After 8 months of framing and track laying (mostly weekends), I hooked up the track leads to the bus and connected a second-hand MRC DC power pack just to see a locomotive move. There are approximately 360 feet of code 83 track divided temporarily into 5 power districts for eventual conversion to DCC. There is at least one set of drops per district connected into the bus via suit case connectors. The drops and bus are now 20 gauge but I will be changing the bus to 16 or 18.
One mainline district has 2 DCC-friendly Walthers turnouts and another has a 5-track staging yard with 10 turnouts (a combination of new DCC-friendly code 83 and older Shinohara code 100). None of the turnouts are isolated electrically from the other tracks.
After connecting the feeds to the bus, and for convenience, I ran 2 leads from the bus to the MRC via suit case connectors. The MRC powered up but even at full throttle, nothing, nada, nyet, nix, zero. Not even a hum - tried an Athearn DC Genesis, an Athearn late run SD-40-2 RTR, and even a 20 plus year old Athearn blue box unit.
I then moved the MRC to a stub-ended power district and direct connected to the track via leads soldered to track joiners. At 100% throttle, the late run Athearn RTR and the older blue box unit buzzed but did creep along (not at the same time) and eventually tripped the overload circuit.
Is my problem huge or merely enormous? Should I consider battery powered trains or RC planes?
Do you have any reverse loops? Or you may have a feeder or two hooked up backwards. If you have a multimeter, set it to ohms and hook it to the bus with no locos (or tools - it's easy to leave a hammer ot screwdriver shorting the rails!) on the track - it should show infinite (open circuit). If it shows low resistence - well, you've got a short somewhere. I think the reason you got the buzz and slight movement when connected to the far end is that it was far enough away from the short that the #20 wire did not allow enough current flow to initially trip the breaker int he power pack. I'd say the issue is closer to where you first hooked it up. I also doubt you will get satifactory operation with long runs of #20 wire, even on a temporary basis, even without any other wiring problems. Your locos will slow dramatically at the farthest distance from the power pack, even using DC.
As for turnouts, those with live frogs generally need insulated joiners on the frog side. Any power feeders to the siding need to be beyond the gaps. If you feed power directly into a live frog turnout you'll get a short since the two rails that come together at the frog point touch with no insulation in such a turnout, and if the track is wired correctly these are opposite terminals.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for the reply.
No reverse loops. In essence, the track configuration is a folded loop yielding two mainlines. Even the staging yard has an eastbound side and a westbound side. No crossovers, etc. (see www.duckdogger.us in the modeling section for photos).
Lastly, I may have connected the feeders to the bus incorrectly. There should be, for lack of better wording, a bus for the eastbound track and a bus for the westbound track? I connected everything on to one bus.
One bus is fine, but you have to take care that all the feeders hook the proper bus wire to the proper rail. If you used, say red and white wires for the bus, if you put a loco on the track and run it around the loop, the engineer's side should always be the red wire. From underneath it can get confusing, if there are two parallel tracks that are opposite sides of the same oval, you woudl want to wire them up red-white-red-white but that would be wrong - they need to be white-red-red-white (counting the rails from the front of the table to the back). A cheap way to keep track while underneath the layout is to get a buzzer and battery from radio shack and hook it up to the bus wires: bus wire---buzzer---battery----bus wire That way, if you create a short, the buzzer will sound. So long as you connect the feeders properly, the buzzer will remain quiet.
For the bus on any layout I make I use solid core household wire which can stand the amperage (or higher) of the system I am using.
E.G. 3 amp system 5 amp Bus wire
5 amp system 10 amp Bus wire.
I leave the sheath on the wire and just open upwhere I need to fix droppers by soldering.
ukrailroader
I routinely gap at least one end of a segment between any two turnouts. I also feed the segment between turnouts just to be sure that it gets power. I also wire and power each new section to make sure I have not either forgotten something or missed a potential conflict. I run an engine to make sure my power distribution works. Nothing like erecting an entire track system, then wiring it all, then finding that "something" isn't right.
Bus wire is at the least a robust speaker wire, something capable of handling 5-8 amps for a length of 30'.
I also bare the bus where it makes the most sense to place a feeder up through the benchwork, and I solder all connections after wrapping the feeder wire, 20 gauge, around the bared bus wire.
Had you hooked up a DCC system, a simple quarter test would soon show if you have any shorts, assuming your track surfaces are clean and that you have properly connected the tracks and wiring, and that the wiring meets the minimum standards for power transmission.
-Crandell
Thanks for your time in responding. This was a lot simpler 30 plus years ago when I had nothing but and oval of code 100 flex on a spare bedroom floor. But then again, cooler technology didn't keep beer very cold in '72 either.
My only non-DCC friendly turnouts are in the staging yards so if I insulate the turnouts' diverging stub from the next section of track that should preclude a short in that area (presuming all the feeders have been connected to the proper bus wire)?
Can it be as simple as sawing throught the rail joiners (guesing both rails need to be insolated) and inserting a piece of electrically inert material to maintain the gap? I had left narrow gaps between the rail junctions due to heat expansion. As soon as the shade hits that side of the house, I'll be about it.
duckdoggerAfter connecting the feeds to the bus,
But I am guessing the problem is going to be in the older Shinohara turnouts. They have hot frogs. So a set of feeders on either of the exiting tracks without a gap on either of the frog rails will cause a short circuit. If it is double ended yard tracks the feeder(s) could be way back beyond the points of the other turnouts.
Okay, I have removed my older turnouts and installed dcc friendly turnouts. Ripped out the old undersized bus and track leads and upgraded to 18 gauge feeding the track and a 14 gauge bus. So far, testing reveals no shorts.
Aside from simplfied short tracking/correcting, why would I want to have a sub bus for each power district? And lastly, are the 1156 bulbs wired in series or parallel - which I guess means to just one of the bus wires or across both? I look at schematics and may as well be trying to read Hebrew, or stenographer's shorthand.
Oh yeah. Now that I have almost 200 feet of the mailine wired, the litlle ole MRC dc power pack won't push enough power to let the test loco move beyond a crawl. Anyway to piggyback another dc for testing? Not ready to buy the DCC yet - being no longer employed and all as the Orange box closed our store and did not have any openings for transferring to another store......
That should serve you well.
Aside from simplfied short tracking/correcting, why would I want to have a sub bus for each power district?
If you use the light bulbs, with this configuration, a short on one sub-bus won't take down the whole railroad.
And lastly, are the 1156 bulbs wired in series or parallel - which I guess means to just one of the bus wires or across both? I look at schematics and may as well be trying to read Hebrew, or stenographer's shorthand.
The bulbs are in series. That way they limit the current in the event of a short.
Running one loco, with a 14 gauge bus, shouldn't be a problem. Make sure the track and the wheels are clean!
Jeff But it's a dry heat!
duckdogger Okay, I have removed my older turnouts and installed dcc friendly turnouts. Ripped out the old undersized bus and track leads and upgraded to 18 gauge feeding the track and a 14 gauge bus. So far, testing reveals no shorts. Aside from simplfied short tracking/correcting, why would I want to have a sub bus for each power district? And lastly, are the 1156 bulbs wired in series or parallel - which I guess means to just one of the bus wires or across both? I look at schematics and may as well be trying to read Hebrew, or stenographer's shorthand. Oh yeah. Now that I have almost 200 feet of the mailine wired, the litlle ole MRC dc power pack won't push enough power to let the test loco move beyond a crawl. Anyway to piggyback another dc for testing? Not ready to buy the DCC yet - being no longer employed and all as the Orange box closed our store and did not have any openings for transferring to another store......
If you have 14 gauge wire and 18 gauge feeder drops at regualr intervals, the DC pack should not have any trouble runnign a loco anywhere on the layout. Is the track where the loco slows to a crawl actually powered from this bus and the feeders, or is it a section past a pwoer-routing turnout that is relying on the turnout makign contact to provide the power? With plenty of feeders and a good bus line, a 9 volt battery should run a suitably low-powered loco (Stewart Baldwin switchers with the Canon motros, for example), a 1-2 amp DC power pack should run pretty much any DC loco anywhere with no problems. If it doesn;t run with DC, it won't be much if any better with DCC.
Thanks for the input. All the sections I have tested are powered by the bus. I noticed that in one instance, the loco was fine and minutes later on the same section, it was not. Maybe some of the feeders are not tight enough in their attachment to the bus? I had been merely wrapping the stranded feeders around the solid bus till I was sure the section was okay, and then soldering the junction. Maybe some loose-ness to be dealt with.
It should be easier to pinpoint as I am now breaking the main bus into sections to function as sub bus. I bought more 14 gauge wire (different color combo) to be the main bus.
I am embarassed to ask, but is wiring the light bulb "in series" mean it is wired to one bus line only or does it connect to both bus wires? And if one only, does that mean the bus is broken and the ends spanned by the wires for the bulb?
I am really struggling with this. I understand the application to a closed loop circuit but the bus is not a closed loop.
duckdogger is wiring the light bulb "in series" mean it is wired to one bus line only or does it connect to both bus wires? And if one only, does that mean the bus is broken and the ends spanned by the wires for the bulb?
is wiring the light bulb "in series" mean it is wired to one bus line only or does it connect to both bus wires? And if one only, does that mean the bus is broken and the ends spanned by the wires for the bulb?
That's exactly what "in series" means. Connect the bulb as you described in one of the bus wires.
duckdogger I am embarassed to ask, but is wiring the light bulb "in series" mean it is wired to one bus line only or does it connect to both bus wires? And if one only, does that mean the bus is broken and the ends spanned by the wires for the bulb? I am really struggling with this. I understand the application to a closed loop circuit but the bus is not a closed loop.
Ah but see the bus IS a closed loop - when a loco is on the track! Power out one bus wire, to the feeder, to the rail, to the loco, to the other rail, to the feeder, to the bus, back to the power supply. If the bus is a closed loop with nothing on the track, you have a problem - a short circuit. Or a metal tool on the track (foudn all your Kadee coupler gauges?).
The easiest place to go wrong is to mess up ONE feeder pair. Say at every location you have the red bus wire hooked to feeders going to the right rail, except one you get twisted up by mistake and connect the feeder from the right rail to the white bus wire instead. You've now created a short which will prevent things from running. In the case of one reversed feeder in a room-size layout, you just might experience the problem you're having, where it's not enough of a short to trip the circuit breaker in your DC power pack, but it puts such a load on it, any loco runs slowly. Usually such a short is pretty solid and nothign will even creep, and the circuit breaker will trip, but what I described is possible and can be a real pain to find.
As for the light bulb, you cut ONE of the bus wires and span the cut ends witht he bulb. That's series wiring. If you connect one side of the bulb to one bus wire and one side to the other, that's parallel (with the track and with the power supply), and would not accomplish the purpose here
Again, thanks for helping me maintain a grip on my sanity. I am so close the the DCC wiring abyss.
Now I understand the bulb thing. It was making no sense to me.
I think you are dead nuts on about the reversed feeder scenario. What will ultimately be two of the five power districts are now running fine as I isolated them from the other two I had wired with feeders. Tomorrow before the Sun is on high broil here in Phoenix, I will be under the upper level looking for wrong color wire going to the bus.
And if I soldered the wrong color feeder to the rail, I'm buying some spray paint and changing the color after I revise the bus connection.
Colored flags and tape work well, but what I did was play it smart. In the less-than-well lit undersides of the layout, red and black look much alike - so I used red and white wire for my bus. I also found smaller gauge red and white wire to use a feeders. Now, I still could have messed up up top by soldering a feeder to the wrong side, but at least underenath it was super simple - red to red, white to white.
Thats what I had done, red to red, white to white. I crawled under the entire layout this morning and did not find any mis-matched wires but I did find several that we loose. Undid the solder, reattached and ran a loco up and around. Even by just touching the power wires to the track by hand, everything was fine.
Appreciate everyone's help and suggestions. It's tiresome enough to do all the work, and as this is an outdoor layout, in the Sun, and then have it not function properly is enough to put me of doughnuts.
BTW, I overcame the solar heat gain issues I referenced in another thread by using a top layer of extruded foam with 1 inch spacers to provide shade and an air layer buffer to block convection. Water filled ice tea jugs (AZ Green Tea) hold them down even in the winds we have been having. Now the track stays cool as the air temperature during the direct Sun hours.
I just finished installing the last of the DCC friendly Walthers turnouts in a double ended yard. Everything I have read here and at sites such as Allan Gartners, indicates turnouts with isolated frogs do not require any gapping on the diverging rails so I didn't (and I already had a set in the track plan without problems). I added feeders before and after the turnouts in addition to others within the yard tracks. None of the new feeders have been connected to the bus.
I have a short. I still have 3 Atlas turnouts that are not DCC freindly off the main line but they do not connect to anything. They will be replaced before track is installed to their diverging rails. Are they the problem? I don't recall if the are power routing but could see a problem if they were and were set for the siding.
I am crawling under the layout to insure no drops got mis-connected since the last time I ran loco without problems on Sunday but at first glance it looks as though the color match is correct. Any ideas?
Which Atlas turnouts? This whole 'DCC friendly' thing is blown way out of proportion. If your wheel backs touch the open switch point when going through the turnout - your wheels are out of gauge, it's not that the turnout isn't 'dcc friendly'. The only Atlas turnouts made anytime in the recent past that are power routing are the ones that are actually made by Roco - the motorized ones even have built-in contacts that power the frog (no buying the 'snap relay' and adding it on). All other recent vintage Atlas turnouts have insulated frogs and there is no issue with applying power at the frog end - in fact I used terminal joiners (homemade ones, the Atlas ones are way too expensive) at EVERY joint on my layout which means I had feeders to both diverging legs of every turnout as well as the point end. The only place I had gaps was at the crossovers between the inner and outer loop and the reason for that was I was goign to make each loop a seperate power district.
With no new feeders connected there are pretty much only 2 ways to get a short. The simple one is maybe a pair of those unconnected feeders are touching one another. The other is if the extra track had resulted in a wye or reverse loop formation. If there is any way you can follow the rails and end up back on the same track but facing the opposite direction - you have a turning section of some sort. This will require additional gaps, but the nice thing about DCC is you can get devices that handle the polarity switch automatically, so all you'll have to worry about is running the train.
Thanks for the reply Randy. Nope, no reversing section as I purposely omitted any form of crossover between the mains even in the yard/staging area as the pike is not yet DCC. The remaining Atlas turnouts are new from the LHS (before I made the decision to buy all new Walthers DCC friendly and forgat about these 3 Atlas puppies) their regular $15 to $17 versions with the blackish-brown frog and guard rails.
The short evidences itself by just sitting a loco on the track and turning up the throttle. Slow movement regardless of throttle position. Never made it as far as going through the new turnouts.
So powering both ends of a turnout with insolated fog via home made joiner connectors is not a problem? I'll pull some of the feeders out that share a common hole through the roadbed to see if any had bare wires that could have touched.
Sounds like they are Custom-Line? Should not be a problem having feeders on any part, even the frog side. Might one to check to make sure they aren't defective and not insualting the frog and diverging rails properly - it's possible to get a dud. But assuming all is fine mechanically, the frog, while metal, is completely insulated from all rails. Power is continuous through the entire thing, no power routing is done. The right-hand approach rail should be tied to both right hand diverging rails, ditto the left rail. Assuming you are looking at the turnout with the points at the bottom, and you have white goign to the left rail, and red goign to the right rail, the feeders on the diverging tracks should go as follows (left to right): white, red, white, red
I use 2 holes for the feeders, I never put two in the same hole for the very reason of the possibility of a short. At least you knwo where to look, if you fixed the problem the previous time, and now it's back, it has to be in the section you wired since the last test.
Thanks Randy. It was a shared hole issue. I had stripped more insulation than I do when soldering to the rail ( vs under the joiner) as I find it easier to position, hide, yaday-yada. One of the little creeps had turned against me and was shorting on its hole-buddy.
All okay and I actual ran a 2 car inspection train behind PAs around the total railroad. Good grief, do I have a lot of track tweaking to do.