With your current setup there is the chance, however remote, to cross DC and DCC if you forget to switch one of your blocks to DCC and cross that block's boundary. With the 4pdt switch switching out the other cab that eliminates that possibility entirely, though you still have to switch every block to the DCC cab to be able to run in them. Using the 4pdt switch to switch both cabs to DCC additionally eliminates the requirement to switch all blocks to the DCC setting.
CSX RobertThe one change I would make to your setup is to replace the DC/DCC switch with a 4pdt and either switch throttle A and throtttle B to DCC, or switch one to DCC and the other off.
It has occurred to me that having the DCC wiring branch off of just one of my power-pack electrical paths and not the other is a bit weird, but I don't think it makes any operational difference.
Please clarify the reasoning behind your suggestion. I'm very suggestible.
-Matt
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.
crossthedogWhere the DC/DCC switch comes in: The wire to throttle A is interrupted with yet another DPDT switch, which throws the control either to the throttle A power pack or to the NCE Power Cab DCC outlet. In order to run DCC, I have to plug in the NCE unit, plug in the handheld throttle, and throw the DC/DCC switch, AND throw ALL the panel swiitches to the Throttle A position.
The one change I would make to your setup is to replace the DC/DCC switch with a 4pdt and either switch throttle A and throtttle B to DCC, or switch one to DCC and the other off.
Wolf359Wolf359 wrote the following post an hour ago: crossthedog True, but I use a center off DPDT to switch between DC and DCC anyway. I don't want any chance of there being even a moment where the current is wrongly directed. I always walk away from my layout with that switch in the center position. Nothing runs nowhere, nohow, until I consciously decide to flip that switch to one or the other mode. That's what I want to do, and I want it for all of the roundhouse stalls and parking spots so any engine can use one of them at the flick of a switch. I also want it to control blocks so for example if I were to have friend over who enjoys model railroading, he can have a DCC engine doing one thing on the main line, and I can run a DC engine in another area like the yard or vice versa.
crossthedog
True, but I use a center off DPDT to switch between DC and DCC anyway. I don't want any chance of there being even a moment where the current is wrongly directed. I always walk away from my layout with that switch in the center position. Nothing runs nowhere, nohow, until I consciously decide to flip that switch to one or the other mode.
That's what I want to do, and I want it for all of the roundhouse stalls and parking spots so any engine can use one of them at the flick of a switch. I also want it to control blocks so for example if I were to have friend over who enjoys model railroading, he can have a DCC engine doing one thing on the main line, and I can run a DC engine in another area like the yard or vice versa.
My block bus wires all come into the main panel board, where DPDT COs determine which of two power packs/throttles controls them. This is done by having each switch on the panel wired to two Miniatronics terminal strips, and the two strips then wire out to the two power packs/throttles. This way I can run DC with a friend, keeping two locos on separate blocks and controlling them with two throttles, or more likely, run one train on the mainline loop while building trains in the yard or spotting cars for industries on the branch.
Where the DC/DCC switch comes in: The wire to throttle A is interrupted with yet another DPDT switch, which throws the control either to the throttle A power pack or to the NCE Power Cab DCC outlet. In order to run DCC, I have to plug in the NCE unit, plug in the handheld throttle, and throw the DC/DCC switch, AND throw ALL the panel swiitches to the Throttle A position. And all my DC engines come OFF the layout before I do any of the above. It is therefore very unlikely I will burn up any of my DC engines. I have a small layout, so this works for me, but it may be problematic on a large pike where a loco might have been driven into a shed or a tunnel and been forgotten about.
Matt
gmpullman Maybe I'm in the minority here but I believe "blending" DC and DCC on the layout isn't a good idea, IMHO.
That is where I reside. No blending.
Rich
Alton Junction
Wolf359he can have a DCC engine doing one thing on the main line, and I can run a DC engine in another area like the yard or vice versa.
Sorry but I still believe as I mentioned in my first reply that this is a recipe for disaster.
All you need is a locomotive or passenger car with metal wheels (lighting capability) to bridge a gap while the other track section is switched to DC/DCC or vice-versa, and you'll either be back-feeding one or the other to the throttle (DC) or command station (DCC). I'm not aware of any DCC command stations that are protected against a reverse current flow.
Conversely, you could bridge a gap and suddenly be feeding 14-16 volts of the type of AC current that is constantly output from the DCC command station. If the phase is mismatched you could possibly double the voltage getting to a locomotive.
Maybe I'm in the minority here but I believe "blending" DC and DCC on the layout isn't a good idea, IMHO.
Switching the entire layout from a DCC or DC source is at least a lesser of two evils but you still run the risk of having a DC locomotive seeing DCC current which, if left for a while will melt armature windings.
I could be all wrong, though.
https://cs.trains.com/mrr/f/744/t/177102.aspx
Scroll down to about the middle of the page here:
https://wiringfordcc.com/intro2DCC.htm#a28
To: Using both DC and DCC on the same layout
Cheers, Ed
Wolf359 and I want it for all of the roundhouse stalls and parking spots so any engine can use one of them at the flick of a switch. I also want it to control blocks so for example if I were to have friend over who enjoys model railroading, he can have a DCC engine doing one thing on the main line, and I can run a DC engine in another area like the yard or vice versa
Not a good idea! If you accidentally cross the boundary between a DC block and a DCC block, you can fry the DCC booster ciruit. If you want to be able to run either DC or DCC, the best thing to do is to have a single switch that switches the entire layout between DC and DCC.
saronaterry If you are looking for a brand recommendation I prefer Miniatronics. They come in multipacks and are pretty much bullet-proof. Terry
If you are looking for a brand recommendation I prefer Miniatronics. They come in multipacks and are pretty much bullet-proof.
Terry
Yes, that's exactly what I want. I goofed, I should have been more specific.
crossthedog True, but I use a center off DPDT to switch between DC and DCC anyway. I don't want any chance of there being even a moment where the current is wrongly directed. I always walk away from my layout with that switch in the center position. Nothing runs nowhere, nohow, until I consciously decide to flip that switch to one or the other mode.
That's what I want to do, and I want it for all of the roundhouse stalls and parking spots so any engine can use one of them at the flick of a switch. I also want it to control blocks so for example if I were to have friend over who enjoys model railroading, he can have a DCC engine doing one thing on the main line, and I can run a DC engine in another area like the yard or vice versa. I actually prefer older, DC engines, but some of the ones I'm interested in only come in DCC with sound, and as I said elsewhere, I have over 100, so upgrading all of the DC engines isn't exactly budget friendly.
wjstix Unless you have hundreds of engines, I doubt you really have too many to convert to DCC. Remember you don't have to do sound. Regular 'motion and light' decoders aren't all that expensive; some online dealers give you a discount if you buy say 5 at a time of the same decoder. If your engines were made in this century, they probably have a DCC receptacle already in place.
Unless you have hundreds of engines, I doubt you really have too many to convert to DCC. Remember you don't have to do sound. Regular 'motion and light' decoders aren't all that expensive; some online dealers give you a discount if you buy say 5 at a time of the same decoder. If your engines were made in this century, they probably have a DCC receptacle already in place.
I have over 100 locomotives, most were fixer-uppers that I got cheap because I enjoy working on them, and they're usually all that I can afford. So, buying 100+ decoders isn't exactly something I can afford.
crossthedogTrue, but I use a center off DPDT to switch between DC and DCC anyway.
I mentioned further down that if I were setting up something like that I'd use a dedicated plug and socket so that only one system could be plugged in at a time.
How often would an operator be switching between DC and DCC during one session?
Bottom line is, choose one (DC) or the other (DCC) and stick to it.
Stix has the advice I'd suggest. Install the needed decoders and be done with it. Plus when installing the decoders it gives you a chance to go over the engine and tune up the mechanicals.
Regards, Ed
gmpullmanWouldn't necessarily have to be center off.
I bought some of my DPDTs expensively. When I needed some reversing four-post switches, Kevin recommended some made by Carling, and I like those a lot. I got them from Grainger and didn't have to pay shipping because I picked them up at a nearby location. They were very reasonably priced and they work well and are NOT STIFF to throw. When I need more switches I will buy Carling from Grainger.
I think you and I are on the same page. I use DPDT C off switches for all my blocks. I also run dual mode, DC or DCC and not all of my locomotives have decoders.The switches I use are the tiny type that mount in a ¼” hole. I have a total of 84 switches on my control panel, not all DPDT. I use SPDT C off for my switch machines and SPST for lighting control.This is my layout on my control panel.Each roundhouse track and the turntable have a DPDT C off switch as do all my blocks.Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, CaliforniaGrowing old is a bummer, aging is definitely not for wimps.
Terry in NW Wisconsin
Queenbogey715 is my Youtube channel
Wolf359Based on the plans I've come up with so far, I'm thinking I'll need somewhere around thirty switches,
I'm sorta missing something here. If you are looking at "block control" which is the usual arrangement for two-cab DC track wiring I can see the need for DPDT center-off switches. I had scores of them when my layout was DC.
If you are contemplating having a DC throttle and a DCC command station you would need one DPDT switch with a pair of wires to each output (DC and DCC) and the center pair feeding the rails.
If you then want to isolate sections of track as you would for DC especially you could use simple SPST switches (common rail) or preferably DPDT to isolate both rails.
Feeding DC and DCC to each block would not at all be a wise idea. Any DC current inadvertently fed back into the command station or if you had an errant locomotive bridge a rail gap and crossed into a block where the switch wasn't set to the same "supply" could be electrically desastrous.
I ran my latout for a year or two with all the DPDT center off (plus some rotary switches for yard and engine areas that had three or even four "cabs") without any problems BUT I completely disconnected the DC throttle(s) while running DCC and vice versa.
Can you elaborate more of what you would require for DC cab control.
You would build and wire your layout for that requiring electrical blocks for the track segments that need to be energized or dead as needed.
Once that is installed, debugged and working you could then switch over to the DCC command station either using a plug and socket or a DPDT switch. Wouldn't necessarily have to be center off.
I bought many from this outfit:
https://led-switch.com/collections/switches
Good Luck, Ed
I use the mini DPDT Center off switches, they’re rated at 6 amps. I’ve been buying them for years from LED-Switch.https://led-switch.com/collections/switchesMel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, CaliforniaGrowing old is a bummer, aging is definitely not for wimps.
Hello all, I'm going to be moving soon, and as a result I'll finally get to build a "real" layout, as opposed to the small, dining room table setup I have now. I was wondering if anyone could a recommend a good (preferably inexspensive) DPDT switch with a center off position that will work on a layout that will use both DC and DCC? Most of my locomotives are DC, (I have too many to make conversion viable) but I have acquired a few DCC with sound engines, so I'll need to be able to switch between DC and DCC without frying anything. Based on the plans I've come up with so far, I'm thinking I'll need somewhere around thirty switches, most for a 14 stall roundhouse and yard. I should also add that I'm a "lone wolf" opperator, if that makes a difference. Thanks.