MRC 260, overload ? why ?


csxfan

Member
I just bought MRC 260 controler and connect it to my 60 feet layout and try to run first only one loco testing it. It runs a few inches and then it stops, the controler indicating the function OVERLOAD. I don´t understand, what´s wrong ? What does it mean, overload ? What´s the problem here ? How can I fix what ? Please help, thanks.
 
There could be 2 or 3 things wrong. If this is your 1st controller there's probably a short in the track wiring. maybe a wire crossed from one rail to the other. Another thing there might be a wire loose in the engine & it is touching the frame. Do you have any accessories hooked to the DC side of your transformer?
 
so it is a short, but where, perhaps in the feeder track I cannot see, no, the loco is fine, and there´s nothing hooked to the AC for accessories.
 
Are you using sectional or flex track? Are you running a Buss wire w/drops from ea. rail? Sometimes if one wheel on an engine is derailed it will cause a short. You could have a wire touching another wire someplace on the layout.
I'll keep coming up w/idea's when you answer the above.
 
Take the locomotive off the track, and open the throttle. If you still get an overload, look at the layout. If not, look at the locomotive.
 
no, I´m using bachmann e track, but to connect this controller I had to use a standard power terminal, disconnecting my DCC, of course.
b
 
As was posted, take the loco off the track and turn on the power, turning up the control knob slowly from 0-100. If the overload indication comes on, there is something wrong with the track circuit. If that happens, disconnect the 260 from the track. Turn it on and turn the knob up again. If no overload, then take a separate piece of track long enough to place the engine on, and turn up the power. (WATCH OUT THE ENGINE DOESN'T RUN OFF THE PIECE OF TRACK!) If you have another locomotive, try it on the track. If the engine runs okay, and there is no overload, you know for sure there is a short in your layout...somewhere. The trick is to run that down.

Next, re-examine your layout. Is there a hidden reverse loop somewhere? These can be tricky if the track layout is complicated enough. Check your control panel, if you have one, to be sure a wire didn't come loose somewhere, and is shorting against another wire or terminal post. (I just had a wire from a turnout switch machine break loose, so the turnout wouldn't throw one of the routes. Apparently worked loose when I opened the panel to install an auxilliary on/off switch for a traffic light!) Check your bus wires and feeders. If you have DCC, you may have inadvertantly connected a feeder wire to the wrong rail.
Best of luck!
 
thank you all guys, it´s gotta be a short somewhere, and yes the layout is very complicated, two levels with over 300 feet, with only one standard terminal track, or one DCC rerailer if I run DCC only, the problem is I don´t know much about electrical connections and polarity, my big amount of turnouts is a mess with many loops.
 
I am NOT any where near an expert on DCC. But if there is a short in DC, it may also show up with DCC. Although it would be a pain, here's what I would do: Disconnect all your leads at some convenient point so they can be easily reconnected (using suitcase connectors, etc. Reconnect one pair at a time until you get the indication of a short. Compare that to where the track shorting track section connects with the rest of the layout. Disconnect the bad leads, and start connecting other leads and see if you get a short on some other section. Compare that with your track plan and see if there is a related individual or set of turnouts. It may be something as simple as cutting gaps in some track.

You could also disconnect one pair of leads at a time and see if the short goes away. Also, try tracing ONE rail around your layout and see if it winds up connected to the other rail somewhere. (I term the rail closest to me in front of the control panel as the South rail, and the other one the North rail. The terms are arbitrary, but you need some reference point.) For example, if your layout forms a "folded dogbone", and you have a crossover between the "double main line" (which it isn't), you have created a pair of reversing loops. You therefore need both rails between the turnouts insulated from each other, plus a DPDT switch for one or the other, or one of those DCC auto-reversing gizmos or somesuch. (I'll leave that to the DCC experts. I run DCC, but my layout is set up primarily for DC, so I have individual blocks, and DPDT toggles where I have polarity conflicts/reversing loops. I use a MRC Tech6 6.0, which can be set for DCC or DC locos.)
 
thank you all guys, it´s gotta be a short somewhere, and yes the layout is very complicated, two levels with over 300 feet, with only one standard terminal track, or one DCC rerailer if I run DCC only, the problem is I don´t know much about electrical connections and polarity, my big amount of turnouts is a mess with many loops.

If I read and understood you correctly I think I have this correct.

One, you need more than one feeder attached to the layout. One power feeder will not work. Feel the wires going to that one feeder track, are they getting warm? It could be that the resistance of the track alone over that distance is causing the overload, the power pack just can't push enough power through that one connection for the whole layout and this will show as an overload. One wiring "rule" is, (esp with DCC), never rely on one feeder to power the entire layout, unless it is a very small one.

Two, have you placed insulated gaps anywhere in the layout? In case you have some reversing loops that you haven't seen or don't know about, a direct short will show here without any gaps.

Three, can you post a copy of the plan you followed? It makes it a lot easier to diagnose a problem if we can see the plan for ourselves. The plan should show where the feeder(s) are located.

Four, If you have a hobby shop in the area, check and see if they have any books on wiring a layout. Kalmbach Publishing, (your friendly MR publishers), have several, as does Cartsens, (the RMC publishers). If no hobby shop, these can be found online.

While wiring a layout correctly is a lot of work, its not that hard.:)
 
Yes, I have only one feeder, one Bachmann es track rerailer. How and where can I place another one, should I use those from Atlas, how and where should I connect them ? How can I connect other feeders to Bachmann DCC and MRC 260 ?
 
You don't need any of the so-called Terminal tracks. I would solder the feeders to the rails where ever they are needed. This can be done to any of the rail material on the market, including the E-Z track that bis steel.

If you don't know how to solder, its very easy to learn. I would start with some scrap wire and a scrap piece of track. Radio Shack, any electronic store, and even walmart, k-mart, lowes and the hodo has soldering irons & solder. If there is an LHS in the area, I bet they have one. Just make sure that you get electronic solder, and not acid core. Acid core is used in plumbing and the solder joints have a practice of deteriorating when electricity is passed thru it.

While at the LHS, pick up a book on wiring a layout. Kalmbach, (MR), and Cartsens, (RMC) have several that will teach you how to wire the layout as it needs to be done. As I said earlier.

But it would be nice to see a plan. That way we could assist you in finding problems in the plan, any hidden reverse loops, esp any place that a gap needs to be put to prevent shorts.
 
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aha, let´s say I will manage to solder, but how do I wire those feeders to my MRC 260 2 DC screws and my Bachmann Dynamis ? no, there is no LHS around here, I´m down here in Nicaragua, Central America. I don´t know what to get, like some connector bus or something, tell me, show me, please, what do I need ? I hope I get it on ebay.
 
I would suggest you go to the RailroadBookstore.com at the top of the page. Look for books on wiring your model railroad for DC (since you are using the MRC 260). As far as hardware is concerned, you need wire, terminal blocks (these are strips with a double row of screwposts to which wires can be connected), and if you are breaking your layout into electrical blocks, some Single-Pole, Single-Throw (SPST...ON/OFF) electrical switches...the minature ones will do, and probably at least two or three Double-Pole, Double Throw (DPDT) switches for wiring your reversing loops (one to a reverse section). Order the books first. Then look at your layout before ordering equipment.
 
... and if you are breaking your layout into electrical blocks, some Single-Pole, Single-Throw (SPST...ON/OFF) electrical switches...the minature ones will do, and probably at least two or three Double-Pole, Double Throw (DPDT) switches for wiring your reversing loops (one to a reverse section). Order the books first. Then look at your layout before ordering equipment.

Instead of SPST, I would use all DPDT switches, with center off. This would allow you to be able to not only turn a block off, but would allow you to add either a second DC throttle, or be able to go from a DC system to a DCC system with the flip of a switch.
 
Instead of SPST, I would use all DPDT switches, with center off. This would allow you to be able to not only turn a block off, but would allow you to add either a second DC throttle, or be able to go from a DC system to a DCC system with the flip of a switch.

That is actually the way I do it, but I didn't want to add complexity to the suggestion until csxfan is able to get ahold of some books on wiring. In point of fact, I actually don't use the "other" side of the individual blocks' DPDT. I set it up so I could wire up for individual control for each block. However, I also have a single, larger DPDT on my control panel that allows me to connect my MRC Tech6 6.0 to the entire layout, or to switch to a 260 for my DC locos. That way, I can be sure I don't connect DCC to my DC-only locos (although it can still happen if I'm not careful where I park them. Since I am a one-man operation, I'm not too worried about what another operator is doing elsewhere on the layout.
 
For a one man operation, it may be better. And the one DPDT acting as the switch between the systems is a good idea. But in my mind you loose the flexibility afforded by the DPDT's. It sounds like with your system, its either DC/or DCC, whereas with the DPDT's it can be DC and DCC. He can run both types, DC & DCC, at the same time, keeping each type of control separated by the train's routes.

Plus you have to consider his location in Central America. He can't go around the corner to get the supplies, so the best for him would seem to me would be to get the supplies at one time that offers the greatest flexibility from the start.

But that will be his decision, and not ours. Until he gets the wiring books, I think we shouldn't start a discussion along those lines.

Csxfan, if you want to get a jump on learning wiring while you wait on those books, go to
http://www.wiringfordcc.com/ and for some basic DC wiring, go to here;

http://modelrailwaynews.com/model-railroad-wiring-basics-for-dc-control-wiring/

The second one also have links to other sites for basic DC wiring.
I hope that these sites get you started correctly. But still get the books! They will give you more detailed explanations and have more examples that will help your understanding of wiring a model railroad.
 
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"For a one man operation, it may be better. And the one DPDT acting as the switch between the systems is a good idea. But in my mind you loose the flexibility afforded by the DPDT's. It sounds like with your system, its either DC/or DCC, whereas with the DPDT's it can be DC and DCC. He can run both types, DC & DCC, at the same time, keeping each type of control separated by the train's routes." (snip) - Cjcrescent

That's true. And someday, I may add wiring to the other side of each switch's DPDT Ctr OFF toggle. But since I have difficulty walking and chewing gum at the same time, my system HELPS (not absolute...I can throw the main toggle the wrong way with a DC loco "in harm's way") keeping from frying a now-discontinued Canon coreless motor! ;)
 



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