Very basic DCC question

[TEAMYAKIMA]

Apologies for a VERY basic question.

 

Am I correct that if I bring a selected loco to a stop in my fiddle yard (and then go off and run various others) that loco will automatically be selected for the same direction if I return to it?

 

What I mean is that many diesels are difficult to guess if they are facing forward or in reverse. If I drive loco A into the FY 'in reverse' will it default to 'reverse' when I return to it?

 

I hope that makes sense.

 

Thanks

 

PAul

[66C]

Hi Paul

 

It would help if you told us which DCC control system you are using.

 

Some systems, such as the Digitrax Zephyr, have a physical direction switch and that would determine the direction of travel.

 

Regards.

[TEAMYAKIMA]

Hi Paul

 

It would help if you told us which DCC control system you are using.

 

Some systems, such as the Digitrax Zephyr, have a physical direction switch and that would determine the direction of travel.

 

Regards.

 

Apologies - Digitrax

[JST]

I don't know but it's one of the reasons I fitted cab lights to my diesels.    

Edited March 29, 2018 by JST

[TEAMYAKIMA]

I don't know but it's one of the reasons I fitted cab lights to my diesels.    

 

 

Good idea! My diesels have directional lighting, but hidden inside a 20ft long 18 road fiddle yard they will be difficult to see especially if at the head of a train going away from the operator.

 

Paul

[Grovenor]

I realised, reading this, that I was not sure of the answer, so just had a play.

The loco retains its headlight when deselected so clearly the decoder does know which way it was going before it stopped. But it has no way to communicate that info to the controller (assuming you don't have transponding or similar). So what happens depends on the controller, mine just defaults to forward when selecting a loco. If your controller keeps a roster and stores the last used direction then things might be different, but that would depend on using the same controller as for the last move.

Regards

[pauliebanger]

ZIMO decoders have an interesting feature. As well as the usual forward and reverse, there is the ability to set 'East' or 'West'. Don't get too hung up about these names, it could equally have been called 'In' or 'Out' (of bay platform or covered fiddle yard), or 'Clockwise' or 'Anti-clockwise' on a roundy roundy layout.

 

The purpose is that the decoder knows which 'end' of the loco has been driven into the dead end, and when you select the equivalent of 'out', the decoder automatically sets the correct direction of travel.

 

That is, the operator will not need to know in which orientation any loco was 'parked'; the decoder will decide if it should move in the direction of the locomotives' forward or reverse in order to leave in the necessary direction for exit.

 

The slight fly in the ointment is that this only works in conjunction with an expensive ZIMO MX10 controller and ZIMO hand-sets which have the necessary additional direction key.

 

Best regards,

 

Paul

Edited March 29, 2018 by pauliebanger

[WIMorrison]

If you are using Railcom and an automation program that can read and use Railcom then you will be able to see the direction that they train last moved in.

 

Essentially a DCC decoder will remain in whatever state you use it until you issue a command to the contrary, which means if you park it up going forwards then when you next want to move it will go forward unless you tell it to change direction. This is the same when it is moving - if set at SS 18 going forward it will remain travelling forward at SS18 until you either change the direction or speed.

[Crosland]

It will always go the same direction, relative to itself, when you select forward on the handset. It will always go the other direction when you select reverse. What constitutes forward and reverse for the loco can be changed with CV29.

 

So, in your example, if you drive a loco in "reverse" into the fiddle yard and then come back to it later and drive it in reverse it will keep going the same way.

 

This is the difference between DC and DCC. With DC direction is controlled by the track polarity. Pick a loco up and turn it through 180 degrees and it will still go the same direction along the track. In DCC direction is relative to the loco. Pick a loco up and turn it through 180 degrees and it will go the other way down the track.

[Sir TophamHatt]

Some answers here have over complicated a simple question - although good for discussion.

 

The answer is (as @WIMorrison has said):

 

It'll stay in whatever direction you left it in.

[TEAMYAKIMA]

Some answers here have over complicated a simple question - although good for discussion.

 

The answer is (as @WIMorrison has said):

 

It'll stay in whatever direction you left it in.

 

Thank you - just the answer I wanted to hear. I can now plan my operating manual for my exhibition team - many of whom don't model at all let alone know about DCC!

 

Thanks all.

[Grovenor]

The decoder may well stay in reverse when parked, but only until it gets a command to change direction, which your controller may well issue as soon as you select the loco.

To avoid that the controller, or command station has to remember the last set direction and use that when selecting. Some systems may have this capability but not all do.

I suggest you test your system before completing those instructions.

Regards

[bgman]

Further to the above, if the locos etc are in a hidden fiddle yard maybe you could consider the use of a small cheap webcam hooked up to a laptop or iPad etc ?

 

Just a thought ?

[TEAMYAKIMA]

The decoder may well stay in reverse when parked, but only until it gets a command to change direction, which your controller may well issue as soon as you select the loco.

To avoid that the controller, or command station has to remember the last set direction and use that when selecting. Some systems may have this capability but not all do.

I suggest you test your system before completing those instructions.

Regards

 

 

I have been in contact with a Digitrax 'expert' and he tells me that my system will behave like I want it to - remembering which way the loco was going when it entered the FY. TBH I can put it to the test when I set the layout up in a local church hall to test run it. I'll know for sure by 12.00 on April 9th!

[melmerby]

Some answers here have over complicated a simple question - although good for discussion.

 

The answer is (as @WIMorrison has said):

 

It'll stay in whatever direction you left it in.

It'll go whatever direction you tell it on the handset, nothing more, nothing less. Forwards is forwards, reverse is reverse.

 

Keith

[Chiefy]

Apologies for a VERY basic question.

 

Am I correct that if I bring a selected loco to a stop in my fiddle yard (and then go off and run various others) that loco will automatically be selected for the same direction if I return to it?

 

What I mean is that many diesels are difficult to guess if they are facing forward or in reverse. If I drive loco A into the FY 'in reverse' will it default to 'reverse' when I return to it?

 

I hope that makes sense.

 

Thanks

 

PAul

Hi Paul, YES it stays the same is the answer. Also if you have any sounds playing these will continue. Also if while the Loco is stopped you went along picked it up, and turned it around then it would go in the opposite direction, as in the same Cab End would be the front of the loco (um does that make sense?)....        Say you had a diesel sat on the track ans stuck a bit of a POSTIT sticky note to the Front end..... Then we turn the loco round.... The postit note is in the other direction, but that is the direction the loco would move if you selected it and increased the throttle. Hope that helps....

[Nigelcliffe]

..............

 

What I mean is that many diesels are difficult to guess if they are facing forward or in reverse.

 

 

What it really means is that many people are not taught the clues to tell the "front" from the "rear" of a diesel loco.  Whereas we're all taught from a young age that the chimney is at the front of a steam loco, then get stuck when we're shown ones which are not arranged that way.

 

Most diesels with cabs at both ends are actually quite distinctive *If* you know where to look. 

Most have grills on the side and top for air intake towards one end of the body, but not the other end - that's a key clue to tell "front" from "back".    So, simple visual pictures with arrows for operators to tell what to look for could help. 

[Gilbert]

Fan for Front normally does me in most cases - and headcode lights help as well