"All Stop" Emergency Stop Not Working Correctly

[westernwill]

I have carried out some more testing using a 125 train. My findings are as follows.

If I run the train at its fastest speed and stop it normally it takes 45 inches to stop.

If I use the "Stop All" with controlled deceleration it takes the same length as would be expected.

Unticking the controlled deceleration box and then pressing the "Stop All" the train hesitates and then runs on for 30 inches before coming to a halt.

If I turn the Power to the Elink off the train runs on for just 15 inches before stopping.

We need HRMS to tell us what should happen before stating that there is a problem.

I would guess that a Stay-Alive decoder, because it still has power, can stop a train, as we used to say many years ago, on a sixpence.

It is not a major problem for me, but does anyone else have any thoughts on this.

[OssieB]

Update on my problem with "All Stop". After a lot of time spent by HRMS last weekend and me doing elimination trials, HRMS were 100% convinced that the problem was with my eLink unit. They suggested that I contact Customer Care and discuss sending it back for repair or replacement. This I duly did on Monday and it was received back today. What an excellent service - thank you Hornby Hobbies. They were not able to replicate the emergency stop problem that I am experiencing, but they did find another minor fault, so they have supplied me with a new unit FOC.

Unfortunately, the new eLink has not resolved the problem. I have reset loco decoders back to original settings, tried different power supply, change USB cables, had only 1 loco on track, disconnected all accessory decoders, tried on an isolated length of track, all to no avail. I have also tried using a different laptop running RM in evaluation mode, again without any success.

From information received from HRMS, RM sends a signal to all the loco decoders to shut down and stop, but does not cut off power to the track. Therefore, it appears that this signal is being mis-interperated by the Hornby H8249 decoders. How could all 9 of my Hornby decoders have become corrupt? Is there a CV that influences this emergency stop procedure (bearing in mind that I have reset CV8 to 8)?

Any advise would be appreciated. Other than Westernwill, has anyone else experienced the same problem with Hornby loco decoders or any other make?

BarryO

[Fishmanoz]

To my knowledge, there is no CV in 8249s that would affect an emergency stop.  The range of CVs that can be addressed in an 8249 is limited for a start, download the leaflet from DCC section of the site if you don't already have one of those supplied with them.

[96RAF]

A decoder listens for and reacts to several DCC signals:

1. bespoke signal to its own address (long or short as set up) - it takes note and actions the command e.g. speed variation, function on/off, etc.

2. broadcast signal to all decoders - e.g. emergency stop - it takes note and actions the command.

3. consist command - if part of the nominated consist (simple or advanced depending upon decoder capability) it takes note and actions the command e.g speed change, individual loco function on/off, etc.

4. monitoring all DCC commands - if not to its own address (individual or consist) it will ignore them.

Your R8249 decoder is basic and will hear nothing more than commands to its own address and boradcast commands.

What it does with a broadcast command is limited by what is set in its memory, e.g. decelleration rate.

Any loco should if the power is killed to the track stop within the engineering limits of its design, e.g. flywheel motor, worm and screw gearing, etc. Some will run on and some will stop dead.

[OssieB]

Thank you Fishmanoz and RAF96 for your interest and imput especially RAF's descriptive decoder functioning. From my exchange of emails with HRMS they did clarify that the power to the track is not cut off on the emergency stop with the RM/eLink setup, unlike the Select and RM/Elite setup where the power is cut. To quote "The dead stop facility (unlike controlled stops) sends a loco stop DCC signal, which is interpreted by the loco decoder to cease power to the motor immediately."

In my case, I do not have any locos with flywheels, so this does not answer why it is happening. Some are can motors, an X04 and the rest are Ringfield. As I have said previously it is only happening on my locos fitted with Hornby decoders. The one loco I have fitted with a DCC Concepts Zen decoder stops dead as it should do, whilst all the Hornby fitted ones hesitate and then carry on to a controlled normal stop.

BarryO