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Discussion Starter · #1 ·
I recently purchased a Dynamis DCC on recommedation of local dealer. He has installed installed decoders into three locomotives. I have a test straight as it suggests in the manual (not connected to the layout), and I can get the loco to go backwards and forwards. That much I understand but the rest is a mystery.

I think the documentation with Dynamis and the Decoders is really poor for someone who has no knowledge of the subject

I have read through many articles and have become more and more confused. I dont mind a challenge and am prepared to learn. Can those experts give me simple guidance, without jargon. I am sure I am not alone in my state of bewilderment.

Background - my model railway is in a loft conversion (self built), 16 m around the room principally Hornby OO. I have 7 locomotives all set very loosely in the 1950's (yes I know predictable). I have in preparation put in place (bell) wire all around under the circuit to ensure no dead areas when I convert to digital. I have read in one thread this is not sufficient, and should use household cable with just short tails of fine cable, is this correct? Would 0.75 or 1mm be more appropriate?

Lighting on the circuit, and turnouts I would like to be digital in the future. I am reluctant to have more locos with decoders until I understand the potential of dcc (sound being just one I have read about) , but at the moment using the locos correctly is the first step.

Thank you - Ray
 

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Hi Ray & welcome to MRF.

.75mm would be good - 1.0mm even better.

Rather than use "household" cable I would suggest that you obtain a couple of coils of single flexible from a source such as Maplins or CPC.

It would also be much better to run a separate "bus" for the accessories.

Hope this helps.
 

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In the short term you could just try connecting DCC to your existing wiring.

If your existing wiring allows it then switch all sections to the same controller and replace that controller with the DCC command station. If not then remove all controllers, join together the wires that used to connect the layout to the controllers (check correct polarity) and connect these to the command station. Turn on all isolating sections, remove all non-DCC locomotives and switch on! Then it is worth short-circuiting each track section in turn by putting a coin on the rails, and making sure that the command station immediately cuts out each time.

Although some of the wires may be thinner than a DCC bus, each one will only be carrying the current for one train so it shouldn't be a problem. In fact it's probably work sticking with this arrangement until you've decided that you definitely want to go for DCC - and maybe even after that. While a new layout will probably need less wiring if DCC is used, changing all your existing wiring is a big job and may not be necessary.
 

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Hi Rayl and welcome to the MRF.

The general consensus here on the MRF re. DCC wire sizes would seem to be as follows:-

Main DCC Bus - 32 x 0.2mm wired as a radial bus from the controller/power source.

Droppers from track to DCC Bus - Over 300 mm distance - 16 x 0.2mm
Less than 300mm distance - 7 x 0.2mm is adequate.

If you are planning electromagnets for auto-uncoupling the wiring should, as a minimum, be 16 x 0.2mm.

Hope this helps.
 

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Discussion Starter · #5 ·
Thank you for the guidance to date, but why is it such matters are not explained with the instruction books?

Thank you also for the welcome, much appreciated - I am sure MRF is going to be most useful.
 

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Discussion Starter · #7 ·
The advice offered gave me confidence to have a concerted effort to get digital started. I used the advice of disconnecting the existing DC supply, and connected DCC to the down line, and to my delight achieved independent movement of three locos.

Only having three locos with decoders I reconnected DC to the up line, and was able to run the non decoder locos. So my circuit is now operational and utilising dcc in a small way.

Satisfied with that progress I am going to install three pairs of bus, 2 for power to the main tracks, 2 for points motors, and two for other accessories in the future. I have chosen to go with 32/0.2 which I will purchase from Maplin. I soldered my existing droppers to the bottom of the rails before ballasting a year or two ago. The droppers are 16/0.2 and these will be connected to the 32/0.2 power supply to the main track. After re-checking polarity I will solder the wire joints as I am not likely to ever change the layout.

In the end I ignored all details about CV's. I simply changed the name a number on the controller. I am sure there is much more I could do to improve the running, but I am not in any particular rush. Thank you MRF for this push in the right direction. Whats next?
 

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QUOTE (RayL @ 24 Dec 2008, 16:23) <{POST_SNAPBACK}>The advice offered gave me confidence to have a concerted effort to get digital started. I used the advice of disconnecting the existing DC supply, and connected DCC to the down line, and to my delight achieved independent movement of three locos.

Only having three locos with decoders I reconnected DC to the up line, and was able to run the non decoder locos. So my circuit is now operational and utilising dcc in a small way.

Satisfied with that progress I am going to install three pairs of bus, 2 for power to the main tracks, 2 for points motors, and two for other accessories in the future. I have chosen to go with 32/0.2 which I will purchase from Maplin. I soldered my existing droppers to the bottom of the rails before ballasting a year or two ago. The droppers are 16/0.2 and these will be connected to the 32/0.2 power supply to the main track. After re-checking polarity I will solder the wire joints as I am not likely to ever change the layout.

In the end I ignored all details about CV's. I simply changed the name a number on the controller. I am sure there is much more I could do to improve the running, but I am not in any particular rush. Thank you MRF for this push in the right direction. Whats next?

Whats next?

Sound!
 

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QUOTE Whats next?

Sound!

It has to be.

I am off to Howes near Oxford in the new year to have a chat - and probably take my WC (City of Wells for those of you with other thoughts!)
to see what they can do for me and it.

Glad DCC is working out for you.
 

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QUOTE (barrymx5 @ 24 Dec 2008, 16:40) <{POST_SNAPBACK}>It has to be.

I am off to Howes near Oxford in the new year to have a chat - and probably take my WC (City of Wells for those of you with other thoughts!)
to see what they can do for me and it.

Glad DCC is working out for you.

They have done a nice job on the Spam can, I am sure you will be happy.
 

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QUOTE (RayL @ 24 Dec 2008, 16:23) <{POST_SNAPBACK}>Whats next?

Whilst you still have the chance.

Why not slip a simple DPDT rocker switch into your circuit to make the layout DCC/DC switchable? In this way you are able to run those loco's not yet fitted with chips or those DC locos you feel are impractical to fit with them.

Mike
 

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Discussion Starter · #13 ·
Mike - Can you please explain the DPDT rocker switch to enable both DCC or DC running, at this stage I guess I can still incorporate anything.
 

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QUOTE (RayL @ 26 Dec 2008, 09:48) <{POST_SNAPBACK}>Mike - Can you please explain the DPDT rocker switch to enable both DCC or DC running, at this stage I guess I can still incorporate anything.

Sure.

At this stage, as I understand it, you have;-
a] A dc controller
b] A dcc controller
c] A power bus wired to your layout.

What you need to do is insert a DPDT rocker switch connecting the two controllers to the power bus. Something like this from Maplin will do. (cost about £1.70.)



You connect both controllers to the switch using the end terminals - dc to one end, dcc to the other, like this.



The centre terminals are connected directly to your power bus. The only thing you have to ensure is that you have positive down one side of the switch and negative down the other.

By including a switch like this, depressing the switch will change the power running to the rails to either dc operation or dcc and gives you the best of both worlds as you can run what you want, when you want.

Word of warning though. Make sure none of your dc engines are on the live track when switching to dcc or they will start singing (sometimes accompanied by vibration) and you may eventually burn the motors out. The singing is caused by the dc motors receiving an alternating current and the poor old motors don't know whether to go forwards or backwards - so they sing and shake as a way of complaining. Maybe an idea to have all dc engines stabled on isolated sections when running dcc - could be 'on shed' etc.

Hope this helps.

Mike
 

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That's pretty well what I have done for my main lines.


One other thing though: when on DC, make sure that all other locomotives / trains are isolated, otherwise you'll get a mass take off of trains as you increase the power! (Been there, done that!)
 

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Discussion Starter · #16 ·
Once again more useful information. Thank you. I also took the opportunity to look at Hawkers Bridge - a facinating tale, and a layout to envy.

Good point about isolating the locos before switching over. So much to take in. Thank you again.
 

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Discussion Starter · #17 ·
With the knowledge the forum has shared with me I have installed the BUS and connected all the droppers using a variety of connections as I carefully checked the polarity using one of my original Hornby DC controllers. Each time it shorted out, I switched it off to reset, then tried again, a relatively simple exercise. I then tried running one DC locomotive to test it all ran correctly. Total success.

I then connected the DCC controller and within minutes was able to run simultaneously three locomotives. Flushed with success I took my other locomotives to my local dealer to have decoders fitted. His view is that sound decoders are still expensive, and not realistic and it is better to wait a little longer. Unfortunatley my skills are not developed enough to fit decoders myself. I will prcatice my soldering ability as I finalise the connections to the BUS.

Whilst at the dealers we discussed the turnouts. Mine are all standard Hornby, and at present I have six with motors. I took the dealers advice to keep the Hornby point motors, and purchased a Lenz decoder. That is my next project, and will be run from the seperate BUS installled for that purpose.

I beleive it is important to listen to the advice of ones local dealer as he will be the guy who will be sorting out the problems should it all go wrong. Before I start the installation has the forum any tips before I proceed?


My thought for pursuing this very simplistic thread is I beleive there are other novice modellers who have modest ambitions, limited time and budgets, and would also benefit from the basic information I seek. Thank you to the forum, for the help, and keeping it simple.
 
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