DC Supply track problem

[huttojb]

Hi gents.

This is my first post, my father-in-law has a model train set and he wants me to do the electronic behind it.

I'm an electronic engineer / software engineer so I know my stuff but I don;t want to re-invent the wheel if there is a solution out there.



Can anyone please point me in the correct area. Thankx

Jason

 

[cidchase]

Hi Jason,
Simplest answer: DCC (simple answer, maybe not so simple to implement.
You should have no problem.)
DC solution requires isolated track blocks with toggle switches
to change polarity on the tracks.

 

[huttojb]

Thanks.

I just went to reply and say I worked it out. Was thinking more about a turn wheel by using a DC Motor and decoder to monitor position.

I'm gonna be using a PIC controller and gonna put IR Tx/Rx to monitor train locations and change issolaters accordingly.

Thanks for the reply.

 

[fsm1000]

Use a doublepole double throw switch on the one leg of the wye.

 

[huttojb]

Can you buy isolated track blocks with toggle switches?

Can you give me a website where I can get my father-in-law to buy a couple?

Jason

 

[huttojb]

Just a quick question.

I'be been reading up on issolation blocks. This consist of cutting the +ve and -ve tracks and only powing the points between these blocks.

A couple of questions;

How big can the "GAP" be to restrict the train being de-railed?

 

[steamhead]

Hi,

There is no need for a gap, as such. There are insulating (plastic) rail joiners, with a little vertical tab that comes up to rail height. The track is held firmly but there is no electrical continuity.

Good luck!!!

 

[doctorwayne]

Is this supposed to be a wye? It looks to me like a track splitting into two tracks at a turnout. If so, connect one wire to each rail on the point side of the turnout (near the "arrowhead" for the "trains arriving"). No gaps or insulated rail joiners are needed.
By the way, welcome to the Gauge, Jason.

Wayne

 

[huttojb]

Hi Gent's

Thanks for your reply's, to be honest with you I haven't looked at a piece of track yet (I really should, at least I'd know what your talking about). At the moment I'm doing the software to monitor the trains at certain points and turning different tracks on accordingly.

Could anyone provide me a picture of this "insulating (plastic) rail joiners". I don't think my father-in-law has these so I'll have to get him to buy some, can you order over the internet?

Jason.

 

[josh0351]

I believe this tutorial should assist your quest: http://www.nmra.org/beginner/wiring.html

 

[huttojb]

Can someone take a Picture of 1 and post it here. I understand what they are used for and understand the reasons, I'm not a model railway person, I'm just writting software for my father-in-law.

Thank you all for your help

 

[cidchase]

I think these are the soft Atlas ones I tried one time and one time only!! wall1
Seems like I read about some stiffer plastic one but have not seen them.
I hope someone can post more about these.

 

[huttojb]

OH? I see now.

So you put these in between the 2 normal tracks. I was under the impression it's a track with a plastic bit within it?

Thank you,

jason

 

[fsm1000]

Jason, it is just a dpdt switch. Like a light switch that you use to turn on and off only it can change the polarity of the rails like a reversing switch.

As for a gap, it needs only be about as thick as a fingernail. Nothing huge at all.
I use a thin piece of wood for a couple of reasons. One I can glue it in place. Two it does flex a minute amount allowing for a wee bit of expansion in my rails. Three I can file it down easily.

But those rails joiners will work for you as well.

 

[YmeBP]

Jason, it is just a dpdt switch. Like a light switch that you use to turn on and off only it can change the polarity of the rails like a reversing switch.

As for a gap, it needs only be about as thick as a fingernail. Nothing huge at all.
I use a thin piece of wood for a couple of reasons. One I can glue it in place. Two it does flex a minute amount allowing for a wee bit of expansion in my rails. Three I can file it down easily.

But those rails joiners will work for you as well.

I am curious i've read about the gappers etc. But doesn't the wheel span both sections when it rolls over? Wouldn't that in essence act as a joiner and short the whole thing?

 

[Ralph]

Nope. No shorts occur. I've used the insulated rail joiners and have also simply cut gaps like fsm1000. Both methods work just fine.
Ralph

 

[60103]

If the wheels shorts across the gap, you've done something wrong. The direction switches are supposed to be aligned in the same direction before you cross the gap. The gap is there for when the direction switch, track switch or something else isn't aligned.
Example: all rail switch in a loop. If the switch is set for the siding, current will come around one rail and cross to the other through the frog and pont of the switch; the gap keeps the current from coming to the frog. If you run a train at the switch the wrong way, you get a short and the train stops dead instead of continuing on and creating havok.

 

[YmeBP]

Nope. No shorts occur. I've used the insulated rail joiners and have also simply cut gaps like fsm1000. Both methods work just fine.
Ralph

o.k. i think i understand i have a couple wiring books and one more form atlas on the way. I have a couple loops setup and as soon as i get my cleaning situation handled i'd like to step up to turnouts etc. on my layout.

Do you have a picture of a properly gapped track section maybe a turnout?

 

[steamhead]

Actually, the gap is to prevent a short from ocurring (at least in "live" frog turnouts). If you look at it closely, the frog would "join" the inner and the outer rails causing a short.

I use the "stiffer" plastic rail joiners from Peco. The Atlas ones are altogether too "wiggly", and some have the gap tab missing...!!!