That was pretty impressive! I assume, given the separate DCC & DC tracks, the motor driver board was driving true analog DC on the DC track, and a separate motor driver output was driving DCC on the the DCC track. If a loco or even a wheelset bridges the gap between DCC and DC tracks, both tracks are likely to shut down. Many DCC systems use NMRA-standard DCC pulse-stretching in the DCC waveform to create a DC component to run analog locomotives (all at same speed) on DCC tracks, alongside, or even consisted with, DCC engines. This allows either type of locomotive to go anywhere on the layout. Does DCC-EX also support pulse-stretched DC on the DCC track bus?
I had better not try to explain it as I'll probably get it wrong. Here is right from the horses mouth as they might say..... Welcome to DCC-EX TrackManager I might have to try this out on my test track. If I can get it figured out I could later use this on my main layout possible to fairly easily run a lot of the DC locos I have that haven't been converted to DCC yet. The really nice and very impressive part is you can use the same phone throttle to run DC and DCC trains at the same time. I don't think there is another phone throttle app that can be used for DC locos. And the one available is EngineDriver that is really powerful in its on right as demonstrated in the video. Peter Akers and Steve Todd who are responsible for EngineDriver are two of the main players in DCC-EX's development along of course with others such as FlightRisk on here who is hugely responsible for DCC-EX. Sumner
Lots of variables.......but for me, I added up the costs of the control system for my current layout , and for my previous layout and due to the amount of wire, and switches and dials and associated hardware for DC vs a $400 DCC system and a buss wire and some feeder wire, DCC cost me less than half, and we're talking an 8 X 12 DC vs 42 X 16 DCC. But as size gets smaller the difference gets smaller also, and for small DC layouts (HCD and smaller) wiring can be pretty basic either way and a DC power supply is about half what a starter DCC system is. For a smaller layout, it really comes down to whether or not you want the features you gain with DCC. If you own a few hundred locos like Doug, DCC can definitely be a serious cost, but on my layout (16 X 42) I only have 10 locos actually sitting on the layout. I have a hidden staging yard and there I have an all the trains that will appear on the layout........those will pass thru and drop off and pick up cars. There are 6 tracks/trains, so there are additional locos there......because there's a 2% grade most of the trains have 3 locos (to pull 40 cars) but that's still less than 30 locos total. And if you are just starting out, it's getting harder and harder to find DC only locos, so the cost in locos is virtually the same. I have the advantage that our NTRAK club has remained DC, so I can run old locos there and keep the DCC stuff at home. Although the club is considered DC, we have the option of bringing in our own DCC systems and plugging it in to one of the 4 lines........some days 3 of the 4 lines will be running DCC. I personally use MRC systems because that's what several other club members use, and I found it very easy to use. I have 2 systems, a Prodigy Advance that I use at the club, and a Prodigy Elite at home. The Advance let's me use the MRC WiFi, which I find very handy at the club because it's wireless (most members are tied to a tether) and also because I can have 2 throttles showing on my phone, so I can run 2 trains without having to switch back and forth.......and I can still have the tethered throttle plugged in as well. For some reason the Elite unit won't accept the WiFi module, so at home I use a tethered throttle for mainline trains, and a wireless throttle for switching. I also don't run all day at home, so the wireless throttle isn't a disadvanteage........it only runs about 3 hours on a charge/set of batteries, while the tablet/phones I use will run all day.
Gents, thank you for your very clear and thoughtful answers. This is exactly what someone who is new needs to understand so they can make an informed decision.
My new layout is DCC but has a DPDT switch so I can run DC locomotives when I want to. My old DC layout was a nightmare of a 'rats nest' of wiring underneath to run DC ! With DCC I have 4 'power districts' of two wire buss lines. I never put in the PM42 Each power district runs about 10 feet of double track mains...both front and rear on the layout. I have drop feeds every 3 pieces of Unitrack or roughly every length of one flex track. These same power districts works great on DC when I run DC locomotives ! BartowRick had sent me an old Atlas Commander to try out DCC years ago. I was hooked immediately !! I have since upgraded my DCC system and of course my BIGGER layout and have never looked back. I love the DPDT switch and the ability to still run DC locomotives though. Just don't run the DC locomotives through the double crossovers...yikes THE BEST OF BOTH WORLDS !!! .
Thanks for the info and link for the information! DCC-EX analog (for DC locos) MUST be wired to separate tracks, segregated exclusively for analog/DC operation, as shown in the video, and both rails have to to be gapped between DCC and analog/DC zones. The primary advantage of this implementation is that by adding additional motor drivers, one can have multiple, independent DC zones exclusively for DC locomotives (e.g. block-DC operation). I don't know how many motor driver boards DCC-EX can support. The rails must be double-gapped between DCC and analog zones, but really should be physically isolated such that a locomotive cannot short the DC tracks to the DCC tracks by bridging them together as it straddles the gap between them. This is an important step in allowing use of both types of locomotives simultaneously on the same layout, albeit one that has been segregated between DC and DCC operation. What probably will happen in many of these DCC-EX+DC layouts is that they will implement good-old-fashioned block controls to connect the appropriate DCC or DC source to each track block. This has been going on for formerly block-DC layouts for years. This, IMHO, was an unfortunate choice/omission, since the DCC spec already allows, and some command stations implement (there's no reason DCC EX could not) DCC pulse-stretching to create a variable DC voltage within the DCC waveform, that can control DC locomotives (one speed for all) on the SAME TRACKS as the DCC locomotives! DC locomotives can even be consisted with DCC locomotives, if you speed-match the DCC locomotives to the analog locomotive(s). Don't get me wrong, I like what DCC-EX has added, but I would prefer they had harvested the low-hanging fruit first, and implemented DCC pulse stretching to control analog DC locomotives on the same track, at the same time, with DCC locomotives. That doesn't even need an additional motor driver board!
They feel and to me it also appears that what they are doing has benefits over the 0 zero stretch address function that some use...... ============================================== We do not support 0 zero stretch address function, found on Digitrax and Lenz command Stations on purpose. The constant dual DCC electrical signal may damage certain types of older DC motors if left on for a long time. Unlike Digitrax and Lenz 0 Zero stretch DCC (PWM) signal which leaves the engine lit up and humming loudly with the throttle and engine at 0 speed, because it is receiving a Dual DCC(PWM) aka AC signal, while the EX‑CommandStation TrackManager is dead quiet and at rest at 0 speed. Place any analogue DC engine on our EX-CommandStation with a TrackManager DC assigned track and it sits there dead quiet with lights off Until the throttle speed is increased in either direction and then lights up and begins to move. DCC Loco with DC enabled CV decoder also sits quietly and when the throttle increases the Sound will turn on first then as you throttle up more it will begin moving. You can throttle back until it stops but leave a little throttle speed on say 5% and the Sound will continue to play while it is stopped. Throttle speed response for DC Cabs vary because the DCdistrict track is operating from 0Vdc to 16+Vdc ~PWM waveform signal. CAB’s operating on a DCdistrict with either WiFi Throttles and EXRAIL Automation scripts with Engine Driver Handoff run different DC motors at different speeds. So a script for FWD(50) speed will run at completely different speeds for two different DC motors depending on their resistance and efficiency. One crawls at 50 while the other one runs like a bat out of hell. You can also run a DCC Locos with DC Conversion CV enabled On and run on the DCdistrict, without having to change the decoder DCC address. They will all run on that section of track. DCC Sound Decoder locos with DC conversion enabled may be silent until the track reaches between 2v to 6Vdc then the Sound will start up, and between 3v to 8Vdc the motor will begin to respond and move depending on the manufacturer’s decoder. ======================================================== The other big one to me is you can now use a cheap phone throttle to control a DC loco with EngineDriver. That could be big even on a small layout. Still it is nice having a new option to choose from if one wants to run DC and DCC on the same layout. Looks like you can run upto 8 motor drivers for 8 districts at this time and change between them without needing a physical electrical switch. Sumner
Your point about using DCC EX to run DC locos with their phones running throttle apps is a very good point! And the HW is inexpensive enough to make it worthwhile. The cost is probably pretty reasonable too, compared to good DC power packs that still don't offer wireless throttles. Does DCCEX analog mode support selectable/adjustable momentum?
I like my locomotives to just have a motor, gears (or, in the case of Treble-O-Lectric, drive bands), and wheels. Not all those extra wires running all over the place. Doug
I started off with the Digitrax system, had to change because of the slots issue. So I went with the ESU Cab Control system. When I put on a locomotive that has an ESU decoder in it, it is like, boom all the decoder settings are there on the throttle, instant recognition using RailCom+. There are still some things to improve upon, but that may be happening with the updates that come in over the WIFI. There is no limit to the number of active locomotives, scroll the list and pick a locomotive and go! Unfortunately, RailCom only is almost no different than any other DCC system. You just get the 2 way communication only, which is still much better than what I had with Digitrax. I am not wanting to throw stones at Digitrax, it was a solid system until my layout got too big for it. By too big, I mean more turnouts than the Super Chief system could handle. More locomotives than available slots. It was just too cumbersome to operate using Digitrax. As a hint, find the yard map of the Barstow Yard back in the Transition Era, that is almost fully implemented at one end of the layout.
Even just plain RailCom (non+) has some very effective features. Like programming decoders with complete, rapid, readback/confirmation on the main, while other locomotives are still running. With RailCom implemented and enabled on all locos, you rarely, if ever, need a physical programming track. Also, Railcom enables the TCS command station to minimize the locos (non-RailCom) that must have throttle commands repeated to them, since once a Railcom loco confirms it's current speed, the CS can drop repeated throttle commands for that loco to a minimum. This improves the responsiveness to throttle updates for all locomotives, and increases the practical limit on number of separately addressed locomotives/consists that can be controlled effectively. But unless you're in a large club or show layout, you may not ever realize that benefit. RailCom+ adds the power-up self-identifying feature, so the command station knows who's on the (powered) tracks when it starts.
Well said, I sort of glossed over those points so it would not seem like I was bashing Digitrax, or being overly verbose about RailCom.
Question on running DC locos on DCC layouts? My understanding is that...yes...you can do that. The problem I have read is that you should NOT let a DC locomotive sit idle on on a DCC layout or bad things will happen to it. Is this still true or have things changed over the years? TIA.
Sounds like that is pretty much the consensus view.. https://www.google.com/search?channel=fen&client=firefox-b-1-d&q=run+dc+loco+on+dcc+layout#ip=1 I haven't tried myself. If one went with DCC-EX and there solution to doing this it looks like they addressed the issue but not as simple as putting the loco on the track and using address zero if ones system works in that manner. Sumner
It depends on the inductance in the motor windings. If it is high enough, then little DCC current will be running through the windings at idle (which would be 50% duty cycle on the DCC waveform at "DC idle.") A DC bias is created in the DCC waveform by stretching pulses so that there is no longer a 50% duty cycle. "Coreless" DC motors have very little winding inductance, so there is little to resist current flow while the motor's rotor is stalled, with AC-only voltage applied. These would not do well idling with zero DC on DCC-powered rails. I would ensure that sidings are available to park the loco (and train) where the power can be removed (such as through power-routing turnouts, like Unitrack switches.) Throw the switch to the siding, park the train on the now-powered siding, then throw the switch back to the main, disconnecting the siding from power. It's pretty common on DC layouts to have sidings removed from power automatically when their entry & exit track switches are thrown to the main. Remember, you only need to remove one of the rails from power to de-power a track. Power routing switches simply choose which inner (frog) rail to power, based on which way the switch is thrown.
