Advice please on a simple DCC system

[Londontram]

I'm an old die hard set in his ways annalog man with my model trains. I'm happy with this it fits my needs totally but I  find I'm contemplating a new project that I can see that DCC would offer all the solutions to the problems my new project would face.

 I'm building Scottish single track main line with a passing loop at a station. With a maximum of only one train moving and only two trains on the track at the same time one in the loop so annalog is fine for that.

 But in the words of the great Monty Python "Now for something completely different"

 

Being an old tram man I'm thinking of a small table top roundly roundly with not trams this time but Trolley buses using a Faller style steering system but having the trolley buses actually worked by power from the overhead. 

Building this is no problem but I would like to have maybe 4 or 5 buses at verious points of the layout and even cases of one bus over taking another.

 So is there a very simple basic DCC set up which would let me run as many as say 5 or 6 vehicles.

  I'm not worried about sound or lights ect just the basic control of the buses. Being new to this I would very much appreciate any help and advice you could give me

[Nigelcliffe]

Your description of buses not colliding and overtaking is not a "simple" system (regardless of analogue or digital).   So you'll need to do some thinking on how to do it.   Somehow your "system" needs to have some knowledge of where the buses are in relation to each other, and the correct actions to undertake.   That might be a central "brain", or it could be local control of sections of "track" (tramway). 

 

In terms of running 4 or 5 buses, any DCC system can do that.    But the automated stuff will constrain which systems can work with the automation - many will be unable to integrate with the automation hardware.  

 

Electrically (analogue or digital), unless your overhead is quite clever, you've got a problem of "where's the other wire".  A simple overhead provides one wire for the power.  The other wire has to go somewhere else, such as a metallic road (and metal wheels).  

 

 

- Nigel

 

[Oldddudders]

Nigel's advice is very sound, but one basic difference between DC and DCC is choice of direction. With DC, all vehicles travel in the same direction, according to the controller. With DCC each loco/trolley can go in whichever direction you set, so the scope for head-on collisions, with distressing results even at low - trolleybus - speeds, is substantial. Nigel's advice about a 'brain' being essential is spot-on, if you don't expect to run everything by direct control. And, trust me, even controlling two locos or trolleys at once is more taxing than you might think. 

 

Eheim were the traditional go-to manufacturer for HO trolleybus sets, bit and pieces, and their twin-conductor overhead would make life easier in construction. When they were last in business I know not.

[Londontram]

Thanks for the advice its all going into the pot. As to wires I've built overhead for my previous tram layouts and as trolley buses work of twin wires having a return and insulating it is no problem and I've already done it with alternate direction wires off a common span wire there's ways round that. With a train set of points the points them selves can isolate a section and you can also isolate sections but the Frog "Point" on the over head wire tends to work best with an a open frog the frog is positioned to let the bus/tram trolley plole/poles be dragged through an open frog following the direction of the vehicle so having an isolating frog is not really an option neither is isolating breaks.

 I wasn't looking at automated running either but would like to have bus number 1 sat at a stop and bus number two pulled up at the stop behind it then bus number one moves off. At one end would be a terminus with a turning circle and I'd like if theres 2 buses sat at the terminus maybe a 3rd bus on a different route can overtake them and move off and the first of the other buses follow after a suitable time.

  So as I say it's not going to be a case of buses running at the same time but more of a leap frog ability without having the need to have lots of isolating sections.

Edited September 22, 2021 by Londontram

[SamThomas]

As you have overcome any of the issues regarding twin powered wires & "overhead points" & have no need for automation makes your choice of a DCC system easy.

 

Before you go down the DCC route just bear in mind that DCC requires very good pickups - however, use of something like "Track Magic" will help as will the use of decoders with some form of "Power Pal".

 

Your next choice will be desktop contrioller or hand controller.

 

Handheld - I would recommend looking at the Roco Multimaus - nice single hand operation, illuminated display, more than enough space in the stack (or memory) for you to recall your fleet easily & you can name them (not possible with the Powercab** which many people swear by) "Red Bus", "Green Bus" & so on. You could also look at the Roco Z21 which is expensive but you can picture your fleet to find them & you can use a tethered handset, wi-fi handset or a smartphone/tablet.

 

Some of the Gaugemaster systems are pretty good too - also alvailable as wireless.

 

Lenz is excellent but like the Powercab, in need of updating, but then again Lenz is reguarded as the Father of DCC.

 

** The Powercab is a well respected & popular bit of kit, especially on here. Personally, I would not use one - I find the handset too "clunky", don't like the thumbwheel speed control & because you cannot name your fleet a little bit "old hat" & well overdue for an update.

 

Personally, I have no experience of current desktop controllers.

 

 

Edited September 22, 2021 by SamThomas

[Nigelcliffe]

2 hours ago, Londontram said:

Thanks for the advice its all going into the pot. As to wires I've built overhead for my previous tram layouts and as trolley buses work of twin wires having a return and insulating it is no problem and I've already done it with alternate direction wires off a common span wire there's ways round that. With a train set of points the points them selves can isolate a section and you can also isolate sections but the Frog "Point" on the over head wire tends to work best with an a open frog the frog is positioned to let the bus/tram trolley plole/poles be dragged through an open frog following the direction of the vehicle so having an isolating frog is not really an option neither is isolating breaks.

 I wasn't looking at automated running either but would like to have bus number 1 sat at a stop and bus number two pulled up at the stop behind it then bus number one moves off. At one end would be a terminus with a turning circle and I'd like if theres 2 buses sat at the terminus maybe a 3rd bus on a different route can overtake them and move off and the first of the other buses follow after a suitable time.

  So as I say it's not going to be a case of buses running at the same time but more of a leap frog ability without having the need to have lots of isolating sections.

 

Test reply (RMWeb says "you've been blocked" and I can't see anything in my reply which would be a rude word...). 

 

 

 

 

[Nigelcliffe]

( Here's the first half what I tried to post before RMWeb said "you've been blocked".   Because I've no idea why its blocking me... )

 

You say "turning circle".   Is this a situation where the bus does a turn and returns along the same street on the same original wires, or are the wires still in a circle (a somewhat squashed circle) ?    Because if you return to the same wire, the left-wire is now the right-wire, and some form of reversing of current is required.  This is do-able, but more kit.  

 

If you are planning to manually drive the buses, then any system will do the job.   However, I suggest that driving each bus manually (select number, alter speed, etc..) will become a bit tedious on any handset.   So, I propose the following as a way of "push button" operation, and keeping things fairly cheap.  

 

Well known kit, think it does all you ask.   NCE PowerCab plus one NCE MiniPanel and at least ten, possibly fifteen to twenty, push buttons.   

The PowerCab is a well known introductory system, works well, does most things.   The MiniPanel to give you push-button operation.    
Initially, set up each bus on the Powercab to have an address, and give the bus a bit of momentum (CV3/CV4) so speed changes are not "instant".   That gives you manual driving, and allows you to work out what speed setting gives a good bus "running speed". 
Then, program (using the PowerCab handset) the MiniPanel and its buttons.   Each bus needs at least two push buttons, labelled "stop" and "go".  For the Stop button, it is programmed to "select address X, send speed zero (stop)".   For the Go button, it is programmed to "select address X, set forwards, send speed (running speed)".   Then, your panel has push-buttons for each bus labelled "stop" and "go".  You can choose to drive them manually on the PowerCab, but can also drive on the push buttons (or a mix of button and power-cab).   The optional additional buttons (hence: fifteen, twenty), would allow different speeds for each bus (go slowly, go medium, go fast), or potentially forwards/reverse.     The MiniPanel has space for 30 buttons, and a small number of MiniPanels can be connected at the same time.  

 

 

[Nigelcliffe]

 

( And here's the second half of the blocked reply....)

 

For any setup, In each bus, fit a small decoder (if unsure what to fit, buy a Zimo decoder of the size that fits), and ideally add a stay-alive module (the Lais units sold by Digitrains for £15 each would be my first choice, if space in the bus permits).   
The stay-alive module has to be connected to the decoder.   This is either soldering onto the decoder (small solder pads on decoder), or, can use a Next18 socket (Digitrains will sell you one) that you solder all the wires to (motor, pickups, stay-alive), and then plug a Next18 decoder into the socket.   If there is space, the Next18 socket would be my choice, its a far simpler soldering job to connect everything up.  But, it costs some space, and if tight, then direct wiring things will go into smaller spaces.    
The Zimo decoder will work almost any motor smoothly, and the stay-alive will see the trolley-bus over any loss of pickup at junctions or momentary drops in power from the overhead.   

 

There are optional features in Zimo decoders such as "constant stopping distance" which might be useful to you, possibly combined with ABC braking.  With the latter, a very simple circuit (60p worth of diodes) is switched in/out of the supply to one wire (rail), and this tells the decoder in that section to come to a stop (gently, following its braking settings).  That could be made to work to stack-up buses at a stop, but would require the braking zone extending for each bus in the stop ahead of the one arriving - fairly easy to do with a few switches and relays if you felt that feature was desirable.  To implement you need sections in your overhead wiring so that a section can be set to "brake to stop" or "normal running".  

[Londontram]

All food for thought thank you I shall reread it a few times to get my head round it and look into it further

[SamThomas]

5 hours ago, Nigelcliffe said:

There are optional features in Zimo decoders such as "constant stopping distance"

5 hours ago, Nigelcliffe said:

 

Not exclusive to Zimo - also available from Lenz & ESU (& probably others).

[Nigelcliffe]

16 minutes ago, SamThomas said:

Not exclusive to Zimo - also available from Lenz & ESU (& probably others).

 

True, though Lenz made a complete mess of "constant braking distance" - their algorithm has locos crawling along at snail pace to reach the stop point, or stopping abruptly from a middling speed.   Whereas other makers have done a much better job of it.  

 

- Nigel