Controlling Colour Light Signals & Point Motors.

[mattrose]

Hi,

I am currently making a OO gauge modern image layout in the UK. I am using 'gaugemaster PM1 motors' and plan to use Berko or Traintronics for 3 aspect colour light signals.

I would ideally like to use a 'MODRATEC' lever frame to control these but how can I control a 3 aspect signal with 1 lever? How would these be wired?

And how will I need to wire up the points to be controlled with a lever from the frame?

Thanks. Matt

[modadmin]

Hello Matt,

To operate double-solenoid point motors from a lever, look at our Point Motor Pulser units: https://MODRATEC.com/cart/index.php?mai ... x&cPath=26

When it comes to 3-aspect signals, you need to decide the conditions under which the signal will show either yellow or green. When the signal lever is normal, naturally enough this will drive the red aspect of the signal. When the lever is pulled, the signal may be red, yellow or green, depending on conditions. It will be red if the section ahead is occupied (and you are determining track occupation). It will be yellow if there is one clear section ahead (detecting occupancy) or if the next signal is red or perhaps diverging. It will be green if there are two clear sections ahead or if the next signal is not red/diverge.

[mattrose]

How will the signal know if the section ahead is clear?

[modadmin]

To detect the presence of a train, there are circuits available for this. I would suggest looking at the offerings at MERG. http://merg.org.uk

[mattrose]

To operate double-solenoid point motors from a lever, look at our Point Motor Pulser units: https://MODRATEC.com/cart/index.php?mai ... x&cPath=26

Are there other ways to move the trigger the points (fitted with PM1 by gaugemaster)

[modadmin]

The main issue with double-solenoid point motors is that they are high current devices that require just a short pulse of high current to make them operate. They cannot be powered continuously as they will very quickly burn out.

In order to operate these from a simple lever, one option is "passing contacts". With this method, as the lever moves from one end of its travel to the other, it briefly causes power to flow to each coil of the point motor in turn. Although MODRATEC does not currently provide such a unit, it might be possible to mechanically link a lever to operate a seperate passing contact switch.

(If using passing contact switches for point motors, it is always recommended to power these using a CDU (Capacitor Discharge Unit).)

The other option involves a method of generating short pulses of current directed to the appropriate coil depending on whether a lever is normal or pulled. That is what our Point Motor Pulser does. It is also a much gentler way of operating point motors, similar in that respect to the use of a CDU. You may also like to refer to our article about this topic: https://MODRATEC.com/mud_points.php

[mattrose]

I was planning on pulling the levers to the right setup and then operating a CDU but was unsure if this would work.

Also how many points can a pulser unit do at once.


Thanks. Matt

[modadmin]

Our auxiliary switch units not have a high enough current rating to route current directly to solenoids. However, you could interpose relays to switch the coil current if you wanted to go that way.

Each of the 6 channels of our Point Motor Pulser can almost certainly operate a pair of point motors - a crossover for instance. I can't promise that only because factors such as operating voltage, weight and length of connecting wires, and tightness of points can all have an effect.

By the way, have you considered operating the points using our wire-in-tube system? It's very reliable and affordable, and easy to set up.

[mattrose]

How does wire-in-tube work?

Is it connected directly to the lever and to the point?

[modadmin]

Matt,

Please refer to this section in the MODRATEC Shop:

https://MODRATEC.com/cart/index.php?mai ... ex&cPath=2

A wire is directed through a tube directly from a lever to one or more points. At the points, a simple slipping-clutch mechanism joins the wire to the points such that the points are fully operated while permitting full travel of the lever. Very simple to configure, and very affordable.