DCC Automatic Station Stop

FurkaSOCal

FurkaSOCal

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Can anyone give me a suggestion on how to set up an automatic station stop with a DCC layout? I used to have this on my analog system and it was alot of fun. I run an NCE PH Pro 10 amp system. Currently all of my decoders are ESU Loksound XL v.4.
 
PhilP

PhilP

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5 Jun 2013
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I think you will find how (if) this is implemented is 'manufacturer-specific'?

As i don't 'do' either, NCE or ESU, I can't comment further.. :(
 
Greg Elmassian

Greg Elmassian

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Many decoders support the ABC (Automatic Braking Control) invented by Lenz.

Basically you make asymmetric DCC and then the loco will slow to a stop.

Many adjustable parameters.

Read this, you will see how the "asymmetric" DCC signal is done with a few diodes, making one of the "voltages" higher than the other...


Zimo does this too.


Greg
 
FurkaSOCal

FurkaSOCal

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26 Dec 2017
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San Diego
Many decoders support the ABC (Automatic Braking Control) invented by Lenz.

Basically you make asymmetric DCC and then the loco will slow to a stop.

Many adjustable parameters.

Read this, you will see how the "asymmetric" DCC signal is done with a few diodes, making one of the "voltages" higher than the other...


Zimo does this too.


Greg
I know this is an option that could be triggered with a magnet for ESU, the trouble is once the locomotive stops im not sure how I would have it start again after a time delay.
 
Greg Elmassian

Greg Elmassian

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There's even more features in decoders, so you might read through the manual and see what features there are in your particular decoder.

It also depends how you want to automate things.

In the diagram I linked, you can "bypass" the "asymmetry" circuit and I think it will resume, but I'm not an ESU expert.

I'm sure there are way more knowledgeable people here, hopefully they will chime in. I'm interested how people have addressed this too.

If I was to build an automated layout, I think I would use a central computer program, put the "smarts" there in terms of detection, and then decide if I can also incorporate unique features of decoders, or completely automate the detection and motion with the software.

If I just wanted a few things to automate, I'd probably research what my "favorite" decoders could do and perhaps integrate those features.

Greg
 
John S

John S

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5 Nov 2017
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Which version of ESU Decoder?, and does it have the ability to implement Lenz® ABC Brake Mode?

To implement Lenz® ABC Mode requires altering the Symmetrical DCC waveform (positive and negative waveform that are equal ) to Asymmetrical, meaning that the positive and negative parts of the waveform are no longer equal.

To achieve creating an Asymmetrical waveform, all that is required is a circuit consisting of four diodes in series, with another reverse biased diode connected in parallel. When current flows, a voltage drop occurs, which results in the positive half of the waveform being reduced by 2.8V.

For a simple basic test setup something like the 1N5001 general purpose rectifier diode would suffice, if testing proves to be satisfactory then try using UF5404 type diodes.

Asymmetrical DCC is used on isolated sections of track. The use of a switch* is optional**, to activate or deactivate Asymmetrical DCC in the section.

When the loco now enters a track section with the modified DCC waveform, the decoder senses the presence of the Asymmetrical waveform and brings the train to a stop. Refer to the relevant sections of the decoder manual for alteration of the respective CV's for correct operation, and for stopping and **restarting.

Unfortunately as the NCE System does not have the advanced features of a Massoth or PIKO system, where the implementation of STOPS & STARTS etc, are simple to implement as the software is already provided by the manufacturer in the Firmware, the NCE system may well require additional hardware and software trickery to achieve the same routines as provided by Massoth across the range of it's and PIKO's DCC equipment.

*Could also be achieved by using Function Decoder or a Switch Decoder output, to power a relay.

123385_10c7f01b81661cbe15a9064c88eb81f1.png





Further reading on NCE products, for use with computer control.

BD20 BLOCK DETECTOR:



AIU01 Auxiliary Input Unit:



Software program designed for use with NCE DCC equipment. A Track Model Railroad Electronics and Control.

 
Last edited:
Greg Elmassian

Greg Elmassian

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OK, the asymmetrical waveform generated by the diodes in the link I provided and replicated above is independent of any control system, Massoth, ESU, NCE, etc.

Slowing the train to a stop is done by the decoder.

So how do you start it again? Does the decoder timeout? In the example above, the asymmetry is never turned off. In the link I provided, you can turn it off with a decoder.

Inquiring minds want to know. :)

Greg