I'm a self-taught novice model rr'er (3 years off and on, more off than on, but now a medical condition is giving me a lot of free time in need of filling, so...). My question is so simple, I'm almost embarrassed to ask, but I have no choice.
I'm building a simple HO DC layout with a double loop, a siding and a spur, with six remotely controlled (I hope) turnouts. The track is all laid and tacked down, and wired for track power (switches aren't wired yet).
My question? Why will my brand new locos run in only one direction, right to left?
I knew the electronics would be my downfall. I can't solder for beans, so I don't do anything requiring it. I'm using a standard Atlas power pack as primary, and an Athearn as back-up -- the problem happens with both. I have both a terminal joiner for power (didn't work very well), and terminal track. I'd like to post pictures of how it's wired, but doing so here is a challenge to say the least. I have 20 gauge red wire from the common rail, or in the case of the terminal joiner, the common-rail wire, to the red attachment of the power pack. It's a bit dicier with the Athearn since the polarity at the screws is not labeled. The locos, both of which are Walther's HO models, both "DCC compatible." (again, no interest in DCC at this time).
I have checked the track a dozen times to make sure everything is properly connected and cleaned, and there are no short circuits. I'm using the Atlas wiring book as my guide.
Bottom line: My brand new locos will run only one direction on my HO DC layout. The problem is almost certainly in the wiring. Any ideas?
Mel is correct. To me it sounds like the reversing switch in your power pack is faulty. That is rare, fortunately.
Try reversing the wires that come out of the pack to the track (reverse them anywhere - at the pack or at the track). The engines should now go in the "other forward."
If the reversing switch is faulty (and assuming we are not talking a brand new DC power pack that can be returned) it is possible to save the pack and use an Atlas reversing switch; somewhat more cumbersome but frugal. I think the Atlas 220 controller would work, although it is intended for a reversing loop situation.
There may be cheaper reversing switches out there - any double pole/double throw toggle switch would work - but they may call for going to other than a hobby shop.
Dave Nelson
dknelsonMel is correct. To me it sounds like the reversing switch in your power pack is faulty. That is rare, fortunately.
With both power packs? Yes, more than extremely rare.
The DC motors turn one direction only...at a time. In the same length of powered track, both locomotives will move one way...only....including only one direction around a loop. If you take one locomotive and turn it around, they'll do the same thing...both moving the same direction around the loop. This is because, while you have reversed the direction one of them faces, you have also reversed the power orientation below the engine...you have reversed the polarity of the rails. When you reversed the power below the locomotive whose motor now has been rotated 180 degrees, you make that motor spin the other way. Logically, it still moves the same way as the other locomotive.
Is this what you mean?
OK, just to clarify, you don't mention the black wire. Do you have two wires from the power pack, one to each track?
AND, once again, just to clarify, do you have both power packs connected to the track ? Or do you try just one power pack at a time?
AND, are you running both locos? together, or trying each one seperately?
Mike.
My You Tube
Let me try to clarify and give a little more detail. I only had time to try one thing, and gather some details. For clarity's sake, let me start with my terminology definitions.
"Forward" and "Reverse" are vague, relative terms. "Forward" to me means the front of the train moving clockwise (to the left), "Reverse" when it's moving counter-clockwise (to the right) .
I am only referencing one power pack, a Railpower 1370 which I know works fine.
I'm also only talking about a terminal rail -- I didn't have time to test the terminal joiners as a power access point. To me, when looking down at the power pack the "fwd/rev" switch is: left = fwd, right = rev.
The loco I used (and for continuity's sake the one I will continue to use to carry out any other tests) is a Bachmann #62812 GP9 DIESEL (DCC EQUIPPED) - Bangor & Aroostock #80. I did not bother using the other -- I won't be running it, it's just a hair too long for my layout -- so I wouldn't muddy up the waters any further.
Power is supplied through a terminal track connection, #20 Red to the common rail screw, thence to the left DC screw on the pack; #20 Black from the negative (non-common) screw on the track to the right connecting screw on the pack.
I hope I make sense.
Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise).
I hope the above helps, and doesn't make thing murkier.
Ajhall Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise). I hope the above helps, and doesn't make thing murkier.
dknelsonSo if the "front" of a locomotive goes right, and you pick up the locomotive and turn it around and put it back on the track without touching the reversing switch on the power pack, it should still go right.
The OP is saying when he turns the loco 180 degrees it doesn't go at all. The forward and reverse switch on the power pack does nothing. With his loco at the 6 o'clock position on a roundish layout, the nose facing 5 and the tail facing 7, the loco moves in the direction the tail is pointed.
I don't have a clue how that can be.
Henry
COB Potomac & Northern
Shenandoah Valley
OK, so I looked up your loco,
http://shop.bachmanntrains.com/index.php?main_page=product_info&cPath=258_288_290&products_id
It is DCC equiped, with a dual mode decoder. If you bought this from a dealer, out of the box, it should be set for DC.
If you bought this from a previous owner, like from Ebay, it may have been switched over to DCC. Not that this might have anything to do with the loco running in one direction only. Just thinking this through outloud.
What do the lights do? With the directional switch on the power pack, does the light on the loco change? from the front to the back?
EDIT: OK, the link doesn't work. When you go to Bachmann's site, and look at HO scale diesel locomotives, scroll down, click on GP9's, you'll see what I'm seeing. For whatever reason, it doesn't link.
http://shop.bachmanntrains.com/index.php?main_page=index&cPath=258_288
A second try.
AJ -
If I am understanding your post correctly, your loco only runs one direction, and only when facing that direction?
As in it only will run by the power pack when facin left, moving right to left?
And when you flip the switch to reverse, to run left to right, it doesnt run at all?
If the loco faces right, it won't move at all either direction?
Curious, if this is correct, what is your second loco? Is it also DCC Equiped?
And, my silly question time, when you are placing the loco on the track facing right, it's on the rails fully, and the power is turned back on, right? (Sometimes the silly reason is it, but something tells me it is not this...)
Ricky W.
HO scale Proto-freelancer.
My Railroad rules:
1: It's my railroad, my rules.
2: It's for having fun and enjoyment.
3: Any objections, consult above rules.
Dave -- I just want you to know there is nothing about your post I find remotely insulting or offensive.
dknelsonThe electrons don't know where the cab or front of the locomotive is and don't care. That's the kind of metaphor my brain likes. Ajhall Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise). I hope the above helps, and doesn't make thing murkier. Ah I think I see, although your description is a bit murky to me. In DC forward and reverse are not related to the locomotive's front and rear, but to any thing on the track. Instead of thinking forward and reverse think of "this way" versus "that way." So if the "front" of a locomotive goes right, and you pick up the locomotive and turn it around and put it back on the track without touching the reversing switch on the power pack, it should still go right. And vice versa The electrons don't know where the cab or front of the locomotive is and don't care. DCC is different but not relevant to this discussion. This is why you can have, say, F units back to back and they'll run in the same direction (assuming they are wired to NMRA standards) and not pull or push against each other. I do not mean to be insulting and please do not take offense. You would benefit from a good book on DC wiring. Linn Westcott wrote one for Kalmbach as did Andy Sperandeo, and both are out of print. Atlas has published books on DC wiring ( with an emphasis on wiring that matches their commercial products, but very good nonetheless) for decades and theirs is still in print. I think all will be more clear if you read up on DC wiring. Dave Nelson
That's the kind of metaphor my brain likes.
I have a lot of testing to do when I go down to the layout later this afternoon. I may try to do a short video with my phone, and upload it to YouTube or create an Instagram account and post the link. If I can't make that work, I'll take notes on what I'm seeing as I try all the suggestions.
I want to thank everybody for taking time from your day to answer my questions. It's appreciated.
I just had a thought. Would it help if I tried getting a DC power reading with a multi-meter. I've never tested for DC power, just AC circuits, but it can't be that hard to figure out.
I'd suggest setting up an isolated test track. I'm assuming you're using Atlas track since you mention using one of their booklets on track and wiring. Get one of the 9" terminal tracks and hook it up to one power pack's DC output. Maybe add a couple of straights on each side (either their sectional straights, or add a piece of flex track to either side).
Try the engines on the test track one at a time. Don't pick up the engine once it's on the track, just use the reverse switch on the power pack. If an engine works OK in both directions facing one way, then turn it 180 degrees and try it again. If they both work on the test track, then the error is in your wiring on the layout.
AjhallWould it help if I tried getting a DC power reading with a multi-meter. I've never tested for DC power, just AC circuits, but it can't be that hard to figure out.
If the goal is to check the reversing switch on the power pack, disconnect the two track feeders at the power pack terminals. Set your meter for DC voltage, at a setting more than 12 to 14 volts DC. Connect one lead to one of the power pack DC terminals, and the other lead to the other terminal. Move the power pack control handle/lever to the increasing speed position.
You should see a voltage value on the meter. It will either read a plus or minus value. Throw the reverse switch. The meter should now read the opposite voltage value (assuming you did not change the lever position). If it does, this means that the reversing switch is okay.
Ajhall I may try to do a short video with my phone, and upload it to YouTube
With an Iphone this is easy to do. I'm sure other smart phones are up to the task.
It never hurts to measure voltage when locos don't run. That said, I think the reversing switch is a red herring and the problem is the decoder needs a reset. Why?
You put the loco on the track and it runs in one direction.
Turn the loco 180 degrees and it doesn't go.
DCC decoders that need a reset can do weird stuff on DCC, why can't they do weird stuff on DC? Does the other loco actually do the same thing?
It should be easy to try the other locomotive if you haven't. That would pretty much determine if it's a wiring problem or a locomotive problem.
It takes an iron man to play with a toy iron horse.
The Bachmann loco he is using for the test has the brass wipers. What are the chances that both feeder wires from the wipers came off, on one side.
Although, it has happened to me, once, from an Ebay deal. Bought the loco as parts, ad said it didn't run, and that was the cause.
I dunno, one of those things that you wish you could be there, and see whats happening.
If both pickups fell off the loco on one side, it wouldn't run at all. That does not seem to be the issue at all. It's as if the motor simply can not turn one way - if it runs with one combination fo facing a certain way AND the direction switch set one way, if the loco is physcially tuend around AND the direction switch flipped, then the motor would be turning the same way it was in the running configuration. Since that fails, I can only guess the direction switch is broken and no power gets to the rails. However, with the loco physically turned around but the direction switch untouched - the loco should move in the same physical direction as the working mode, except that it will be running 'backwards' relative to the cab position. Since that also does not work, it seems to rule out the direction switch. This is definitely a mystery, it makes no sense electrically. Unless there are actually two problme shere, one being a failed direction switch int he pwoer pack, the other being something wrong internally in the loco. Easily verified with a cheap digital meter set to DC volts. I just don't knwo what could make a loco alone behave like that - only spin the motor in one direction, sure, lots of ways to mess up the internal wiring to make that happen. But turning the loco end for end on the rails AND flipping the direction switch does not change the direction the motor is trying to rotate.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Ya, I know, I thought of that after I left the house for a while. I was going to edit, but you already caught it.
Ajhall Now, with the switch on the power pack to the left ("forward"), and the rear of the loco facing clockwise (left), the loco travels clockwise. When I flip it around so the front of the train is facing clockwise (left), nothing happens. When I move the switch to the right, and the front is still facing clockwise, nothing happens. When I flip the loco again (rear facing left), it moves to the left (clockwise).
You say that with the switch on the power pack to the left (forward), the loco travels clockwise, then you flip it around and nothing happens.
How about trying this.
With the switch on the power pack to the left (forward), get the loco traveling clockwise, the flip it around and expect it do nothing. Slide the switch on the power pack to the right (reverse). Does anything happen? If not, slide the switch on the power pack back to the left (forward). Does anything happen?
I am just wondering if the directional switch is stuck.
Rich
Alton Junction
Remove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem.
Dave
Just be glad you don't have to press "2" for English.
http://www.youtube.com/watch?v=zQ_ALEdDUB8
http://www.youtube.com/watch?v=6hqFS1GZL4s
http://s73.photobucket.com/user/steemtrayn/media/MovingcoalontheDCM.mp4.html?sort=3&o=27
steemtrayn Remove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem.
I don't think it's been determined yet that it has a decoder in it. His Bachmann GP9 has "DCC On Board", but it comes out of the package with dummy plugs, in DC mode.
Unless he bought this from a sale site, and the previous owner installed a decoder. I asked him that in an earlier post, but I haven't gotten any answers.
I also asked him if the lights work in both direction, no answer yet.
EDIT: I'm probably wrong about this too, according to Bachmann, if this is a "DCC On Board", it's DCC out of the box. I'll just go back to my corner
There could be nothing wrong with the reversing, other than dirty oxidized contacts. I have had that happen to a MRC 1500 once in awhile if not used for a long period. The slide switch contacts build up oxidation and do not make contact when you slide them. I have had to slide them back and forth a few times to wear off the oxidation. I do that to all the slide switches on the unit and then they will work normal again. I believe that unit also has a momentum switch, that will also happen to it, do that to the slide switch also. It will also lose contact and make sure it is off when testing.
Do That on a test track....as has been suggested and don't worry about what direction the engine is facing, if the switch is working, the engine will go forward, slide the switch the other way and it should go in reverse. If it will not do that on the layout....you have a wiring problem or no power to some sections of Your track. If just using a terminal joiner and rail joiners for power distribution, anything is possible.
Good Luck!
Frank
Ya, I bought a "DCC On Board" 45-tonner recently, and it indeed has a decoder installed...a pretty basic one, but it works fine.
Some more questions / thoughts for the OP....
Although there is an NMRA standard for which rail is positive and which is negative, it doesn't really matter. You can wire it up either way and the engines will work fine.
Is it possible you accidently hooked up one of the track connection wires to the 12V DC accessory output instead of having both go to the 12V DC variable outputs? (12V variable output is controlled by the throttle; the 12V DC accessory outputs are a constant full 12 volts - for like lights or switches.) If I'm thinking this through correctly, if you say have one rail connected the positive 12V DC variable output, and the other rail to the negative of the 12V, you'd have a situation where if you have the reverse switch set one way, the engine would get variable positive DC from one rail, and the constant negative through the other, which should allow the engine to run. Hit the reverse switch, and now the variable DC is negative, and the other rail hooked up to the negative constant DC is negative too - so nothing happens.
You don't by chance have both power packs hooked up at the same time? If they're not wired in correctly, with double-pole / double-throw switches to choose which block is controlled by which power pack, it could be causing trouble.
I would get a couple of clip leads and a short piece of track. Connect the power pack output for the track to this short piece of track . Try running these engines on this short piece of track with no connection to any other track or equipment. Try the reverse switch . This should give you some idea if it is the engines or power pack issues. Do this with both packs connecting and trying one at time.
Ron High
steemtraynRemove the decoder and install a dummy plug. If it operates normally, then the decoder is the problem.
Do these Bachmann's have plugs? For the OP, some DCC ready locos came with a plug with a "dummy plug" that could be replaced by a DCC decoder plug. Not all OEM installed DCC decoders have plugs.
Maybe WHERE is a better question than WHY did he buy it. If at a local train store, they could try it on their display track and reset the decoder.
Phew! What I thought was a simple, even embarrassingly newbie a question is turning out to be challenging. To try to clarify, I managed to make a short video -- about a minute and a half, all I had the memory for -- demonstrating the problem and the power wiring set up. A couple of things to keep in mind:
https://youtu.be/Tn2oueQro1c