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How to Independently Wire Two Yards to SPDTs

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  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Friday, November 30, 2018 6:22 AM

 That does not make the direction independent on each of those sections, it just allows you to cut power and park a train on any of those tracks with a toggle between the raila nd the power, which is as much as you can do with  SPDT.

 But as I said way back, there's little point having a center off directional DPDT toggle for each yard/siding, there's generally no need to change the direction on just a siding but not the connected main - in fact if the siding and main are set to opposite directions and metal wheels or a powered loco or lighted car crosses the gaps, it's a short.

                                                 --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
    December 2015
  • From: Shenandoah Valley
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Posted by BigDaddy on Friday, November 30, 2018 7:27 AM

rrinker
in fact if the siding and main are set to opposite directions and metal wheels or a powered loco or lighted car crosses the gaps, it's a short.

Another reason to go DCC,

Henry  running and ducking Big SmileDevil

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Friday, November 30, 2018 1:24 PM

diagram from HOmainline

  1. south yard SPDT center terminal needs to be connected to gapped south rail (this is different from north yard SPDT.
  2. based on diagram, mainline DPDT has no function
  3. if all mainline tracks are connected to the mainline DPDT the same way, i don't know how direction is controlled on mainline

 

if mainline DPDT is intended to control direction on all mainline and yard tracks corner terminals should be "cross wired" as shown in diagram below and connections A and F connected to top 2 terminals that motor is connected to below, along with any other mainline track connections

greg - Philadelphia & Reading / Reading

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Friday, November 30, 2018 1:40 PM

 Based on that drawing - the mainline DPDT only functions as a terminal strip to join the wires.

Also missing a wire from the South Yard SPDT to the South Yard isolated rail.

                                         --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
    November 2017
  • 153 posts
Posted by HOmainline on Friday, November 30, 2018 3:56 PM

rrinker

 Based on that drawing - the mainline DPDT only functions as a terminal strip to join the wires.

Also missing a wire from the South Yard SPDT to the South Yard isolated rail.

                                         --Randy

 

 

Randy,

On your first point above, more comments coming soon.

As to your second: I'll make that correction.  Thanks!

 

Kerry

  • Member since
    November 2017
  • 153 posts
Posted by HOmainline on Friday, November 30, 2018 4:02 PM

gregc

diagram from HOmainline

  1. south yard SPDT center terminal needs to be connected to gapped south rail (this is different from north yard SPDT.
  2. based on diagram, mainline DPDT has no function
  3. if all mainline tracks are connected to the mainline DPDT the same way, i don't know how direction is controlled on mainline

 

if mainline DPDT is intended to control direction on all mainline and yard tracks corner terminals should be "cross wired" as shown in diagram below and connections A and F connected to top 2 terminals that motor is connected to below, along with any other mainline track connections

 

 

Greg,

1. Great!  That's what I'm looking for.   I'll then connect the south yard's SPDT center lug to the gapped south rail.

2. I didn't bother to show the cross wiring - or the wiring for the other four lugs - on the mainline DPDT because I mentioned a few times before that it - and the reverse loop DPDT - have been functioning flawlessly for two years now (and continue to do so) and because it's also not the (direct) focus of my question, though, of course, it's critical.

Granted, however, without showing the cross and top & bottom lug wires in my diagram, it is misleading.  Guilty as charged!  Oops - Sign

So, both DPDTs are cross-wired, and all six lugs on each are properly wired for mainline and reverse operations.

3. See no. 2

Other than that and Randy's south yard/SPDT correction, how's it look?  Ready to go?

Kerry

  • Member since
    December 2015
  • From: Shenandoah Valley
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Posted by BigDaddy on Saturday, December 1, 2018 7:04 AM

I think so.

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    November 2017
  • 153 posts
Posted by HOmainline on Saturday, December 1, 2018 1:51 PM

BigDaddy

I think so.

 

 
Henry,
 
Stand by.  But off the tracks!  Wink

Kerry

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Saturday, December 1, 2018 3:15 PM

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    October 2017
  • 104 posts
Posted by GNMT76 on Sunday, December 16, 2018 11:15 AM

Gentlemen,

Thanks to all who contributed to addressing the question here. Problem solved!

Kerry

  • Member since
    January 2006
  • From: Northeast OH
  • 2,268 posts
Posted by NeO6874 on Monday, December 17, 2018 5:07 AM

GNMT76

Gentlemen,

Thanks to all who contributed to addressing the question here. Problem solved!

 

 

What'd you end up doing?

-Dan

Builder of Bowser steam! Railimages Site

  • Member since
    October 2017
  • 104 posts
Posted by GNMT76 on Monday, December 17, 2018 11:30 AM

Dan,

Well, I took up skydiving instead of messing with all those wires!  Big Smile

Actually, this simple solution:

- center lug of each SPDT wired to its respective yard rail

- top lug of north yard SPDT wired to bottom lug of the south yard SPDT and

- bottom lug of south yard SPDT wired to the negative bus

Works like a charm!

Kerry

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