Just getting some track and joiners out of storage that have been boxed up for 15 years or so. Put a layout together - less then 50 feet of track. Using a new power pack and am getting the overload light bright red.
Would this be because there is too much track or because of dirt and corrosion build up on the joiners and rails.
If it is the latter, do you know of any good way to clean a lot of track and joiners without scrapping and scrubbing each one individually?
Dirt wouldn’t cause this unless it had a layer of corrosion clear across the ties. Dirty rails and joints cause dead spots, not shorts. You didn’t mention if it is shorted on empty track or only with cars/locos on it. Then start taking it apart piece at a time till light goes out.
Possibly you have installed a reversing track without insulating rail joiners, or have more than one pair of electrical feeders with wires going to opposite rails. Or wire connections at the power pack terminals are touching each other. Any one of these will cause a short circuit which will indicate on the power pack by activating it’s current limiting safety device.
I reduced my layout to a simle oval with no reversing track and with only one set of turnouts to add a parallel bypass around one of the ends. Nothing fancier than that. Only one set of feeders and triple checked and rewired my feeder connections from the power pack. Removed my older turnouts. Still getting the problem, even without a load on the track.
I’m wondering how much affect old parts mixed with new parts has. Also, I know a lot of my old joiners are bent, some too loose, some too tight. Some track is nickle and some is standard (steel? copper?). I can’t see how this would cause an overload. I’d think it would just cause poor contact and power flow through affected areas.
Yoy might try disconnecting the power pack from the layout and wires and see if you have the problem. Then add the wires and turn on the power pack. Then connect it to one piece of track and check for the problem and keep going one piece at a time until you do (tedious I know). The last thing is the problem. Old or new might have the problem - the one because of age and the other because of manufacturing failure. My current layout has items ten years old (plus who knows how long on the dealer’s shelf) and stuff made this year and it all works together fine.
Enjoy
Paul
BY “connecting to one piece of track”, do you mean wire from power pack directly to each piece as those pieces make up the entire layout? Or pull each piece from the layout?
If it is the former, wouldn’t the rail joiners come into play and transfer the trouble from whereever it is to this one piece you are testing? Would it be OK to use alligator clips?
I would start with 1 piece of track and verify it’s good. Add pieces till problem appears. Or use alligator clips and chk 1 at a time. I would start with turnouts. They may have a frog switch that is stuck. Then chk power tracks next if you use them. Also turntable can cause this if not installed correctly or route switch stuck. Good luck.
If the turnouts are the all metal, non-insulating frog type this could be it. When placing these type of turnouts frog to frog you need to place electrical gaps in the rails between the frogs. Test by placing the points in the center position, wedge a small piece of wood or cardboard in to hold them there so the points do not contact either of the stock rails; then see if the short has gone away. Also the feeders must be connected to the point end of the turnouts, not the frog end.
Here’s a short locating tip if you have or can purchase a digital voltmeter, and above is not the problem. Using the ohms function of the meter will prove you have a short, which you know already, don;t measure ohms with power applied to the rails or you can damage the meter. The ohms function cannot resolve low enough resistances to find the short. But by using the lowest voltage range possible (millivolts, or thousandths of a volt) yiu can measure the voltage drop along the rails when applying brief periods of power from the power pack, ie set up the meter with alligator clips to the rails, turn on the power pack, quickly note the meter reading, then turn power off again before the powerpack overload detector triggers and shuts off the power (you need to have current flowing through the short to measure the voltage drop produced). Then move the alligator clip leads and try again.
The farther the clip leads from the physical location of the short, the more voltage drop produced by the current flowing through the resistance of the rails. Move the clip leads in the direction that results in a lower
What I had in mind was building the layout one piece at a time testing after each piece is added. The idea is to work incrementally from not having the problem to having the problem. Then test by itself, the last thing added since it may be a combination causing the problem. Alligator clips are okay, but do test the wires you are using, particularly if they are a ribbon set where the wires are attached to each other except at the ends (insulation could be gone between them). Since you’re looking for a short, I don’t see the rail joiners being the culprit.
Good luck
Paul
What if the transformer is the problem? Maybe there’s something stuck inside it, or a internal fuse shorted out. Try out another transformer on the track, and tell me if that helps any.
Good luck [:)]
I made a simple 12 piece circle and powered it with the power pack I was having trouble with on the larger layout. It worked fine on my circle, so I made the assumption that I do not have a problem with the power pack. Is that a valid conclusion? Or could the power pack be the problem given a new set of circumstances on a more elaborate layout?
gchenier: Thanks for the advice, I’ll try it tonight, but a lot of your terms are new to me. Sorry for being a ‘dummy’, I’m kind of new to this model railroad world, but could you define some of your turnout terms: frog, center position, stock rails, feeders, point end.
Feeders are the pair of wires that bring power to the track.
The frog is the V shaped section of the turnout where the two inside rails of the diverging tracks meet. The frog end of the turnout is the end that branches into the diverging tracks.
The points are the flattened ends of the moving rails, they press (one at a time) against the inside surfaces of the stock rails to guide the wheel flanges into the selected route. When the point touches the stock rail it makes electrical contact to the stock rail. The point end of the turnout is the single track closest to the points.
Some turnouts are made with the points each permanently electrically connected to their respective stock rail by another path within the turnout construction. These types will have an insulated frog, one with some of its pieces made of plastic so that the inner rails of the two diverging tracks never make electrical contact to each other. Where the frog actually tapers down to a sharp point (not the same piece as the moving points, terminology allows only one word for different parts), this area is also plastic. With this type of turnout there is no need for rail gaps at the tracks leaving the frogs, but their drawback is a locomotive power pickup wheel momentarily loses electrical contact as it passes oder the frog. This can lead to stalling.
Other types of turnouts are made with the frog all metal to avoid the stalling problem. Since the two inner rails of the diverging tracks thus come together at the frog and make electrical contact, they effectively have shorted the rails together, this must be overcome by placing electrical gaps
Just getting some track and joiners out of storage that have been boxed up for 15 years or so. Put a layout together - less then 50 feet of track. Using a new power pack and am getting the overload light bright red.
Would this be because there is too much track or because of dirt and corrosion build up on the joiners and rails.
If it is the latter, do you know of any good way to clean a lot of track and joiners without scrapping and scrubbing each one individually?
Dirt wouldn’t cause this unless it had a layer of corrosion clear across the ties. Dirty rails and joints cause dead spots, not shorts. You didn’t mention if it is shorted on empty track or only with cars/locos on it. Then start taking it apart piece at a time till light goes out.
Possibly you have installed a reversing track without insulating rail joiners, or have more than one pair of electrical feeders with wires going to opposite rails. Or wire connections at the power pack terminals are touching each other. Any one of these will cause a short circuit which will indicate on the power pack by activating it’s current limiting safety device.
I reduced my layout to a simle oval with no reversing track and with only one set of turnouts to add a parallel bypass around one of the ends. Nothing fancier than that. Only one set of feeders and triple checked and rewired my feeder connections from the power pack. Removed my older turnouts. Still getting the problem, even without a load on the track.
I’m wondering how much affect old parts mixed with new parts has. Also, I know a lot of my old joiners are bent, some too loose, some too tight. Some track is nickle and some is standard (steel? copper?). I can’t see how this would cause an overload. I’d think it would just cause poor contact and power flow through affected areas.
Yoy might try disconnecting the power pack from the layout and wires and see if you have the problem. Then add the wires and turn on the power pack. Then connect it to one piece of track and check for the problem and keep going one piece at a time until you do (tedious I know). The last thing is the problem. Old or new might have the problem - the one because of age and the other because of manufacturing failure. My current layout has items ten years old (plus who knows how long on the dealer’s shelf) and stuff made this year and it all works together fine.
Enjoy
Paul
BY “connecting to one piece of track”, do you mean wire from power pack directly to each piece as those pieces make up the entire layout? Or pull each piece from the layout?
If it is the former, wouldn’t the rail joiners come into play and transfer the trouble from whereever it is to this one piece you are testing? Would it be OK to use alligator clips?
I would start with 1 piece of track and verify it’s good. Add pieces till problem appears. Or use alligator clips and chk 1 at a time. I would start with turnouts. They may have a frog switch that is stuck. Then chk power tracks next if you use them. Also turntable can cause this if not installed correctly or route switch stuck. Good luck.