A dpdt switch can select between ONE DC pack which can run one loco, and one DCC booster that can run many locos.
How will you handle multiple DC packs with one dpdt switch? If you are proposing one dpdt switch per block, people do this but it has to be done carefully to avoid "letting the smoke out" of equipment. I don't quite understand the damage that can be caused (the DCC standard actually defines a DC-powered block to mean a stop-block) but folk do warn against mixing them up.
When i was pondering doing this I ended up with a design where the Big Switch actually controled a relay on every block that made sure ALL blocks were on DC or ALL blocks were on DCC.
lvanhen wrote:When I got my DCC I had a double loop with crossover & sidings. I put a dpdt center off switch between the track connections & the packs. I can run DC or DCC, but NOT BOTH AT THE SAME TIME!!! I can still run the old locos or the new ones, but not together. My
There's no crossovers, but a few sidings. The only thing that I thought about in the future is signal control, but it's not a big thing right now for me.
On the DC side, I've got a Tech II dualpower 2800 and a Controlmaster 20. The dualpower runs basicaly two loops. The controlmaster shares the yard with side 1 on the dualpower.
What I want to do is put the DPDT in between the MRC's and my future DCC system. So I don't have to add any other wiring, except to beef up the mains possibly. The mains are 18 gauge and the feeders are 20 gauge, both stranded.
So the ultimate result is...flip a switch one way and run what I have now, or flip it the other way, take all the DC equipment off and run guests locos and hopefully, new aquisitions that are DCC ready.
The only thing that I see as a problem now is turnout control....how did you handle that?
Bob Berger, C.O.O. N-ovation & Northwestern R.R. My patio layout....SEE IT HERE
There's no place like ~/ ;)
DCC can draw a a lot more power into one block than DC (think three sound-equipped locos) so it generally needs heavier wire, especially on long lengths.
And as mentioned above, if you ever want block detection you'll need different devices on each type, so separate wiring would help.
But I'd be worried they may interfere with each other. Where will they meet up? Actually on the rail (separate feeders for both) or will they share feeders?
DCC can have devices out on the layout attached across the DCC power feeds: local stationary decoders controlling turnouts etc. Put DC on the rails which feeds back thru the DCC wiring to them....
I'm betting the only folk who have been successful with dual-mode layouts have simple systems with nothing but throttles and trains. the moment you want block detection (as compared to spot detection using infrared etc), signalling, transponding, autoreversing, power sector protection, turnout control, turntable driving, or a host of other features on your layout, then dual mode will make them difficult or impossible, regardless of how you wire it.
luvadj wrote: That's what I'd like to do...I know I can't run both systems (DC & DCC) at the same time, but that wasn't my intention. Would it be advisable to run new wiring for the DCC side?
That's what I'd like to do...I know I can't run both systems (DC & DCC) at the same time, but that wasn't my intention.
Would it be advisable to run new wiring for the DCC side?
I didn't, and have had no problems for 2+ years.
DC is 0 - 12volts fwd to the track. DCC is a constant encoded 14 volts which intructs the decoder how many volts to send to the motor. As such, they are incompatible, and accidental damage can result by mixing.
A large multipole 'Transfer' Switch can throw all blocks at once, and some DCC makers provide a single DC address to play with, but the best advice is NOT to MIX. (Separate everything).
The BEST solution so far, are QSI equipped engines, whose DCC modules are DESIGNED to run on both (and costs $100 for their module). The $100 icludes a $150-$200 speaker installation, plus They'll run on DC NOW, and DCC when you get around to it.
Separate Remote Controls don't work on different brands of TV, either, but we don't have a problem with that - (perhaps it's because it doesn't burn ouT the TV).
I wired a large HO scale club layout so members could run using either DC or DCC, but NEVER both at the same time due to the risks involved in trying to do so.
In our case, a large, central power supply is used for both modes, so it was a simple matter of routing the power output to the layout through an appropriately labeled toggle switch. If members want to use DC, they put this toggle switch into the BLOCK position and power is fed only to the Cooler Crawler hand-held controllers; if the switch is put into the DCC position, power is fed only to the DCC boosters.
A similar system could be used on a home layout by feeding your output from the DC throttle and DCC booster to the track through a double-pole, double-throw toggle switch that would select between DC and DCC modes, but never allow both to be connected to the layout at the same time.
Our experience has been that once a new member sees the advantages of DCC, they install decoders or purchase new locomotives and never use the DC mode again.
Bob,
If I understand this right, you have two seperate loops, each with it's own DC power pack. Is there any track connections between the two loops? As several other folks have mentioned, you can wire a DPDT toggle switch between the power pack and the track - Flip it one way and you have DC control, the other way will attach the loop to the DCC system.
And as others have mentioned, you can 'smoke' your DCC stuff if you cross a gap between DC and DCC area of the layout. If you dod not have any connection between these zones - You are safe.
I once helped a LHS set up their 'test track' for dual DC/DCC operation. It consisted of two tracks with a crossover between them. I suggested they get rid of the crossover and just have DC on the from track and DCC on the back track. The argument was that they wanted to 'test' an engine going through the crossover. So, I wired it as they wished, with a toggle switch to switch the track power to either DC or DCC. Then they gapped the short lead after the crossover and wired it as the 'programming track'. I explained there was a good chance that they would blow up a decoder if something ran over the gap, but they marked it with a thick red line by the gap, and explained to me that I was just worring too much. The next Monday, I get a frantic call at work from the LHS. They overshot the gap and now they had 3 BLI DCC engines not working!
I stopped down at lunch time and was able to 'recover' the engines by doing a 'reset' on them. This happened one more time that week, and then they built a big 'bumper out of cork to block entry to the programming track!
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
If you can throw a big switch and go from DC to DCC then that will work, so long as it is set up so you can never screw up and have both connected.
What i found is the practicalities don't work. If you ever want to do block detection, then DCC block detection is incompatible with DC block detection. (All this stuff about DCC being just one big block is only true in layouts with no signalling). You end up with two parallel sets of wiring. As Don says, run just one DC loco at a time in the DCC address 0.
Jeffery;
At first I couldn't see the wiring and then I caught the dual throttles. I can't do it that way because each of my throttles runs a seperate loop.
What I was thinking of was wiring all new buses and feeders (Does anyone have a suggestion for wiring this idea?), re-install the DC controls and then adding the DCC.
In other words, I wanted to run the original DC and blocks with the older equipment and then via a switch, go to DCC and run the newer equipment on the same layout.... I don't want to run both at the same time as I'm aware of the risks involved with running them together.
DCC WIRING is essentially one BIG block. One can have multiple Throttles - or one for each GUEST.
DC WIRING divides the layout into "block" sections, which are activated individually by mechanical toggle switches. Since most mechanical switches have two positions (on-off) or (throw one-two), most all DC layouts are limited to two Cabs.
DCC reqires a decoder module per engine. The Power source is contantly on full, and the decoder controls the voltage going to the DC motor.
AS SUCH they are incompatible. Some DCC manufacturers have a slot for running one DC engine and others build-in protection to their DCC modules, but by and large they are incompatible. ATLAS products have an internal switch to throw. QSI electronics can run on both (for about $100 each.
BEST to wire-in blocks that can be trown DC or DCC. I can throw blocks for CAB A or CAB B, so DCC can be added by installing DCC at CAB B. I can add warning lights per block as reminders, if I wish.
Far more important iS he the TYPE of turnouht. I will need 100% frog isolation for DCC, which means I will have to CONVERT or use "DCC friendly" turnoutsl. Should I be starting out, most turnout makers are converting over their product to 'dead' frogs.Peco calls it an 'Insulfrog'.
RECOMMEDATIONS:DC for one man operation; QSI equipped engines; 'DCC friendly'(insulated frog)turnouts. DCC is here today, but will be obsolete someday.DCC if you have the money and plan to have more than one guest as an egineer.
. Additional cabs cost $$.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
I've decided to take the plunge finally and wire the layout for DCC. As most of the locos are older, I want to keep the DC side wired and ready to run. At the same time, I'd like to start updating the layout and get 2 or 3 DCC locos.
Does anyone run dual mode and if so, how did you wire the layout and does anyone have any advice on the pitfalls and/or problems of doing a dual powered layout?