My currently under construction N scale layout is the first layout I've built that is using Peco turnouts, all others have used Atlas in the past. I love the power routing feature of these turnouts, but this brings up a question to anyone who's a veteran with these and block wiring.
Do you still typically use insulators on your spurs/siding and control power with a toggle switch or do you rely completely on the power routing features of these turnouts.
As part of my future plan to migrate this layout to DCC in a year or so, my plan was to put feeders on each spur, but this of course will provide continuous power to the section of track even if the turnout is not thrown for it, unless I use a toggle switch.
My layout is not huge, only 8x8 but I still want to ensure max power to all areas, hence the feeders even pre-DCC. Is this how everyone else wires their layout?
Modeling the fictional B&M Dowe, NH branch in the early 50's.
DCC is less complex than block based DC and requires less wiring and switching (although some people are feeder fanatics); usually the only problem is reversing loops.
Turnout machines with SPDT or DPDT switches can route power to the spurs for you. I don't believe that stationary DCC decoders will route power other than to the frog.
In case you haven't seen it, Allan Gartner's Wiring for DCC web site is a great place to start.
Alan
Co-owner of the proposed CT River Valley RR (HO scale) http://home.comcast.net/~docinct/CTRiverValleyRR/
Welcome to the wonderful world of electrofrogs. It's one that I know well.
First, a differentiation:
Short spurs don't need a gap in the rail leading from the frog to the bumper. If no locomotive will ever move on that spur unless the turnout is positioned for it, throwing the points to the alternate route will kill it. You can park a loco there, secure in the knowledge that, with both rails at the same potential, it won't be going anywhere.
(A DCC loco will lose lights - no big deal - and sound if the track is electrically neutral.)
Sidings need, at a minimum, gaps somewhere between the frogs on both tracks. Since the usual DC practice is to gap both ends of both siding and through track (which then become two separate blocks) the only "extra" gaps are those which isolate the DC common rail between the frogs on the siding. Those gaps are also necessary to isolate that rail for DCC.
Place the gaps closer to the frog than the clearance point for that turnout, and never, ever, run past the clearance point unless the route you will use has been selected and the points are properly aligned.
A note about that clearance point - on a both (or all three) tracks curved turnout, it may be quite a way down the road from the frog. I have some which are fully 500mm from frog to clearance point.
Chuck (Modeling Central Japan in September, 1964 - analog DC, hand-laid specialwork)
Cannoli My currently under construction N scale layout is the first layout I've built that is using Peco turnouts, all others have used Atlas in the past. I love the power routing feature of these turnouts, but this brings up a question to anyone who's a veteran with these and block wiring.
Let's separate the gaps required for turnout wiring, and those put in for block wiring for the present. Gaps/insulated rail joiners can be used for both purposes at the same time, but to understand what is going on, we'll start with just the turnout wiring for a power routing turnout. Note that the turnout wiring applies to both DC and DCC.
See http://www.proto87.com/turnout-wiring-for-DCC.html for some excellent animated diagrams of your situation - Diagram 4 applies.
Because a power routing turnout has it's frog change polarity when the turnout is thrown, power cannot be fed into the frog from the frog end of the turnout. So any place there's a feeder or a turnout capable of routing power into any path of the frog end of the turnout, that frog rail must have a gap somewhere between the frog and the source of power (feeder or another turnout). If the path from the frog of the turnout ends in a dead-end spur, and there is no feeder on the spur, then no gap is needed.
But as you point out, if you put a bus feeder on the frog rail of a dead end spur, you need a gap between the feeder and the frog.
Do you still typically use insulators on your spurs/siding and control power with a toggle switch or do you rely completely on the power routing features of these turnouts. As part of my future plan to migrate this layout to DCC in a year or so, my plan was to put feeders on each spur, but this of course will provide continuous power to the section of track even if the turnout is not thrown for it, unless I use a toggle switch.
Whether I use power routing or add a toggle switch to control spurs and sidings depends on the operational need. If an engine is not going to be moving on the spur or siding when the turnout is thrown against it - many to most cases - there is no need for a separate DC block and toggle wiring. If additional power feeds in a power-routed spur or siding are needed I run "jumper" feeders from the controlling turnout. These jumper feeders tie to the turnout stock rail feeders at their power bus tie for the extended stock rails, and to the frog feeder at the frog contact for the extended frog rail. The jumper feeders provide more reliable power down the siding or spur by bypassing the metal rail joiners.
If an engine is likely to be moving on a spur or siding while the turnout is thrown against it, then I gap the extended frog rail at the clearance point, and wire in the block toggle.
From an operational view in DCC, you may or may not want those power routed sections to be always live. Keeping the power routed sections always live means you can access the locomotive at any time without having to throw the turnout for the locomotive. You can play with the lights and/or sounds while the locomotive is sitting still. OTOH, being able to kill a DCC locomotive by throwing the turnout against it has its advantages. You can't accidentally select the locomotive and run it into a turnout set against it, causing the layout to short and shut down (or collide with something else). Sounds don't mysteriously start up when the locomotive is sitting on a dead section.
I find rail joiners to be unreliable conductors of power over time, so I end up adding feeders sooner or later to the flex track and commerical turnouts. In the past, I didn't use rail joiners at all with my handlaid track, so feeders had to be provided for every length of rail from the beginning. This is not as onerous as it sounds because I would solder an 18" piece of 26 gauge magnet wire to each rail piece before spiking it down.
For my handlaid turnouts, I used the switched frog wiring method (Diagram 7) with the frog powered by an electrical contact on the turnout throw mechanism.
I use common rail for my DC. I run a 16 gauge bare copper braided (antenna) wire common rail bus in a loop under the layout. Common rail feeders are soldered to this bus. Since my layout is small enough to only justify a single booster in DCC, common rail presents no issues to later conversion.
I typically used a Radio Shark screw barrier terminal block with a bus bar linking all or half the screws on the terminal block as a distribution point for the feeders for the switched rail within a DC block. One terminal block would also be attached to the frog feed point of the frog contact to distribute power to the extended frog rail(s) in a power routed section.
Final point - my wire gauges are lighter than what is often recommended for DCC. My layouts are small. Since I never double-head, my normal load is always a 1/2 amp or less (HO and HOn3). My DC power supplies are rated for 1.5 amps or less. And having a feeder, even though it's only 26 gauge, for nearly every section of rail means there are lots of parallel paths to spread the current. In my case, going to heavier wire is not needed. If I were to get one of the more powerful DCC systems, I would have to limit the current by an external breaker/limiter to the 1.5-2.0 amps the wiring will comfortably and safely support.
my thoughts and experiences, your choices
Fred W