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Pls recommend a "reversing unit"

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  • Member since
    November 2007
  • From: auburn,in
  • 113 posts
Pls recommend a "reversing unit"
Posted by wheeler on Wednesday, January 21, 2009 10:15 PM

Track mods and enhancements  enabled me to add a "Wye". It cleared up a bad area and i'm kind of excited about it. "BUT' I am now in need of a reversing unit. In light of 2 past bad purchases, I am going to bore/ask on here for something that "just works"

I am pretty sure I want an electronic unit, as they act faster. I am HO scale, NCE powercab running steam and early diesels and 40-50 foot cars.

Furthermore- I am curious as to "HOW" the reversers actually work. Does the unit detect a minute"short" as the wheels connect thru the track(s) out of phase/polarity, "Then" swap via an SCR (or similar) once it is energised?

 I am looking for links, opinions, and prices

  • Member since
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  • From: Gahanna, Ohio
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Posted by jbinkley60 on Thursday, January 22, 2009 3:40 AM

wheeler

Track mods and enhancements  enabled me to add a "Wye". It cleared up a bad area and i'm kind of excited about it. "BUT' I am now in need of a reversing unit. In light of 2 past bad purchases, I am going to bore/ask on here for something that "just works"

I am pretty sure I want an electronic unit, as they act faster. I am HO scale, NCE powercab running steam and early diesels and 40-50 foot cars.

Furthermore- I am curious as to "HOW" the reversers actually work. Does the unit detect a minute"short" as the wheels connect thru the track(s) out of phase/polarity, "Then" swap via an SCR (or similar) once it is energised?

 I am looking for links, opinions, and prices

DC or DCC ?  Here's my recommendation (if it is DCC)

http://www.dccspecialties.com/products/powershield_x.htm  -  The PSX-AR model.

Here's the manual.

http://www.dccspecialties.com/products/pdf/man_psxar.pdf

And a review done by Model Railroader Magazine

http://www.dccspecialties.com/products/psx_mrreview.htm

 

 

Engineer Jeff NS Nut
Visit my layout at: http://www.thebinks.com/trains/

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  • From: Bedford, MA, USA
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Posted by MisterBeasley on Thursday, January 22, 2009 6:19 AM

I agree completely.  The DCC Specialties products are a spinoff from Tony's Trains.  I've got the earlier model of Tony's reverser unit.  It's all solid-state, which is faster and more reliable.

You basically have the theory right, too.  When the unit senses a short (or polarity mismatch across the insulator) it flips the polarity of the track in the reversing section.  Since DCC does not depend on polarity for train direction or passing control information, the engine doesn't see anything different.  One problem this does present, though, is that you can only "bridge" one end of the reverse section at a time, but with a wye that should never be a problem.

Incidentally, I took my advice to get the Tony's reverser from this forum.

It takes an iron man to play with a toy iron horse. 

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Thursday, January 22, 2009 6:34 AM

 Yes, that's exactly how they work - they detect the short and the reverse the polarity of the track they feed. In DCC you change the polarity of the loop, wheras the typical way in DC is to change the polarity of the main that the train is about to enter. The reason being that the the DCC square wave signal and power, the 'polarity' (really, phase) of the signal has nothign to do with the direction the train will move in. You can hook a DPDT switch between your DCC system and track and flip it back and forth all day long and the train will keep moving forward if commanded to move forward.

 As for the choice of device, I originally bought into the "oh yeah solid state is definitely better" until I happened to start helping someone build their layout. Even with ultra-low current N scale locos, his PM42 breakers and AR1 autoreversers from Digitrax work just perfectly. I totally expected the locos to jerk back and forth or something when crossing the reversing section, since that seems to be the urban legend surrounding electromechanical devices. But there are not hesitations at the reverse loop - contrary to popular opinion, the relay flips PLENTY fast enough, even when the train is crawling. The PM42 is only suitable for Digitrax systems since to change the default trip current you need a Digitrax throttle to program it, but the AR1 has no programming, no jumpers to solder for adjustment. Instead there is a potentiometer to adjust the sensitivity. Works with any DCC system, and is very inexpensive. For a Digitrax user, the advantage of the PM42 is that it already provides feedback information as to the status of each section, and has manual control over the power for each section - again via Loconet so it will only work with a Digitrax system (or Uhlehnbrock Intellibox which is Loconet compatible). AR1 has no such specific connections, just power in from the bus and power out to the isolated loop track.

                                                            --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • From: Gahanna, Ohio
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Posted by jbinkley60 on Thursday, January 22, 2009 8:02 AM

I concur with Randy's comments.  I will note that the PSX series provides feedback for Digitrax Loconet, NCE CabBus and Lenz (ExpresNet) systems.

 

Engineer Jeff NS Nut
Visit my layout at: http://www.thebinks.com/trains/

  • Member since
    December 2004
  • From: Bedford, MA, USA
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Posted by MisterBeasley on Thursday, January 22, 2009 12:03 PM

davidmbedard
 We will only recommend if you promise to read the manual before you use it......

Aw, that takes all the fun out of it...

(Seriously, it is a good idea, particularly when the manual is only a page or two.)

Which of these units provides automatic control for flipping turnouts as the train exits the loop?  The OP (and others) might be interested in that feature.

It takes an iron man to play with a toy iron horse. 

  • Member since
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  • From: Fredericksburg, VA
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Posted by Bill54 on Thursday, January 22, 2009 8:12 PM

Another vote for Tony's Train  (DCC Specialties) PSX-AR.  I have two on my layout and although they say to offset the gap by about 1/8" I just isolated the section at each turnout with Atlas plastic rail connectors.

I have had no problems with either sound trains or regular non-sound units.  They work great.  There is no hesitation or blinking of the headlights that you might think.  When the loco crosses the gap it's like nothing ever happened.  It just keeps on truckin, excuse the expression!

Even the older units that Tony's sold work as good as the new ones that DCC specialties is currently putting out.  The benefits of the new units is they can switch the turnouts automatically if you desire.

Bill

As my Mom always says...Where there's a will there's a way!
  • Member since
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  • From: Reading, PA
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Posted by rrinker on Friday, January 23, 2009 7:31 AM

jbinkley60

I concur with Randy's comments.  I will note that the PSX series provides feedback for Digitrax Loconet, NCE CabBus and Lenz (ExpresNet) systems.

 

 ONLY if you hook it up to a stationary feedback unit for one of those systems. They do NOT connect directly to any DCC system for feedback, it's just an output that it turns on and off to indicate status of the connected track. You could hook an LED to it (although they provide another connection for that as well). For Digitrax you'd hook it to a DS64 or DS54 or LocoIO port configured for input, for NCE you'd have to connect it to an AIU01, for Lenz you'd need an LR101 Feedback Encoder.

 This is a bit of tricky marketing on their part - it has a CONNECTION for feedback for any DCC system that has input modules available (which is why they leave out CVP) and so has the capability for feedback - with extra hardware. Same thing for the Hares and Wabbits with feedback - none of those conencts directly to any DCC system, it only can do so via one of the modules listed above, depending on which brand of DCC you have.

                                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • From: Southwest US
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Posted by tomikawaTT on Friday, January 23, 2009 10:34 PM

A couple of questions of my own:

  • Is the wye a simple stub-ended variety?
  • Does the device that actuates the points at that stub end have unused DPDT 'break before make' contacts?

 

If you answered YES to both questions, all you need to do is wire the rails to the switch machine (or whatever) contacts.  When the route selection changes, the wye stub rails will be connected to the proper approach rails - totally automatic, and totally foolproof.  This works for both analog DC and DCC.

KISS rules.

Chuck (Modeling Central Japan in September, 1964 - with lots of switchpoint actuator contact electricals)

  • Member since
    November 2007
  • From: auburn,in
  • 113 posts
Posted by wheeler on Saturday, January 24, 2009 12:04 PM

I bought (ordered) the PSX-AR. I also found the correct (for me) PCP panel for "MY" remote operations.

Hopefully later this week it will all show up!

  • Member since
    November 2007
  • From: auburn,in
  • 113 posts
Posted by wheeler on Sunday, January 25, 2009 10:56 AM

Turning the engine on the wye may not be as exciting as using a turntable, but cleans up an industrial area, and saves a lot of real estate at the same time (vs a TT)

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