Bernard Gudgin and Michael Watts are experienced teachers and trainers. They have several decades of modelling and exhibition experience across the gauges from T (scale 1:480) to 16mm live-steam (scale 1:19), as well as narrow-gauge. They are often seen at exhibitions where they provide free advice to newcomers and returnees under the brand name of Oxford TRAINing.
Even on a small layout you may want to move more than one locomotive at a time. For example, you may want to shunt in a goods yard while a passenger train arrives at a station. This is most easily achieved using something called Cab Control.
It follows exactly the same principles of wiring and switching that we have already described but it gives more flexibility in operating your layout, but you do need two controllers (cabs) – one to drive each locomotive – and this is then called two-cab control. The operation of your points and their power supply remains exactly the same as with a single controller.
You can have cab control for any number of locomotives all operating at the same time, but the switches become a bit more complicated and maybe your layout is not that big – and you have not got enough hands!
We have previously described how each of the separate track sections of your layout is powered via switches – either on or off. Each track section has its own switch between the (one) controller and its section. As a result you can apply power to only those sections that form the route for your train. Any locomotives on other sections remain electrically isolated and hence unpowered. This is the situation for one controller – that is one-cab control.
If you want to operate two locomotives at the same time, each on different track sections, you will need to add a second controller so that you now have two cabs – hence the term two-cab control.
Each controller operates one locomotive on its route over sections of track selected by switches. But you do now need to change each of the section switches to a different type – from single-pole on/off type to single-pole double-throw centre-off type.
These are the same physical size but the dolly now has three positions. This gives you the additional facility of a centre-off position when no track section is connected and so is electrically completely isolated from either of the two cabs – useful when checking wiring, and valuable to completely isolate a locomotive on a particular track section.
These switches are the same physical size as before, but have three contacts on the underside, and cost very little extra. You will be able to upgrade your previous control panel to two-cab control fairly easily by just replacing the track section switches, adding a second controller and a bit more wiring.
For the full article, see September’s edition of Modelling – available now!
For a complete list of stockists and how to get your copy, visit: www.railwaymagazinemodelling.co.uk/distributors