Weird

[Fixair]

I have laid the Peco Code 75 track and it has been wired in accordance with Peco instructions for DCC operation. I have been testing the running of locos on it using a Bachmann controller and 12 volt D.C.just to make sure that all is well before connecting up a Power Cab operation. The weird thing is that occasionally a loco will stall very briefly at various places on the layout and reverse its direction. My layout is a tail chaser around the perimeter of a converted garage with pointwork allowing trains to move into and across three circuits of track.

 

Can anyone shed light on this before I go any further?

 

Regards 

 

Ron

[smokebox]

Does the loco that you are testing with have a decoder fitted?

[Enterprisingwestern]

I would check and confirm your frog polarities initially.

 

Mike.

[34theletterbetweenB&D]

If you plan to operate using DCC, why not test with DCC right from the get go?

 

To explain, DC is very tolerant of faults like brief short circuits and poor contact, and DCC isn't! You don't want to trouble shoot for DC and then have to repeat the process for DCC; and especially if the build has been made in some way permanent - such as by ballasting - on the basis that it worked satisfactorily on DC, thus making shortcomings with DCC difficult to correct.

[Geep7]

My first thought is that perhaps at those points where the loco stalls and reverses, you've accidently reversed the dropper feed wires going to the bus wires (assuming you have bus wires of course).

 

I've done it myself before in a tailchaser type layout with DCC, as I forgot the orientation of the bus on each side of the layout.

 

How have you wired up the frogs for your points? Are they using any polarity switching, or just using them out of the box (assuming you are using Peco).

[PaulRhB]

Just to be clear this is running a chipped loco on DC?

 

It could be the decoder dc setting, does it happen with all locos?, I've had it happen on dirty track with certain loco and decoder combinations only on dc, put on the dcc and the problem goes away.

Change to a different make decoder and the issue goes away! Heljan locos can play up with Zimo, Gaugemaster or lokpilot, (strangely not loksound!), and Bachmann didn't like the Gaugemaster one either.

Edited November 8, 2017 by PaulRhB

[Fixair]

Does the loco that you are testing with have a decoder fitted?

Yes it has a DCC chip fitted.

[Fixair]

I would check and confirm your frog polarities initially.

 

Mike.

I have wired them all according to the Peco turnout instructions downloaded from their website.

[Fixair]

If you plan to operate using DCC, why not test with DCC right from the get go?

 

To explain, DC is very tolerant of faults like brief short circuits and poor contact, and DCC isn't! You don't want to trouble shoot for DC and then have to repeat the process for DCC; and especially if the build has been made in some way permanent - such as by ballasting - on the basis that it worked satisfactorily on DC, thus making shortcomings with DCC difficult to correct.

OK I will connect the power cab and proceed from there.

[Fixair]

My first thought is that perhaps at those points where the loco stalls and reverses, you've accidently reversed the dropper feed wires going to the bus wires (assuming you have bus wires of course).

 

I've done it myself before in a tailchaser type layout with DCC, as I forgot the orientation of the bus on each side of the layout.

 

How have you wired up the frogs for your points? Are they using any polarity switching, or just using them out of the box (assuming you are using Peco).

I am using the Peco switches that fit under he point motors and following the wiring instructions for that arrangement.

[smokebox]

Yes it has a DCC chip fitted.

That explains why the loco reverses. The reason may be a brief short circuit or change of polarity or even a brief interruption to the power which can all cause decoders to behave strangely. Some decoders are more prone to strange behaviour than others.

[eastglosmog]

I had a similar problem with my Dukedog - see this thread http://www.rmweb.co.uk/community/index.php?/topic/125359-odd-behaviour-of-a-dukedog/?hl=%2Bbachmann+%2Bdukedog with no DCC chip fitted.  See response #4  by 34RD, which gives the answer which was OK for me running DC but not for you if wanting to use DCC!

[RexAshton]

I recently did a DCC conversion for a client which while it worked fine prior to despatch exhibited the same problems you describe on his layout. Initially we thought it might be a decoder fault but as an experiment the decoder was removed and refitted, factory reset and then re-programmed. Result? Problem solved an d the loco has performed as expected ever since.