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SPoint Control on Hornby Select DCC Controller R8213

I am setting up my first dcc track installation.

Should points be controlled using a bus circuit powered by the "track outlet" on my Select Controller? Or is the purpose of the "Aux Output".


13828 posts

Community Moderator

If you want to control points by DCC then you need the solenoid point motors powered by an accessory decoder such as R8247 which is itself powered by the DCC track output.


If you want to control the points manually via switches and a CDU then you could use the Aux output to power the CDU but it will drain available power away from your track, hence only suitable for a few points, so most folk in this scenario with many points tend to use a completely separate power supply to their CDU and thence via momentary switching to the solenoid motors.

Halton Brat - Running Win 10, 64-bit - RM (Pro-Pack) with Elite as Controller-A, Select as Walkabout and E-Link as Controller-B - Locos are mostly TTS. http://www.halton96th.org.uk/robs_rails.html


12055 posts

Community Moderator

EDIT: Once again, Rob just beat me to it.


If you are going to use the 'TRACK' output of the Select to operate points. Then you need to connect 'DCC Accessory Decoders' to the track output of the Select first. The Accessory Decoders then in turn connect to the point operating motors.


As to which Accessory Decoders you use, that will depend upon what type of point operating motors you want to use. The Hornby R8247 Accessory Decoder will only operate 'Solenoid' based point operating motors. Each R8247 has four ports [one port per point]. Thus the schematic below can operate eight points directly. Multiple R8247s can be connected in parallel. Only two shown below to keep the schematic simple and tidy.


Note also, that with a Select. The Accessory Decoder ports must start at DCC Address 61 and not exceed 99. The factory default for a R8247 starts at DCC Address 01, therefore any R8247 Accessory Decoders you purchase to install will have to have their default factory addresses changed.


R8247 number 1 changed to '61 to 64'

R8247 number 2 changed to '65 to 68'

number 3 to '69 to 72' etc


Using Hornby R8247 Accessory Decoders with a Select



The AUX Output, of the Select is not DCC, the AUX output can only be used to operate solenoid point motors using analogue technology and a CDU [Capacitor Discharge Unit] must be used with the Select, as the Select AUX output is not powerful enough to operate points directly without one.


Using the Select AUX output via a CDU to operate Solenoid points manually via Analogue control.



The little red / silver switches are Non-Locking Momentary Action Change-Over switches with a Centre-Off position. Any form of locking switch will not work. The following link is an example of a suitable switch to use.


Switch Link


CDUs are available form any good railway model retailer and via eBay, just search eBay for CDU.


TIP: As a newbie poster on the forum, just be aware that the 'Blue Button with the White Arrow' is not a 'Reply to this post' button. If you want to reply to any of the posts, scroll down and write your reply in the reply text box at the bottom of the page and click the Green 'Reply' button.


Particularly as my reply includes an image, using the 'Blue Button' may result in your reply being held back for image approval, even though it is an existing image.


See also – further TIPs on how to get the best user experience from this forum.



Chris........ Making the wood in the trees visible.

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