How do I go about using DCC for points? I assume that if I have a DCC layout I don't need to have a control panel with switches but use a decoder for points then control these from the DCC controller via the bus. But would a decoder for set of points work out very expensive?
You use an accessories decoder, the ones I've seen had four, six or eight outputs. You should have a separate controller (or pushbuttons in strategic locations) for the turnouts and signals etc. It's easier to operate that way, unless you like pushing odd button combinations on your handheld controller.
There's software available that lets you play at central traffic controller or signal box operator. You can set up interlocking, define routes through junctions, and so on. I don't know the status of this software, as I last saw it in operation about two years ago, and haven't seen it since. Worked nicely on my friend's layout, though. (He's since moved, so the layout is gone.)
BTW, if you use the decoder to power the turnout motor, the latter must not be the solenoid type, as these can draw surprisingly high momentary currents. The recommended motor is a DC motor that turns gears till they hit a limit, which may or may not turn off power to the motor. My friend used low current motors that were left on at all times on some turnouts, and low current relays to trip the solenoid turnout solenoids on others.
Yes they are but the address range is different from the loco address range. I used the DAC10 from
when setting up my fiddle yard can drive 8 sets of points and these can be either single or double ended. Has a CDU built in and has 10 inputs. I have programmed the inputs to set up routes so that pressing a button on a panel will cause all the points for that particular route to be set, in CDU operation you can each point switching sequentially as the unit waits for the CDU to recharge. It also has separate LED output lines to show the last position commanded to for each set of points. Lots of CVs to tweak things. The points can still be set manually with address for a particular set of points.
Of course this is one of the more complicated units but more basic ones are also available.
Currently I'm using the MERG accessory decoders and an encoder controlled by switches. However you can also use computer control for route setting etc.
The MERG ones come in blocks of four. For solenoid points there is a CDU version, for motor points there is a steady state decoder. I have a mix and both work well, if the steady state version isn't controlling motors instead of appearing as 1x4 points it can be made to appear as 2x4 on/off controls for lights.
has some more details. Although you'll need to be a member to buy the kits.
There are also other options such as not going down the DCC route for layout control (e.g. Gordon Hopkins RPC) It is very much upto you.
DCC wiring for points can be a lot simpler than traditional methods (particularly if you go with computer control) but to be honest I'm not convinced if you never want computer control. (There are separate advantages for modular layouts)
 Actually I've still got rather a lot of wiring to do before the end of the month when I'm showing it at colchester.
Just don't tell that to the many people who *do* use solenods ;-)
The answer is to use a CDU to smooth out the current pulses. Many (most) commercial accessory decoders have the facility for an external power connection and only use the DCC connection to receive commands.
We were tempted to use DCC for the points on Farnborough Road. Decided against it, with the deciding factor being the risk of shorting out the DCC on an exhibition layout and having to re-programme the whole shebang in front of the paying public.
I like the encoder idea. I had a quick look at the small US switching layout at Manchester Ex (sorry can't remember the name). It had a conventional looking mimic diagram with the encoder built in the panel. It would certainly simplify the panel to board wiring, particularly with a multi-baseboard layout. From my limited use of DCC with points via accesory decoders, it looks a slow way to select and switch points, especially when used on an exhibition layout, when you want to keep things moving. I suppose the eventual aim is to go down the PC "signalbox" route as the boys from the Wirral club have done.
I spent some time watching Wirral (layout) at the scalefour forum (Wells) a few weeks ago. The layout is DCC Digitrax and the turnouts were being run using Railroad and Co from a laptop in front of the layout. It seemed to take an age to set routes, and turnouts. There was a lack of activity on the layout. I understand the advantages of route setting, but in the past I've settled for mimic panels to control turnouts, as I would prefer to watch my stock running rather than squinting at a laptop screen. I might use stationary decoders for a fiddleyard, but I'm not totally convinced that additional cost justifies the entire layout ?.
I notice that someone else on this newsgroup has noticed one of the problems with DCC control which is if you get a problem due to a short you can lose layout control.
The MERG approach uses a separate DCC & Power structure to control the point decoders so that problem goes away. For my modular layout I've used PowerPak / PowerPole connectors from Torberry
and 8 way speaker cable to connect the modules together. The speaker cable is 8x2.5mm Sommer Elephant cable used for pro-audio and the connectors are good for 30 Amps with a lifecycle of 10000 connections.
That gives me 2xTrack DCC, 2xAccessory Power and 2xAccessory DCC control plus two connectors for spares.