DCC programming problems

[PWS]

I’ve returned to modelling for my grandson, so it’s been a long time since I’ve done model railways.  What a fantastic step forward in quality in the intervening years!  I went for DCC as it seemed logical and more flexible.  But I need help folks!!

Problem No 1. It’s difficult to re-address locos.  The controller system doesn’t work even when carefully following Hornby instructions.  The seven red LED blinks never happen immediately after pressing the select button.  Sometimes I get 4 blinks a faint ‘click’ from the loco but no change of address. Returning after a half hour sometimes works.  I have tried with two different Hornby controllers – same result.  Also same result with two different traction units.  One is a Hornby 0-4-2 tank with decoder fitted by Hattons and the other is a Lima DMU with decoder fitted by a local retailer (the DMU never causes any trouble in operation but I haven't been able to reprogramme the address).   Eventually re-addressing of the tank happens successfully and I’m not sure how!  Any ideas on a solution?

Problem No 2.  After a derailment crazy things often happen.  The loco after re-railing runs without being addressed and with no speed set on the controller and with any address number selected.  I have read about this happening on other forums.  And sometimes the DMU parked in a siding (it has address No 3) leaps into action at full speed.

All advice from you exerts (and there must be many of you with tons of experience) would be very welcome.

[Chrissaf]

Welcome to the forum PWS.

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I have tried with two different Hornby controllers – same result.

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Different controllers have different issues and different solutions. It would help us, if you told us what two controllers you have tried?

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For example, two Hornby Selects. One Select and one Elite. Maybe even non Hornby controllers. The more information you provide, the easier it is for us to help.

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With regard to Problem 1 - are you saying that at the present time, all your locos except the 0-4-2 tank engine have the default 003 DCC address because you haven't been able to re-address them yet?

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How many locos do you have in total and what DCC addresses would you like them to have?

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The controller system doesn’t work even when carefully following Hornby instructions.

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With great respect, but the number of times posters have said 'I have followed the Hornby instructions' and after more indepth questioning it transpires that the instructions due to poor Hornby documentation have been misunderstood or important steps have been overlooked is very common.

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Therefore, could you specifiy WHAT instructions you have been following i.e The ZZZ User Guide Manual, pages XX to YY.

[KNAP]

I appear to be having a similar  problem in that recently Railmaster/elink is not recognising ID 3 or any new IDs. I cannot run a new loco with ID3 or a new ID address, although I can change to an existing loco ID address.

[Rog RJ]

The first thing to try in both of these cases is to reset the controller, assuming they are Hornby Selects.

[2e0dtoeric]

All new loco's (and 'loose' decoders) come addressed as 03.

When your controller starts up, it defaults to code 03.

So - the wise thing to do, after an initial test of a new loco or decoder, is to rename it to any other number EXCEPT 03 or 01!

Picture all your loco's as telephones, and your controller is the exchange - if they all have the same number, when you dial it, all the phones will ring!

If you are using a Select, it only has a limited range of numbers, up to 59, if I recall, and only two digits. There are lots of threads in here about this.

You are also advised to disable dc running. Again, lots of threads about it, so there is no point in repeating it all.

You have to connect the 'program' connectors on the back of the controller, to a separate track, to programme a decoder. It is advisable, although not essential, that you disconnect the running track wires from the sockets while you do this - just in case! You CAN switch the running track wires to the program connectors, but then everything on the track will be reprogrammed as well, unless you remove them all!

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The 'runaways, after a derail, tell us that you have NOT disabled dc running, and the culprit decoder thinks it has received a dc instruction to go - at 16v - so it takes off like an F1 car at the green light! (Dirty track can also cause this!)

 

[poliss]

Although the Select manual has a setting for disabling DC running, it is not clear whether it applies to the decoder or only the Select itself.

[2e0dtoeric]

OOPS! Nobody noticed! - rename it to any other number EXCEPT 03 or 01!

I meant 03 or 00, of course! 00 is dc (sort of) mode, that fries your motor if you park a dc loco anywhere on a DCC track.

[Fishmanoz]

Leaving aside KNAP's problem, it is very different despite his thinking it similar, I suggest for loco programming the Select be disconnected from the layout and connected to a short length of track only.  Ensure this track is spotlessly clean and that the wheels of the loco to be programmed are similarly clean and the pickups well tensioned onto the backs of the wheels.  This also avoids having to remove everything from the layout when programming, you only remove the thing to be programmed, not everything else.

 

Now try to reprogram its ID and see how you go.  If still a problem, press gently down on the loco as you program it to see how you go, that will usually fix it.

 

Concerning your "DC runaways" after having a derailment and short on the layout, I suggest you press stop on the Select and disconnect from the power supply.  Clear your short and power up again and all will be ok.

 

The permanent way to stop runaways is to disable DC running in the decoders by adjusting their CV29 value but the Select can't do this due to its limited capability.  It won't directly address any CV, only do what is available through its menus (ID, accel, decel etc).  Only Elite or eLink can do that.

 

[Icurus]

Hi PWS and welcome back to the railways and DCC :)

 

Are you programming the Loco's on a seperate bit of track?

 

What controller are you using?

 

And the runaway's, thats what trains that move off on their own are known as, are due to the Decoder chip's DC compatible CV being active, this can be de-activated thus stopping that from happening! :)