NCE telling me there is a short.

[PrairieKnight]

So I finally got all the Atlas feeder rail joiners connected to the 14ga bus with "suit case" connectors. I plugged in the NCE power cab controller...and...nothing...but a blinking red light on the control panel where the "phone jack" type plug connects. The NCE manual states that when the red light is flashing or not lit at all...try this... unplug the bus wires from the back of the control panel...I did that... if the red light is solid with the bus unplugged...there is a short in your wiring. Low and behold.. the red light is nice and bright when the bus is not plugged in to the control panel. So...I welcome any suggestions on next steps to find the problem.

This is my first layout. It is a 4 X 8 double oval with two yard areas based loosely on the Virginian Railroad from Model Railroader. I am thinking that my options are:

1. Use a multi-meter to measure the voltage where the bus wires are connected to the back of the NCE control panel. NCE states this should be about 13.8. Then go to each set of feeder rail joiners.. starting with the ones on the bus closest to the control panel...and measure each with the multi-meter. I am thinking that when I find where there is no voltage to the track feeder wired connectors... there is my short in the bus/feeder connection. A possible fix when I find the problem would be to cut and splice the feeder to the bus with wire nuts..or possibly try to put in a new suit case connector in the exact same spot where the old one was attached to the bus. There is probably a better fix then the two I just mentioned...but I dunno.

or..

2. For go the above and cut out and remove the bus from the feeder wires. Start over with a new bus..maybe use 16ga this time.. and wire in the feeders. I am thinking this would be done one set of feeders at a time. After wiring each set of feeders to the bus (considering wire nuts as opposed to the suit case connectors this time. I am not good at soldering) I would then plug the bus into the NCE control panel and make sure that I still have the little red light as I work my way around to each of the feeder wires.


Any suggestions and advice on my next steps in finding and fixing this are greatly appreciated.

 

[santafewillie]

Good Morning PrairieKnight
Let me first start by saying that I do not do DCC, but I do know something about electricity.
1. The gauge of your bus wires is irrelevant to shorting. 14ga is better for a bus than 16ga.
2. The connections to the bus, whether soldered, wire nuts or suitcase connectors are also irrelevant to shorting unless you have one incorrectly attached to the wrong leg of the bus. This is where you should look first. Make sure that all of your feeders are connected to the correct leg of the bus. This is most likely the cause unless...
3. Do you have an uninsulated reverse loop? If so, it needs to be isolated from the rest of the track/bus and be wired accordingly.
Good luck.

Willie

 

[Greg@mnrr]

Is there anything laying across the tracks or turnouts? I once had a piece of .032 solder laying between the rails and shorting out my DCC. It took almost two days to find it.

Or, is there a loco derailed and shorting out the system?

Thanks.

Greg

 

[Red Oak & Western]

First, what Willie said. Great advise.

Second, what Greg said. Make sure all your rolling stock is off the layout, then "walk the rails" looking for any foreign objects.

If not a reverse loop problem (I'm only vaguely familiar with MR's Virginian layout plan), did you use "DCC friendly" turnouts? I'd set all the turnouts to the through position, then re-check. If you have a VOM (multimeter), clip the test leads to the rails. The reading should be really high or --- or blinking, depending on how your meter displays an "open" circuit. If it shows a low value, you still have a short somewhere; recheck per Willie's suggestion #2.

 

[Iron Horseman]

It is a 4 X 8 double oval with two yard areas based loosely on the Virginian Railroad from Model Railroader.

How loosely? As presented by MR there are no reversing loops, but I can easily see how one could be introduced.

So I finally got all the Atlas feeder rail joiners connected to the 14ga bus with "suit case" connectors.

I agree with Red Oak and santafewillie. My guess is hot frog turnouts or one of these connections is backwards. I would start with the turnouts (what brand/type are they) if all insulated frog type, I would move to examining each feeder one by one. Trace the wire from track to bus and make certain they are all aligned properly.

2. For go the above and cut out and remove the bus from the feeder wires. Start over with a new bus..maybe use 16ga this time.. and wire in the feeders. I am thinking this would be done one set of feeders at a time. After wiring each set of feeders to the bus (considering wire nuts as opposed to the suit case connectors this time. I am not good at soldering) I would then plug the bus into the NCE control panel and make sure that I still have the little red light as I work my way around to each of the feeder wires.

Yes (not about the gauge of the wire or connection type), but as a general rule always do one electrical connection at a time. Testing each one. That way when suddenly there is a short, one knows it is caused last connection done.

 

[PrairieKnight]

Gentlemen..you guys are the best.

I started with Willie's reply and read through them all. I found two problems. One of the feeder pairs was crossed, fixed that. I then found that one of the feeder wires was not secure in the suitcase connector. Replaced that with wire nut. I followed the quick start steps in the NCE manual... And wow.... It works. I appreciate the replies. Thank good ness I found and fixed the problems before I had to go through all of the advice. I was getting nervous reading about the frogs and the reverse loop.

I am using Atlas remote snap switches on the layout. I have not wired them in yet.. But the Walthers locomotive went through them just fine.

Thanks again

 

[santafewillie]

Atlas remote switches are DCC friendly, you shouldn't need any additional or special wiring. Powering the frogs is optional but not always necessary unless you have some finicky locomotives. If everything you have runs through with no trouble, then just leave them alone.
Willie