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· Registered
57 Posts
Discussion Starter · #1 ·
I have come across a problem with the output from the Hornby select controller. I was using a gaugemaster Combi DC controller on a small layout and have now changed to DCC. The 16 DC AUX output on this controller does not have enough power to fire Peco point motors on Peco points, its OK with 2 surface mounted Hornby points & motors. Wired the Gaugemaster back up and they worked fine.

· DT
5,345 Posts
The Hornby Select has only 1 amp to play with. Some power goes to the track and not much is left for anything else.

Peco point motors work best at about 2 amps.

So the accessory output is not suitable for points.

Note, the Hornby point decoders use a capacitor discharge system fed from power from the track itself.

· Registered
219 Posts
When I was considering changing to DCC and discussing it at my local model shop, I was advised to carry on using DC power for the point motors. I'm running a "select" as well and haven't bothered even trying out the Aux point. The two systems run well together, and as it was pointed out to me, I can use the speed knob on the DC controller to control the turntable (when I get one!). The other advantage is that you haven't got the expense of accessory decoders.

· Registered
5,598 Posts
very sensible approach Mike, OK in the future you loose the advantage of computer control signalling and route control, or you could consider mix and match. If you have a couple of routes you only use stationary decoders for the critical turnouts that determine the route. Another alternative is the Tortoise and Hare combination which gives you semi automated route selection at low cost.
You get 100% for effort in my book, and I'm sure that most of the other contributors are following your efforts very closely.

· Premium Member
2,740 Posts
You can boost power to the Select to 4 amps.

This has been fully discussed on the Hornby Forum and several solutions have been offered. We could copy and paste them here. Points with a strong "click" or point springs do require more powerful point motors. Maybe this is the reason why a lot of continental and american points have soft springs.

Warley MRC maintains a seperately powered "normal" circuit for layout accessories and this seems to be a preferred option. It is really down to how many accessories you are planning to operate. Now at Warley every point on the circuit has its own capacitor also! This may be considered overkill however large numbers of points are switched at a time and Warley MRC have to consider public safety and cannot put too much power through their accesory circuit.

Hornby also have to consider public safety of course!

We are not in the 1920's when you could put 240v through your Hornby train set!

I don't think Hornby have a hidden agenda to monopolise DCC. The new Hornby point motors do seem to use less power than before and maybe Hornby simply recognised this issue during development and came up with a new point motor.

Here is the info from the Hornby Forum:-


By Dave
Mon 15 Jan 2007 15:01
So one CDU can be used for as many points as one a layout, you just have to run the wires from the various points into it, I presume.

(Excuse me ignorance here but electrics was never one of my strong points).
Re: DCC Power

By Philip
Tue 16 Jan 2007 11:54
That's right. You connect the input of the CDU to the Select unit accessory power connectors (observing the correct polarity). You then connect the negative output from the CDU to the black wired connection on each of your points motors (i.e. connect all black wires from the points motors together and link these back to the negative connection on the CDU). Then take the positive connection from the CDU to the brown wired connection on your bank of Hornby passing contact switches. The green and red wires on each passing contact switch are then taken out to the particular points motors they control. Actually the design I used was from an Australian website. I saw the dollar prices and assumed they were US dollars, but now know different! I constructed the circuit from their schematic. You can get the bits from Maplin or Cricklewood Electronics. It's a very simple but effective circuit and is designed to work with a 15V DC or AC input. The larger the capacitors the more clout the unit has. I used a single 4700uf capacitor. My Select unit can now switch points and change a sempahore signal at the same time; I have two points motors wired in parallel to do this. There's no real limit to the number of points that can be switched in this way because you don't typically switch more than one set at the same time. The recycle time of my unit is less than a 1/4 second. Swiching points has no effect on a running train and is all powered via the 15V accessory socket.

I'm sure that the Australian company would rather you bought their kit than constructed your own from locally bought parts! However, there must also be ready made units available, all based on fairly similar circultry.

Happy modelling
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