Still, I continue to wonder.
Rich
That was only the OP’s second post, so it will be a while. But there is deffinately something going on, I really believe it is not because a lack of feeder’s, but That’s My Opinion. What I am having a hard time with though, is why, no breakers, or fuses, blowing? Something is drawing a lot of current, to be heating the rail’s.
Cheers, [D]
Frank
Can’t be drawing THAT much current. Or the breaker WOULD trip, or there would be walking O’s on the display for overload.
But it doesn;t take that much. 2 amps at 12 volts is 24 watts, that’s definitely warm enough to feel hot - those little night light bulbs are like 7 watts and are plenty hot. Yet 2 amps is below the limot of the original Zephyr as well as the Xtra, so the breaker would never trip.
This is why the quarter test is SO important. The quarter test is SETTING the quarter on the rails, not pressing down to get extra good contact. If the breaker doesn;t trip, then a loco could derail and short the track in a way so as not tro trip the breaker. With a typical 5 amp system at the usual 15 volts, you cna get over 70 watts flowing through a ‘short’ and not trip the breaker - and a 70 watt light bulb will DEFINITELY melt plastic things. The problem is too small a bus or not enough feeders, resulting in enough resistence in the circuit that the current is limited to something less than the booster’s trip value. Avoid this at all costs - use the quarter test to make sure things shut down when shorted.
In the OP’s case, it could be one crossed feeder somewhere - if the feeder is small enough, it will draw power but not enough to actually trip the breaker. That would be true if the rail joints heated up even with no locos or rolling stock on the track. But if the joints ONLY heat up when trains are running, then it’s not enough feeders coupled with joiners that aren’t very tight.
–Randy
Thanks for all of the feedback. At the time of my initial post I did not have any feeders attached – I had just laid the track and was testing the plan with a single engine powering the rails with my Zephyr xtra via alligator clips. Since then, I’ve attached about half a dozen feeders (my bus is 14 AWG and my feeders are 22 AWG). I haven’t had any overheating problems since then. It appears the major problem was a lack of feeders and rail that was too loosely connected. Since I didn’t have any feeders attached yet, crossed feeders aren’t the problem, but I do have a couple reversing loops that need to be gapped and conected to an auto reverser.
My current plan is to attach additional feeders as I glue down the track, and I’ll definitely use the quarter test as I go. I have planned all along to run feeders every 3 feet or so – as many of you have noted too many feeders won’t cause a problem, but too few may. Since my initial post, I’ve also stopped powering the track via alligator clips, and instead have started powering the track via my power bus. Incidentally, my layout is currently broken up into 3 major power blocks – 1) the industrial/switching/intermodal yard, 2) mainline, and 3) tortoise switch machines (planning on 25-30 switches). I’m also planning a short branchline which I plan to power through the mainline block.
As for my Zephyr, I’ve been planning to upgrade my command station to the Super Chief 5 amp set to provide more power for the yard and engines. Once I confirm the Zephyr is functioning properly I plan to use it on the programming/test track on my work bench.
This seems to make sense to me, but I defintely welcome any additional feedback you folks could offer me at this early stage.
That is correct, if the rails are getting hot with no locos, he has a crossed feeder. If they are getting hot from using a loco then he has a resistance concern. Could be either the feeders or joiners. Enough feeders will over come bad joiners and conversly tight joiners will eliminate the need for many feeders, at least for a while.
Pretty simple to diagnose, disconnect the pack, remove all rollling stock and check for continuity across the rails. If continuity is present, he has crossed feeders. If not, check the resistance of each rail from end to end. If resistance is high he has loose joiners, if rail resistance is low, add feeders.
I suspect he is trouble shooting his layout or he is a lone wolf and does not show up much. Only 2 post.
Rich
Martin is right. A bad connection will get hot. If the rails are getting hot, they could be conducting the heat away from the trouble spot(s). Also do the quarter test to make sure your circuit protection is working, you might have a short that isn’t detected by the booster. With light gauge wiring it might be fooled and doesn’t respond to a large current draw that is flowing.
First of all, thanks for all of the advice! I’ve followed various discussions for over a year, but this was my first posting, and I wasn’t sure if I was going to get much if any feedback. So thanks!
At the time of my initial posting I hadn’t attached any feeders to the bus yet, and so I knew it couldn"t have been a crossed line. I had just finished laying the track and wanted to test an engine on it – that’s where the alligator clips came into play. I also haven’t installed any switch machines yet, but that’s coming soon… I hope.
Since then I’ve attached feeders to those sections of track that I have already glued down (14 AWG bus and 22 AWG feeders), and I haven"t experienced any issues with heated rails. My plan all along has been to attach feeders every 3’ or so to ensure power throughout the layout. I have also stopped using the alligator clips to power the rails, since the bus is not connected. Incidentally, I have already broken the layout into 3 major power blocks: 1) mainline, 2) yard, and 3) tortoise switch engines (I’m planning on about 25-30). Each power district is routed through its own circuit breaker. I will have a short branchline come in at some point, but I was planning on adding that to the mainline bus. As for the Zephyr, I’m planning to shelve it temporarily – I’ve planning to upgrade to the Superchief 5amp system for some time, and now seems a good time. Once I verify its functioning properly I’ll move it to my programming/test track.
So it sounds like my next course of action should be to attach feeders as I glue each new section of track in place, and I will definitely run the quarter test as I go.
LION does not have DCC. LION does have Analog Automation (of his own design) which places 15 amps (at 10 volts) on the tracks at all times. It has NEVER heated up. Amps on the tracks are not going to heat things up, DRAWING those amps will, but plenty of feeders take care of that just fine.
LION has gotten some shorts, but sometimes did not draw enough amps to trip the breaker. Meter showed only about 3 amps (dead short through a resistor) which will not impress a 15 amp power supply, so the resistor burned up.
In other words you could have a dead short that is not quite dead. (as if it had a resistor in the circuit) [Your LOCOMOTIVE IS A RESISTOR], and so it does not trip.
Get an automotive tail lamp, put it in series with your layout, and during normal operations it will remain dark, as there is not enough apmerage passing throught the filiment to light it. But if there is a dead short, all of the amperage will pas through the light and it will light up, telling you of the problem, and by the way, eating the energy so that things to not heat up or start tires.
LION will guess that you have a reversing loop, but because it is gapped there is no short, but when the locomotive crosses it, it bridges the gap, causing a short that because of the resistance of the motor does not blow the breakers, but does heat up the environment.
INSPECT YOUR WIRING.
ROAR
If you don;t plan to run more than 22 locos at a time, don;t buy a Super Chief, get a Super Empire Builder, DB150 and DT402 throttle, and keep the Zephyr Xtra as the command station. You’ll get the 5 amp track power (plus can use the Zephyr Xtra 3 amps for another power district) and still have the dedicated program track and the other features of the Zephyr, for less cost.
That’s exactly what I did, my layout it currently too small for the 12 loco capacity of my original Zephyr, let alone more than that, so I picked up a SEB set to get the DB150 plus a DT402 throttle. My Zephyr is under the layout, I haven’t used the console on it since I bought a DT400 way back when, the DB150 powers the track, and the Zephyr runs to all my stationary decoders.
–Randy
I am still trying to come to grips with the notion of heated rails on a DCC layout.
So, what we are saying is that too few feeders can result in heated rails without tripping the booster?
Can this only happen with shorts or also on a wiring with correct polarities?
What effect does this have on parked locos on those heated rails?
Rich
It requires a combination of too few feeders and loose rail joiners. I’ve never noticed this over two layouts now even though both were initially tested before connecting all of my feeders, and no, I don;t solder my rail joints, just on curves. I Do use NEW joiners when I lay each section of track - I have some that have been connected and disconnected many times and they slide on with almost no resistence. I use those when trial fitting things and cutting flex to length. But when I go to put the next piece of track in place for good, I grab a fresh pair of joiners from the package. - the kind you can barely get on because they are so tight.
The loose fitting joiners form a poor connection that puts some resistence in the line, and if power is drawn from a point past this, the current flowing through this resistence will generate heat.
Have you ever had an outlet in your house where the contacts were worn and plugs fit in loosely? The plug on the appliance you have plugged in there gets warm or hot. Or a light switch that’s failing, sometimes they make a siggling sound - and get hot. Same principle. In my previous house, I had to replace nearly every receptacle in the place, they all had at least one of the two outlets so loose that plugs would just fall out. Cheap shoddy work. It’s where I learned to hate solid wire, pulling the old outlet out of the box, and then trying to push the replacement back in. Especially on middle of the circuit outlets where there were a total of 4 wires.
–Randy
You will hate it even more if you use stranded wire and a single strand reaches out to touch another, or the metal box. They WANT to do that, you know.
Yes stranded is more flexible, but if the wire is not normally subject to stress, solid is far better.
ROAR
Posted by richhotrain on Thursday, November 28, 2013 5:36 AM
I am still trying to come to grips with the notion of heated rails on a DCC layout.
Electrical concerns are the #1 request for help I see, and many are by very experienced technicians. Lots of people have a hard time with it.
So, what we are saying is that too few feeders can result in heated rails without tripping the booster?
Yes, as long as current is less than the breaker or fuse, it will not trip. And current is dependant on load, which is the locomotive (s).
Can this only happen with shorts or also on a wiring with correct polarities?
A true short will open the breaker, so if the breaker is open, no current can flow. No current flow = no heat. Incorrect polarity will open the breaker, unless a feeder is so small as to act like a resistor. And if thats the case, you really do not have a short.
What effect does this have on parked locos on those heated rails?
None
Rich
Maybe for house wiring, but I will never use solid for my main power bus. Feeders - yes, but thin solid wire is easy to form and easier to solder to the rail than stranded wire.
–Randy
Thanks, Jim.
I asked that last question about parked locos because all of my track is powered at all times as long as my DCC booster is powered up. I know that some people cut off power to loco storage tracks, so I just wondered about the effect of heated rails on dormant locos.
Rich
My guess would be if the rail isn’t so hot it’s melting ties, then the trains are OK sitting on it. Of course if it’s melting ties and the breaker hasn’t tripped, there is a serious problem.
This has been a very interesting topic. Reading through the posts we can see that the OP had a temporary wiring arrangement. Now he has powered the buss and using feeders his problem is being solved.
To expand on this example:
We all have opinions on how layouts should be wired, how many feeders, and whether or no to solder joints etc etc and we all have different experiences and results. The title of this thread shows what can happen when the “conductors” are inadequate.
I am no electrical wizard at all, but I get the basics. A short circuit only shows as a short if the wiring is adequate, if wiring is inadequate (too small, too long, poor conductor, etc) then that same short shows as resistance (load) which results in heat.
I hope this thread is helpful to any DCC newcomers. Lets not have another debate on stranded or solid wires, please.
Let me second this thought to emphasize the point. Some will use the same rail joiners over and over again. I put a rail joiner on and connect the track. If I have to take it apart for some reason it gets a new joiner. The problems a used, loose, sloppy joiner will cause is not worth taking the chance on saving a few cents by re-using them. One and done.
Soldering a loose and sloppy joiner just fills the gaps between the rail and joiner with lead and tin. Lead and tin are not good conductors of electricity. If you are going to solder, make certian there is a good electrical contact with a tight joiner to begin with, then the solder’s function is to hold that good connection in place not be the connection.
That is one of the best explainatioons regarding soldering. Thanks Texas Zepher.