DCC Short Circuit [R7277 Corner Layout]

[Chrissaf]

The problem has been covered on the forum before.

That layout has reverse loops not documented by Hornby, which require some isolation of track sections and use of a reverse loop module to make it work on DCC.

Someone will be along and post a back-link to the previous discussion telling of the rework details, etc

[Chrissaf]

This previous thread [clickable link near bottom of this reply] explains all. I direct you to read my last reply on Page 1 near the bottom of the page of the linked thread which gives the solution.

 

As RAF says, the R7277 layout is full of 'Reverse Loops'. A R.L will instantly generate a 'short circuit' on a DCC layout where all track is all live i.e DCC point clips fitted.

 

I define a 'Reverse Loop' as a track layout scenario where any route taken through the layout by a loco, ends up with the loco arriving back at its original starting point, but facing in the opposite direction. This would include a route via a Turntable.

 

Fixing this issue is going to be expensive. You need four 'RLM's [Reverse Loop Modules] plus ideally a Select 1 amp power supply upgrade to 4 amps. See the solution on the clickable link below.

 

A cheap alternative solution is to remove the track pieces marked in black pen on the R7277 layout plan on the linked solution page and replacing them where needed with straight bits of track to re-instate the main loops. The track pieces marked in black pen are the pieces that are common to all the 'short circuit' generating paths through the layout plan. Removing the black pen marked track pieces removes the 'short circuit' paths. The downside is that removing those track pieces takes some of the playability factor away from the layout plan.

 

Your choice. Cheap solution that limits the functionality of the layout plan OR an expensive solution that keeps the full functionality of the layout design.

 

Hornby R7277 Large Corner Layout DCC Reverse Loop solution.

https://www.hornby.com/uk-en/forum/post/view/topic_id/30963/?p=1

 

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.

 

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

https://www.hornby.com/uk-en/forum/tips-on-using-the-forum/

 

[Chrissaf]

Hi all, having an issue with a DCC system, having purchased the large corner layout [ R7277] complete with a Select controller, i have no problems running 4 trains on the main lines and in both sets of sidings, however as soon as i change one of the points on the main lines to swap engines across, the system shorts out, i have fitted all the point clips and even without an engine on it shorts out instantly i move one of the offending points [ there are just 4 that this happens on]. Any advice on what i am doing wrong - Thank you