip the phase on the block the loco is currently occupying (probably for convenience if a booster is integrated) allowing the train to continue past the gap. Since the decoder is fed power via a rectifier, the decoder doesn't care about polarity and at most you might get one garbled DCC message. With DC you can't flip the polarity on the block the loco is in, as it would immediately reverse direction, so you have to flip the polarity on the block the loco is about to enter, which works fine as long as that block is unoccupied. DCC also works when flipping the phase of the next block rather than the current. I managed to get both DC and DCC auto-reversing working by doing the latter in my own command station code, I expect DCC-EX will do the same at some point. One added complexity for DC autoreversing, PWM signals on both sides of the gap also need to be in phase (rails on both sides of the gap at same polarity), which usually means figuring out how synchronize the PWM clocks if more than one PWM timer is being used for different blocks.
Thanks, I didn't catch the .... .... switching the mainline polarity. At this point Michael I think it would be good if you posted a basic track plan of the layout showing the blocks that you would be using. Also how you want to use them. Are you planning on only running DC loco's using the DC option with DCC-EX or only DCC loco's or a combination? Sumner
One aspect of running DC loco's with PWM is how the motor "reacts" to the PWM frequency. Older motors may require a change to the default PWM frequency. Fortunately, EX-Command Station supports 4 PWM frequencies to "help match" the motor. The default is 131Hz with options for 490Hz, 3.4kHz and 62.5kHz. An example of the 2010 vintage Atlas VO1000 at the default 131Hz PWM freq. Once the block or track has been set to DC mode with an address, then acquired by your throttle and with loco is at 0 speed, the PWM frequency can be set by throttle via Functions F29, F30 or F31 respectively. Or, The PWM frequency can be set by the EXRAIL command; SETFREQ( track, frequency ) Perhaps the figure below helps clarify.
My last SCARM layout is posted here but is NOT CORRECT am amazed at how many changes been made (thus no real 'progress'?) If one takes out the "Industrial yards" and two "pax station" sidings and insert an AFX 4 lane slot track then it is more or less - still a mess - what you see attached: I have two other dcc ready 'Mainline" locos I plan to convert to dcc (plus 3 other unused dc 'junk') so if "mixed running" then only temporarily will experiment and see how goes. But I do see how reversing a dcc mainline siding coming out of a reverse-loop would only prove a management problem for other active locos online. As an aside I do have PWModulators inline with current TYCO 18v dc setup but look forward to dcc control only and not needing them anymore! AM STILL WAITING ON MAIL from China but plenty "tado" in the meantime! Thanks to All! (ps: USPO is terrible! An unrelated order is feared LOST somebody must be "scanning" but North Carolina? I live just outside Atlanta did all the "immigrants" not show up and/or fired!) Spoiler: US Mail! Shipment history USPS: Sat, Feb 15 12:00am In Transit to Next Facility, Arriving Late Fri, Feb 14 12:00am In Transit to Next Facility, Arriving Late Thu, Feb 13 12:00am In Transit to Next Facility, Arriving Late Wed, Feb 12 12:00am In Transit to Next Facility, Arriving Late Tue, Feb 11 2:23am Arrived at USPS Regional Destination Facility ATLANTA GA DISTRIBUTION CENTER, 30267 Thu, Feb 6 12:00am In Transit to Next Facility, Arriving Late Wed, Feb 5 12:00am In Transit to Next Facility, Arriving Late Tue, Feb 4 12:00am In Transit to Next Facility, Arriving Late Mon, Feb 3 12:00am In Transit to Next Facility Sun, Feb 2 7:17am Arrived at USPS Facility GASTONIA, NC 28054 Sun, Feb 2 2:41am In Transit to Next Facility Sat, Feb 1 11:03am In Transit, Arriving On Time Fri, Jan 31 6:45pm In Transit, Arriving On Time *sigh* DCC-EX news (Trump strikes)!
If your plan is to be primarily DCC and you would confine DC locos to not needing to run around a reversing loop I'd wire the whole layout like you would any DCC layout and put auto-reversers in the reversing sections. They aren't that expensive and DCC-EX can do it but I believe that using up that option uses up one of the track outputs you might want to use for a block that could switch between DCC & DC. Or you could use a DPDT switch in the reversing sections and throw the switch while the train is in the reversing section (not reversing the mainline) you would be fine. You could use the option to change a block to DC with the command station. Just don't run the DC locos all the way around the reversing loop unless you have a way to deal with that. I have a couple reversing sections on my layout but the plan is I have so many other places to run a DC loco I'll restrict them from the reversing sections. Sumner
I believe your understanding of how DCC auto-reversing typically works is misinformed. There is no knowledge required of which block(s) a loco (or any metal wheel) is entering or leaving. An auto-reversing section, or zone, assuming metal wheels are used on railcars, is usually longer than the length of the longest train to be run through it (assuming metal wheels on railcars). When there is a track short in that zone, the polarity of the zone power is reversed. If that does not remove the short quickly, then the booster will shut down to protect itself. Note that the length of the auto-reversing section must be long enough to hold the longest train to pass through it (assuming metal wheels are used on railcars.) This method works no matter whether the short happens upon locomotive/railcar entry to and/or exit from the AR section. Therefore, it is not necessary to "un-reverse" the section polarity after a set time. It will happen only when it needs to happen. The whole notion of knowing where a train is, was, or will be, has nothing to do with it. See a short, flip polarity. If that doesn't work, then shut down.
You may be right, but I see this from a programmer's system perspective, rather than as a DCC expert (I own all of two DCC locos, and a ton of DC). I have never owned a "factory" DCC auto-reverser, so I can only guess what they do. All my testing is done with a loco and a few cars, some with metal wheels, some not. The test blocks are longer than the longest train. When a short occurs, it will be be detected in two places, the current block and the one the train is entering. With DCC I can flip the polarity/phase on either one, it doesn't matter. With DC is certainly does matter, so I have to flip the polarity and mode (DC or DCC) of the correct block (i.e. the next one). To make it work I keep track of the order in which shorts and current draw occur for each train, and I flip both DC and DCC blocks based on that ordering. From that information (and the direction/speed set for each DC or DCC cab) I can infer the direction of movement of each train. If there are better ways, I'd be happy to hear them, y'all might get a new and possibly useful DC/DCC command station written in a modern language (MicroPython running on Pi Picos and compatibles) that is easier to fiddle with to do whatever you want.
Interesting... DC auto-reverse. Most small, brushed-DC-motor driver ICs monitor current by measuring only the return current, not the supplied current. (It's easier=cheaper that way.) The supply side would have an external (likely PTC) over-current protector feeding the motor driver IC. Unfortunately, when that trips, you don't have a reliable way of knowing that in SW. In the case of a track short between two adjacent blocks of track, driven with opposite polarity by two separate motor drivers, the current is sourced (but not sensed) by one block's driver, and sunk (and sensed) only by the other block's driver. Therefore, when monitoring DC* track current, you may not sense two shorts, only one, and there's no way to determine which adjacent blocks' current it is. *DCC has rapidly alternating polarity, so both tracks' drivers will see the over-current indication from the motor driver.
