Modelling LU track

[Deleted]

Some months ago, there was a question on this board about the availability of components to model LU conductor rails.

Issue 170 of Model Railway Journal has just reached Australia, and it contains a detailed article on modelling conductor rails. It deals with SR three-rail track, but the components and techniques are equally applicable to LU four-rail.

Apparently Exactoscale make dead scale 4mm conductor rail, insulator supports (in both SR and LU designs), and castings for the ramps used by LU at crossings and other ends of conductor rails.

It looks to be very fiddly work involving tiny parts, but the photos show that superb results can be obtained.

Hope this is helpful to someone.

[markextube]

Hi yes iv'e built a small layout and intending to build a larger layout based on the LUL 4th rail system.

A company here called Peco make the plastic conductor rail chairs which then slide onto Peco code 60 rail. Then after drilling holes in the sleepers the rails can be glued into place. Very realistic looking.

I also converted the trains with miniture pick up shoes to pick up the power from centre/fourth rail instead of the running rails. Works very well after a bit of adjusting. Though wiring all of the currents rails are a bit of a nightmare especially at junctions but worth it.

[mandgc]

Working Model Third and Fourth Rails -

The next step is to install working Track Circuits in the Running Rails ! (A simpler method would be to use the third and fourth rails for the track circuits. :-)

[ongarparknride]

markextube, Please could you post a bit more detail about how you amended the bogies to collect from the third and fourth rails? I'm sure this gets "fiddly", but as an alternative to DCC type control, a third rail connection opens up directional lighting, plus coach lighting if inter coach rakes can be wired. With fourth rail connection, you could not only have "proper" track occupation circuitry, but Rule The World :-)

If you could share a bit more of your personal modelling experiences on this subject, I'd be much obliged.


Cheers,
OngarParkNRide

[Deleted]

if you was going to install a track circuit lul uses capacitors in its convential track circuits but when i was a apprentice we found that resistors are far better but get extremly hot when the shunt (short circuit) is applied across the track

for a basic track circuit hand drawn by me and yes im not very good please see

aetearlscourt.fotopic.net/p39609756.html

[Deleted]

aetearlscourt said:

if you was going to install a track circuit lul uses capacitors in its convential track circuits but when i was a apprentice we found that resistors are far better but get extremly hot when the shunt (short circuit) is applied across the track

for a basic track circuit hand drawn by me and yes im not very good please see

aetearlscourt.fotopic.net/p39609756.html

I was told this once but have since forgot - what do the acronyms NX and BX stand for?

I am assuming that the left-hand side of the diagram is the feed that energises the track circuit, and that the right-hand side of the diagram is the pickup that detects the state of the track circuit. If that is the case, what type of fail-safe contact pattern does the relay use to indicate a potentially occupied track circuit?

[Deleted]

bx and nx indicate that the feed is supplied by a A.C supply and then b and n indicate its fed from a D.C supply the number after the letters indicates the actual voltage

the track circuit relay (TR T= Track R=Relay) has 2 coils in it to energise it thus needing 2 supplys one comes directly from the track the R coil and the other comes from a busbar directly fed the Q coil this is not always the case though with the Q coil tracks which are after signals (replacing tracks) are fed around a ON contact (only makes when head is fully up) of the trainstop to make sure the trainstop is mechanicaly sounds so it checks that the trainstop comes to the fully ON position after each and every train. if either of the coils as no feed on it then the TR will stay de-energised this is a TR from Parsons Green as u can see the coils are in the middle of the relay itself and the relay is in its energised positionhttp://aetearlscourt.fotopic.net/p15538927.html

if the any of the wires break (open circuit) or something is shorting the rails (short circuit) then the R coil will not have a feed on it thus keeping the TR de-energised