I must ask a dumb question about DCC and DC that is often on my mind. I am new to DCC, an old skool N Scaler with dozens of DC locomotives mostly from the 1980s forward, the exception being two DCC locomotives which are a Kato NW-2 and an Athearn 4-6-6-4 with Sound, both factory. The layout I'm building has two throttles I can toggle between -- Kato's newer PWM DC throttle and MRC's Prodigy Advance DCC throttle from 2004. I fear of burning up locomotives through stupidity. What do I need to guard against -- applying DC to a DCC locomotive or applying DCC to a DC locomotive, or both?
the only thing you need to guard again is feeding both powers to the track at the same time .. the locos don't really care, they will either move, or not .... a centre off on your selector switch is a good idea ..
Most newer DCC locos are now "dual mode" meaning they will run fine on either DC or DCC. Your Athearn should be fine, not sure about the NW2, but the documentation (or box) should state if they are dual mode. On the flip side, DC locos don't like DCC.......DCC is a pulsed signal with both positive and negative components......as such, it's making the DC motor try to go forward and backward at a high rate of speed, which usually results in a humming sound. While it won't actually harm the loco, if left in that mode for too long, the loco will overheat, which CAN damage the loco. As long as you don't leave them for too long you should be fine. Older DCC locos DO NOT like DC.
Per your suggestion, I found my Kato NW-2 documentation and sure enough, all is well with it and DC. It has a TCS K3D3 Decoder with auto DC detection, as installed by Kato's Kobo Customs. Cool. I'm off to a safe start with my only two DCC locomotives. Some of my newer DC locomotives are DCC Ready, so I'd guess that they too would be okay on DC after conversion to DCC if I mistakenly tried to run them on DC. So, I must guard against a DCC signal reaching DC locomotives, but it's not instant death should it happen for a brief time. I added an orange LED to my panel to catch my eye when DCC is on line.
Most DCC locomotives will run on DC with no problems assuming DC compatibility mode is turned on (most of the time enabled by default but can easily be changed in JMRI or CV) Digitrax Zephr, one of few systems, enables running a DC loco (DCC addr 0) however there are mixed reports on whether it is a good thing for the motor. IMHO, I'd avoid running a DC loco on a DCC track. Had run my DCC BLI F3 for a few months using a Kato DC pack b4 going to DCC permanently. Definitely use a center off switch..
As has been mentioned, most DCC decoders will run on DC. Contrary to popular belief this has actually always been the case. Some of the earliest sound decoders would not run on DC, so manufacturers with sound decoders that would run on DC started to call them "dual mode" decoders to emphasize that fact. Before then, however, most decoders would run on DC even though they were not advertised as "dual mode." There are a few decoders that can be damaged by running on DC (some of the early Paragon3 had that issue). On of the reasons being that most DC power packs do not put out "smooth" DC and their peak voltages are much higher than 12 volts, so an out-of-spec component that has no problem with DCC voltages can be damaged by the peak voltage pf a DC power pack. There is, however, a very good chance your DCC locos will not run on your Kato power pack because it is PWM. PWM tends to confuse DCC decoders.
Both you and @wvgca have recommended that. Is that to prevent the DC and DCC throttle outputs from combining for an instant? I can imagine that'd be a bad thing indeed. I didn't think of that when I built my panel. Speaking of center off functionality, the Kato pack has a lever to set direction and has a center off. Initially I disliked it, but it's grown on me. It's handy when I'm working on block wiring or when I'm distracted by a phone call or whatever, knowing that the throttle is sending no current to the rails.
Trying to run a DC loco with DCC is roughly the same as connecting the track, on a DC layout, to the AC terminals on the power pack. IxNay on AtHay Doug
Yes, you are on target No contact bounce! Used a center-off for OPS and Prog track section switching -- essentially same reason. Did the exact same thing... When ran under DC--Always powered up and shut system down with direction lever in center position using the Kato 28-018 (think that's the same Kato power pack you have??). With DCC, all throttles configured to prevent accidental directional change and must come to complete stop before reverse.
Sometime later I need to think through a programming track solution. My MRC Prodigy Advance has separate outputs for "Main Track" and "Program Track". I don't have room for a programming track, so might rig up a simple segment of track on a board that I can set on a little table nearby. I suppose I could wire a block on my layout to also serve as a programming track. I'm confident in wiring, but as a DCC newbie with an aging brain, I'd be concerned that I'd somehow overlook the track's changeable status and visit ruin upon a locomotive.
Having a small 2' x 4' layout, it was hard to decide if and where. Ended up with about 8"-9" in length via isolating joiners so only good for quick programming especially with Paragon 3 decoder based locos. Followed and modified the DCC wiki on prog track.. Added a NJI 2100 2 LED dwarf signal at end of spur to indicate whether the section is connected to either main (Grn) or programming (Red). https://dccwiki.com/Programming_Track If space permitted, would have followed wiki exactly with isolating segment and added just the bi-color LED. Without an isolating section, as in my case, extreme care so loco does not cross. In the old HAM days... Maximum Smoke Minimum Signal... The spare 4PDT connections (initially for isolating track) will eventually control a SG90 servo via an Arduino Uno that will move a protection gate to block passage when section is in PROG state. While not absolutely necessary, think it will add a little fun to the electronics side. Similar to your thinking, and in cases if wanting to read entire CV sheets in JMRI, will have an extension 2' x 4-6" that will attach to the side frame. An opening on the side frame will have a RCA phono female feeding the PROG output of the base station in which a male, connected to the extension track, plugs in.
I kept the keyboard drawer off my last desk.......My plan was to use that mounted under the layout to do a programing track. Option B is to sacrifice a track on my turntable.......I have several that aren't under the loco service buildings. An option for you is to use the same technique as the you are using with your DC/DCC dual power.........take a section of track and isolate it, then add a toggle that can choose between program and normal DCC.
Why would you need to sacrifice the track. Do you mean that you would have to keep it open in case you needed it? I use ... http://1fatgmc.com/RailRoad/UP Canyon Division/page-13.html .. a siding on the test track and will do the same on the main layout, pretty much how Mike outlines it here.... It is quite easy to throw the switch to make that section of track a program track or part of the main. It is recommended to have a section of switchable dead track between the main and what can be the program track. I didn't do that but for the engine to run out to the main the one turnout would have to be thrown in my case between the siding and the main. I always program on the right end of that track so no way the engine is going to get down to the turnout and then throw it and head to the main so I feel comfortable without the short section of buffer track in my case. Some of the locos creep a fair ways so I'd try and have it 1 1/2 to 2 feet in N scale for that movement if possible. That might present a problem if a turntable track isn't very long. Sumner
With such a small layout, I would have the entire rest of the layout wired through 2 poles of the 4PDT switch so that when it was switched to programming it would just turn off the rest of the layout. As others have mentioned, if you use a block on your layout ideally you want a buffer track between it and the rest of the layout that is turned off when programming (or turn off the rest of the layout like I suggested above). The reason for this is two-fold. If you accidentally cross the gap between the program track and the rest of the layout while programming, you can program everything on the layout. Even worse, you can damage your command station because you'll be shorting the high powered track output to the programming output. (just turning off the rest of the layout won't prevent programming everything if you cross the boundary, but it will prevent damaging the command station).
Thing of it is we get used to say an Orange LED, at least I do or would. For instance whenever I am working on DC/DCC wiring, I always test with my one still really good DC locomotive and my Tech II power pack ( which I also use the AC terminals for throwing my turn outs ). So after finding some shorts and fixing them. I got distracted by it, and I'll be darn, when I went and hooked up my DCC for the NCE Powercab, I forgot to REMOVE my DC locomotive, and it makes a horrible sound too. Or mine did. Even our best intentions don't work out. Thought for sure I fried one or both locomotives, but I got lucky as I have a foot switch I immediately turned OFF power to everything. To me, and this is me ONLY, DC and DCC don't mix. That's what happened when I forgot to remove my DC locomotive after switching it over to DCC. So I had a DCC and DC locomotive on the tracks at the same time. I was not happy, but got lucky! I would think since you have mostly DC locomotives, your mainly going to be running DC and Not DCC? Also because of your control panel you built for DC blocks? To me they are like Oil & Water ( is that right? ) and don't mix. But that's just me! Luckily I am now completely DCC, and hopefully in the future I'll just use an older DCC locomotive when I do more wiring for testing? Main thing is good luck, and have fun! Oh yeah, be careful
Yes, so I think running DCC will likely be a big deal to me for the foreseeable future and I'll be pretty aware of it, orange warning LED or not. Though as a double safety, I could hang a sign on strings above the layout at eye level, roughly 6" x 12" with a giant DCC emblazoned on it.
Yeah you have posted many times that you are a Big fan of DCC Saying things like " You DCC people are so lucky", think this was when you were wiring 24 block switches or so So I guess you will be slowly switching over to DCC in the future, building your rooster of DCC equipment? Are most of your DC locomotives DCC ready? I've said it many times, it's why I enjoy the hobby now. It took me a really long time, because of cost, and I also have such a small layout compared to others. I only had Two Bachmann F7 DCC locomotives for 3-4 years and a Bachmann EZ Command Control, which I still like a lot, but no CV programming and such. had no idea what I was missing. Now with the NCE PowerCab and 9 DCC locomotives I am a very happy camper. Along with the help of members here explaining to me how to wire Momentary Switches for Turn Outs and for DCC power drop locations. Just wear a Dunce hat but put DCC on it Have fun! Just think your entire control panel of blocks may be a moot point one day? I think I am gonna get that NCE Powercab programming track board one day. Right now I have to disconnect my Main line and hook up the Programming track line. But I don't use it much right now. Been focused on wiring and such. When I get back to playing/learning the NCE PowerCab then I'll think about a permanent solution. Sorry I rambled, have fun with DCC and DC
I've been an N Scaler since 1968. Most of what I run was bought from 1980 forward, so most of it is not DCC Ready. I'm okay with it though, having been satisfied with obsolete things for most of my life. My DC stuff runs well and so do my two DCC locomotives. I'm looking forward to expanding my DCC locomotive count, but at this point, I don't see anything I thirst for. That may change ......
Once you do a couple putting DCC into an older loco that isn't 'DCC Ready' isn't that hard and doesn't take that long to do and is actually quite rewarding. I'd strongly suggest giving it a go. An afternoon of work and you now have a DCC loco for $18 to $30 if you don't want sound. Hardly any of the locos I've bought were DCC Ready but I'm converting them over time. I have some that I've done ( HERE ) ................................................ but got my nerve up by looking at Brad's installs ( HERE ). He has tons documented!! Look at all that he has up on the left side of that page. Sumner
