Model Railway Forum

Context I am returning to model railways after 40 years and am building a layout using Peco 75 track, electrofrog points, DCC Cobalt digital IP motors and NCE Procab control. All the equipment is new. I did a lot of reading and researching before starting and feel I am getting to grips with DCC and current methodologies. This forum has been most helpful and I learned a lot from it. Now my question:

So far I have layed the track on board (effectively a double track through station with crossovers and sidings). Cobalt digital IP motors are installed on the points,and wired up via a Bus and programmed in. Everything works, trains run properly everywhere, points all operate as they should and I have set up macros on the Procab to control routes. It all works.
However, I have an electrofrog double slip as part of the system. It works but every time I switch on the power to the layout one of its cobalt motors does a "cycle of switching left-right-left" then settles down to work. is this "normal" or is their something I should be looking at to sort it. None of the other 7 Cobalt motors do it by the way.

Hi - I have a code 75 double slip which is operated by two Cobalt iP's. I'm no expert, but the only thing I could suggest is to try programming that point motor again. Obviously this is not a serious problem, but just something you could do without. I expect one of the experts will come along and give you a proper answer. I can operate my iP's both through the Hornby Elite and toggle switches (on-off-on, sprung to centre) - in both cases power is supplied through the bus cables - I use the toggle switches all the time - to fiddly using the Elite. Sorry I could not be of more help. BB

There is some time a need to put a diode on the switch wires, i thinks is mention on the DCC concepts site....

The problem is with the Cobalt motors! DCC Concepts recommend a work around or fix using diodes. Here is their detail for the fix... Link to item
IMO its a cop out by DCC Concepts for poor design!!

Thanks for the replies. I am only using the first 3 terminals on my cobalts; the first 2 for the DCC bus and the third one for the frog. I have no remote switches (or wiring) so don't see where I could fit the diodes.
I will try re-setting then reprogramming the one ip motor concerned to see if that helps. If that fails I may replace it with another one to see if that sorts it. (though I can't say I relish the idea of spending more time under the layout board!)

jrsaito wrote: ↑Sat Nov 17, 2018 8:52 am Thanks for the replies. I am only using the first 3 terminals on my cobalts; the first 2 for the DCC bus and the third one for the frog. I have no remote switches (or wiring) so don't see where I could fit the diodes.
I will try re-setting then reprogramming the one ip motor concerned to see if that helps. If that fails I may replace it with another one to see if that sorts it. (though I can't say I relish the idea of spending more time under the layout board!)

Hi
If you are not using manual push button or switch operation then the diodes are not needed.
Readdressing may overcome the problem.
If it doesn't contact DCC Concepts in the UK and ask for the defective Cobalt to be looked at with a view of repair or exchange etc

I believe this is normal. I had trouble with my cobalt and talking to DCC ( when I could reach the over the phone in Perth ) swititching as you powered up was normal. Apparently depending on the installation so motors don't come to a complete rest when they switch. Every time you powder up it rectifes itself. I think this is what they told me.

Just for reference - DCC Concepts are now UK based - DCC Concepts Ltd, The Sidings, Settle, North Yorkshire. BD24 9RP. Tel: (0)1729 821 080 Email: sales@dccconcepts.com

Having given a rather non helpful answer at the beginning of this thread, and read the answers that came later, especially Brian's. Having seen his link, I remembered I had this problem some years ago and contacted DCC Concepts. This is the answer I received:

*** Hi - I suspect that the wires are either light or quite long? We had a client with this issue a while ago but its rare.

To reproduce it ourselves we tried lots of wiring combinations and yes, it is possible with long wires or some wiring where they are close to/pass close to other wires that there is an interference induced by the length/inductance and the proximity to other wires. This phenomenon will not usually affect Cobalt iP until it is significant though.

(Its the same sort of interference that can often affect detection and the general delivery of DCC signals, causing random events... which is why wire routing and general good practice is important as it is with ANY data networking)

If you experience this then add diodes as shown here to those motors - that will filter the interference and should fix your problem.
Richard***

The link that DCC Concepts attached was the one Brian gave.