How do you power your long 12V track?

[kzv]

Hi,

I've just found all my 12V lego stuff and put together a track which is about 15 meters (50 feet) long.

Since it's one "loop" with tracks I only use one transformer (7864). When the train reach the "far end" (longest distance from the transformer), it hardly move forward :-(

Have any of you tried this length of tracks before with any luck?

Tried to clean the tracks and the motor, but still the same problem.

rgds

Kjetil

[coaster]

I've never used the 12V tracks, but we have a similar problem with the 9V tracks. What's happening is you get a voltage drop across the rails, so on that far side, you're not really seeing 12V, probably more like 3 or 4V if that. It's not a cleanliness issue; it's simply the nature of the rail material. We just add additional transformers on the far side, and that solve the problem.

[EdwinWesterhof]

I'am using 12 volt rails myself and i have made some more connections with the same trafo just see to it that you connect the same wire on the same side and it while work fine. If you connect the wires the wrong way, no problem but the train wil not drive. If you are going to use more then 2 trains you wil need more power. I have split my tracks in 3 separate sections and every section has its own trafo, this way there are never more than 2 trains on a section. The big blue trafo with the studs on top have a better power output then the gray ones.

[bricks n bolts]

I'am using 12 volt rails myself and i have made some more connections with the same trafo just see to it that you connect the same wire on the same side and it while work fine. If you connect the wires the wrong way, no problem but the train wil not drive. If you are going to use more then 2 trains you wil need more power. I have split my tracks in 3 separate sections and every section has its own trafo, this way there are never more than 2 trains on a section. The big blue trafo with the studs on top have a better power output then the gray ones.

Yes, that works for me too.

[PeteM]

When you say split - are the three sections electrically isolated from each other, or have you just hitched up the transformers at various points around the layout to roughly equalise the voltage?

I've bought a couple of extra transformers over the past few years with the vague intention of experimenting when/if I even get the time, but I'm far from familiar with electrics and don't really want to blow anything up - not least as so much of the 12v stuff is so expensive these days...!

[dr_spock]

Each section would be isolated into "blocks" and controled by its own transformer is one way of doing it.

Another way is to run another set of wires from your transformer to the track in the section with problem. Be sure the wires are connected to the proper rail. This way you can control with one transformer. This is done some times in scaled model railroading. Assuming it'll work with LEGO too. The copper wires would have less resistance and voltage won't be lost due to track connections, joiners, etc. along the way.

[Q3671]

dr spock has a point and use a wire with 1,5 mm² thickness.

isolated into "blocks" and controled by its own transformer thats in real live the same.

[harnbak]

For related comments, please see here:

http://www.eurobricks.com/forum/index.php?showtopic=58107&st=25

http://www.eurobricks.com/forum/index.php?showtopic=68603

http://www.eurobricks.com/forum/index.php?showtopic=62019#entry1116259

[kzv]

I'am using 12 volt rails myself and i have made some more connections with the same trafo just see to it that you connect the same wire on the same side and it while work fine. If you connect the wires the wrong way, no problem but the train wil not drive. If you are going to use more then 2 trains you wil need more power. I have split my tracks in 3 separate sections and every section has its own trafo, this way there are never more than 2 trains on a section. The big blue trafo with the studs on top have a better power output then the gray ones.

Very well! I'll try that :-D

Thanx!

[Brickthus]

When 12V trains were still current products, there was a spares pack with a long wire (3m) and plugs.

The advice was to use this to make more connections to the track for long runs, in addition to its uses for point and signal control.

Other models railways are similar. I have books that advise each section to be powered separately with wires from the control panel.

The same is true of Scalextric. The older system had jump leads designed for long tracks. The idea is to connect one end to the section of track next to where the transformer is connected, then connect the other end to the far side of the circuit.

So there's nothing unique to LEGO in voltage drops!

Mark

[kzv]

I'am using 12 volt rails myself and i have made some more connections with the same trafo just see to it that you connect the same wire on the same side and it while work fine. If you connect the wires the wrong way, no problem but the train wil not drive. If you are going to use more then 2 trains you wil need more power. I have split my tracks in 3 separate sections and every section has its own trafo, this way there are never more than 2 trains on a section. The big blue trafo with the studs on top have a better power output then the gray ones.

One thing I don't understand is how to make several isolated sections, but still be able to let the train go from one section to another (without modifying the original parts)... Any hints?

[EdwinWesterhof]

At first i isolated the sections with just some tape, but that was not always a good isolation, so i decided to modify some section, bij cutting the iron rails in half. the best place to do this is in the middel of the iron rails. only cut deep enough so that the iron strip is in 2 but not the plastic.

Lol never noticed the oxidation, used a very old rusty saw to make this cut, don't make the same mistake

The isolation is only needed when you use multiple transformers. It is not needed if you connect your rails on several places to the same transformer.

If you don't want to modify your tracks you could also use Train, Track 12V Conducting Rail Straight for 12v Signal with Rail Interruption in the Middle

http://alpha.brickli...age?P=3242d#T=C

But this only interrupts on one side, you can use this, but only if you know what is + and - on your track and you use the interruption on the + side. But it is better to isolate both tracks.

Because if you drive the other way + and - switch and then there is no isolation on the + side.

Edited January 14, 2016 by EdwinWesterhof

[freestorm]

You can use two interupted tracks, so you will not have short-circuit in the case your two loops are not at the same polarity

But when you want to run your train between the two loops, you need to have both transformers at the same polarity.

Otherwise your train will go back when the motor touch the second loop. :-)

I think you need to be aware of shortcut inside the motor when you go to the second loop.

It's not good for the motor to have the front in the first loop, and the back in the second loop

If your loops are reversed, your are going to have a short-circuit inside the motor.

It's better to have a small portion of track without electricity, so the motor can't touch both loops at the same time.

But you can't run slowly, because it will stop in this small portion.

I used this system to automaticly reverse the polarity of my tracks, to make a reverse loop without short-circuit the track or the motor.

PS: I hope you understand what I mean, English is not my native language

[LEGO Train 12 Volts]

You can refresh the signal with further connections on the far side of the loop:

[kzv]

At first i isolated the sections with just some tape, but that was not always a good isolation, so i decided to modify some section, bij cutting the iron rails in half. the best place to do this is in the middel of the iron rails. only cut deep enough so that the iron strip is in 2 but not the plastic.

OK, that's my initial idea as well...I'll try that!

You can use two interupted tracks, so you will not have short-circuit in the case your two loops are not at the same polarity

But when you want to run your train between the two loops, you need to have both transformers at the same polarity.

I'll have a look a this solution too!

PS: I hope you understand what I mean, English is not my native language

No worries! I perfectly understood you message ;-) (I'm not English either :-D)

You can refresh the signal with further connections on the far side of the loop:

Yupp, done that and it helped a little. Think I have to clean the tracks again, their very shiny, but still everything is a little bit "staccato". Any hints of ways to clean the track?

[EdwinWesterhof]

For cleaning my tracks i made this.

this way its not so much work , i use some vinegar on it. I have the vinegar in a old aftershave bottle to cover the smell.

And when i'm not lazy i steal a scourer (colored sponge with a green top, do not know how they are called in English) from my wife with just some water and soap. This helps to get the black tan of the rails and most corrosion.

But since i use my car its not needed to do it often. So i would recommend building a cleaning car.

[LEGO Train 12 Volts]

For cleaning my tracks i made this.

Great idea!

[bricks n bolts]

Great idea!

Yes, I must to do something like that.