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[geoff]

 

I was also reading about all the complictions with points!

 

Seems to me that there is not a set of points on the market that will work without problems on a DCC system unless one is prepared (or able) to make extensive alterations to the set of points.

 

Chris

 

Chris, the points will work on DC and DCC, the difference is that issues which folk seem to ignore or accept as normal on DC, locos hesitating on points or stopping and needing a nudge, are accentuated on DCC because the electrical protection circuits are much more precise in their operation and shut down the system for the slightest short circuit. They need to because of the higher power output of most DCC systems which would cause more damage than would occur on a DC system. The main cause of the problem seems to stem from the way many points are made in regard to their electrical connections. For example Peco points often are arranged so that the blades switch the polarity at the frog and this can mean that the blades are connected together so that the open blade will be at the opposite polarity to the adjacent running rail. In this situation if the back of a metal wheel passing through the gap touches the blade there will be a short circuit. On DC this may cause the train to hesitate but its momentum, unless running slowly, will usually carry it through and clear the blade. On a DCC system this will almost always cause an immediate shutdown of the track power which will continue until the short circuit is removed by nudging the train along. This situation can also arise at the frog of points with insulated frogs when wheels can bridge the insulation and make contact with both rails just beyond the plastic nose of the crossing. 

 

Rewiring Peco points is quite simple if you are adept at soldering and I would advise it for DC as well as DCC. It will mean that some switching arrangement for the polarity of the frog will have to be arranged. All this is addressed I believe in the data sheet which comes with Peco points as well as on many sites on the web.

 

Many of the practices advised for DCC are also good and desirable for reliable operation on DC.

 

I hope this helps clear up this often misunderstood issue. Electricity on a model railway need not be complicated and in the main what goes for DC also goes for DCC. 

 

Geoff

[model-trains]

You say 'Go play with a DCC sytem'! Where?

 

I cant afford to fork out hundreds of pounds on a DCC control system on the off chance that it might work for me!!

 

I was also reading about all the complictions with points!

 

Seems to me that there is not a set of points on the market that will work without problems on a DCC system unless one is prepared (or able) to make extensive alterations to the set of points.

 

Chris

[model-trains]

You say 'Go play with a DCC sytem'! Where?

 

I cant afford to fork out hundreds of pounds on a DCC control system on the off chance that it might work for me!!

 

I was also reading about all the complictions with points!

 

Seems to me that there is not a set of points on the market that will work without problems on a DCC system unless one is prepared (or able) to make extensive alterations to the set of points.

 

Chris

Hi Chris, I have just come back to model trains after 10's of years. ;-)

 

I went straight into dcc and do not regret it, dcc offers more and more control with lots more to come that's certain.

 

When I started I didn't know what a dcc bus was and quite afew other terms but isn't that true in anything new. The forums are here to help anc thdre are some good guys to help you.

 

Before you start wuith dcc ask yourself a few basic questions.

 

Do you want to control from a computer or laptop. If yes go dcc

 

Do you want to run numerous loco's at the same time. If yes go dcc

 

Do you want lights and sound, etc, etc.

 

DCC offers so much and there is lots more coming, itis the best thing I ever did and that was only e months ago.

 

With DCC you need a dcc bus, it is easy, it is similar to running a couple of spurs of lighting cable under your base board from your controller. I use Hornby elink and software RailMaster.

 

Next may seem a lot but it doesn't take long and is important. You need to drop +/- wires from yiur track to thd dcc bus. It is suggested that you do every piece of track as fishplates can cause voltage drops, I did every other. Why so many connections? Because your dcc bus carries power to locos and signals to decoders, etc.

 

There may appear a lot of wires in dcc but there are less in the end than you would have with dcc and you don't have point switches, they are controlled at theclick of a mouse button.

 

Is dcc more expensive? Yes and no. Some things maybe are, some maybe not. You do however have a cost for decoders, these do the work for you. Are they expensive, like anything pick and choose whst is best for you. You can get a card of 8 point motor decoders for around £40. I feel this is a small price to pay for the control you get. Chips in locos are not cheap but again be selective what you buy, prices are coming down so just be selective in what you buy.

 

Check the forum, see how many people say dcc is the best thing they did. Then ask is it right for you, Good luck whatever you decide.

[model-trains]

There may appear a lot of wires in dcc but there are less in the end than you would have with dcc and you don't have point switches, they are controlled at theclick of a mouse button.

 

 

The above should read...

 

There may appear a lot of wires in DCC but there are less in the end than you would have with DC and you don't have point switches, they are controlled at the click of a mouse button.

[model-trains]

Let me rectify a few urban myths surrounding DCC as perpetuated above:

 

1) you do not need to control your layout with a PC if you go DCC. DCC is perfectly fine if you use the traditional panel for point/route control. Just disconnect* any DC control switches if you convert an existing layout to DCC.

 

2) DCC needs the same amount of wiring, to the same standard as any DC layout would. It's only wired slightly differently. This is especially true if one wishes to implement PC control.

 

3) DCC does not require power routing of the point frogs, that requirement is given by the type of stock you use: 4- and to an extent 6-wheel loco's need power from the frog if they'd need to transverse Electrofrog (or similar) points.

 

4) DCC does not require a track bus. It's easier for long, elongated and modular layouts, but smaller ones will work just as well with a star-type wiring.

 

5) DCC is more expensive then DC, but it pays back in other areas, like ease of wiring (on non-PC controlled layouts), easier operations, improved running qualities, additional on-board functions (interior lighting, remote uncouplers, etc) and less frequent track cleaning.

 

6) DCC will work perfectly fine on small layouts with a single loco or small fleet. In fact, the maximum number of loco's is limited by the command station and/or hand-held controller. Most DCC systems now support 99 or 9999 addresses.

 

*actually, you can leave them in place, just switch them ON permanently. However, any integrated DC controllers on the panel must be disconnected!

 

Thank you for your comments Dutch_Master

 

Although I agree with many items stated above I cannot agree totally with all of them because as with everything there are swings and roundabouts.

 

1) although you do not have to run DCC from a computer I believe, and many others, it is much easier from a computer and a layout is less cluttered.

 

2) DCC needs the same amount of wiring as DC. If DCC is run without a computer that may be the case but, if run from a computer there has to be less wiring. Points and decoders are wired to each other and the DCC Bus in close proximity in most cases. With a computer you do not have extra wiring for points and signal switches back to the point of the controller it is all done through the DCC Bus.

 

4) Although you can manage without a DCC Bus to run the smallest of layouts as soon as you start running multiple loco's with sound and lights and have other accessories drawing power from it also you will soon wish you had installed a DCC Bus. I am aware of people who have started off not installing a DCC bus, they have run multiple loops from one power connector but as their layout and loco stock increased and after adding additional accessories they wished they had installed the bus.

 

The bus gives even distribution of power to all areas of the track which has to be good not just for the loco's and resources, if a point or fish plate became less efficient the power to the track can be less efficient.

 

5) DCC is definitely more expensive but it depends how much you want to get into it. But prices are coming down and by shopping around money can be saved it doesn't have to cost a fortune but it can if you want everything. If budget is an issue these people will probably only purchase a couple of loco's and once they have them that's it. A lot of cost can be incurred in points and accessories but it is up to the individual how many they want but, they will want points, point motors and decoders. By shopping around you can get good value quality decoders and the ADS-8 example I gave previously is a good price for 8 point motors. £5 per point is a small price for the control you have and they are so easy to set up. DC Concepts also do 4's and smaller cards you don't have to buy an 8 unless you have at least 8 points/point motors.

 

6) I agree with your comments that the number of loco's is set by the controller but supply of power to the track is another. Many train sets with DCC have a 1amp transformer when purchased and it is not often before users find they have to upgrade to a 4amp.

 

Just to come back to the DCC Bus, depending on what you want to run and control yes, you can get away without the DCC Bus but for me, even distribution of power to the track and the piece of mind (call it my insurance policy) I feel happier by adding the DCC Bus and knowing if a point or fish-plate becomes less efficient it will continue to receive power from the track one side or the other and I can continue to add signals, lighting, etc, etc, etc.

 

Other peoples comments on this subject are welcome.