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Locos going only right-to-left...no reverse

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  • Member since
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  • From: NW Pa Snow-belt.
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Posted by ricktrains4824 on Wednesday, March 7, 2018 10:16 PM

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.

  • Member since
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  • From: SE. WI.
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Posted by mbinsewi on Wednesday, March 7, 2018 10:00 PM

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?

Mike.

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.

  • Member since
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  • From: Shenandoah Valley
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Posted by BigDaddy on Wednesday, March 7, 2018 9:20 PM

dknelson
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.

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

  • Member since
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  • From: Milwaukee WI (Fox Point)
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Posted by dknelson on Wednesday, March 7, 2018 9:06 PM

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
 
  • Member since
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  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Wednesday, March 7, 2018 8:22 PM

To confirm your track wiring from the power pack try a non DCC locomotive.  If a non DCC locomotive works correctly from the Forward/Reverse switch on the power pack the problem is in the DCC locomotive, most likely not programmed to operate in DC mode or the decoder is corrupt.
 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
  • Member since
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Posted by Ajhall on Wednesday, March 7, 2018 7:52 PM

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.

  • Member since
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  • From: SE. WI.
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Posted by mbinsewi on Wednesday, March 7, 2018 3:31 PM

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 ? Confused  Or do you try just one power pack at a time?

AND, are you running both locos? together, or trying each one seperately?

Mike.

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Posted by selector on Wednesday, March 7, 2018 1:55 PM

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?

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Posted by maxman on Wednesday, March 7, 2018 1:51 PM

dknelson
Mel 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.

  • Member since
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  • From: Milwaukee WI (Fox Point)
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Posted by dknelson on Wednesday, March 7, 2018 1:14 PM

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

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Wednesday, March 7, 2018 12:27 PM

The reversing switches don’t work?
 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
 
  • Member since
    January 2016
  • 20 posts
Locos going only right-to-left...no reverse
Posted by Ajhall on Wednesday, March 7, 2018 12:20 PM

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? 

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