DCC Running diesels in multiple with sound

Dog Star

Western Thunderer
Thinking to the day when we get a second Class 37 running under DCC, I am prompted to ask about getting the engines to run in harmony. We are using Lokpilot / Loksound V4 chips at the moment and have no plans to change from that base.

An engine fitted with a Lokpilot V4 moves off as soon as the throttle is opened. An engine fitted with a Loksound V4 does not move off as the throttle is opened, rather there is a lag - the diesel engine sound speeds up and the engine moves after a few seconds. Independently these behaviours are not problematic. However, if an engine with Lokpilot is coupled to an engine with Loksound, with the two engines linked via "consist", what happens when the throttle is opened?

Does the engine with Lokpilot sit there with wheels spinning? Does the engine with Loksound get dragged around even though the sound suggests that unit has yet to move?

How is the lokpilot decoder "slugged" so that the units move as if in unison?

regards, Graham
 

Steph Dale

Western Thunderer
Graham,
It's just the case (or should be!) of programming the acceleration (CV3) and deceleration (CV4) of the LokSound into the LokPilot. After that it's worth checking the speed curve or min/mid/max CVs are the same in both.
You might find that you need to put a few tweaks in around the motor control (CV51 to CV56) to get the best running.
Steph
 

richard carr

Western Thunderer
Steph/Graham

I'm sure you need to do that Steph to get them running together but sound decoders do have a delay like the real thing. For example, in real life when the driver throttles back on class 47 the engine revs, lots of clag is emitted from the exhaust and about 5 seconds later it starts to move, the LS V4 decoder mimics all of that but the none sound one does not it just goes.

Richard
 

TheSnapper

Western Thunderer
Graham

IMHO, it ain't going to work.

You really need closely-matched locos, ideally with the same drive train & decoders configured with the same settings, in order to set-up a successful consist group.

For a bit of fun, you could always try driving each one with separate controllers!

Tim
 

Steph Dale

Western Thunderer
Graham,
Or wind the feedback out on the two decoders so they don't fight.
BTW, ESU imply that what you're trying to do is possible so it might be worth asking them and/or SWD. In my experience they take around a week to get back to you, but the advice trends to be worth having.
I'm betting that somewhere there's an undocumented feature in the LokPilot...
Steph
 

Steph Dale

Western Thunderer
Graham,
I had a look at both manuals yesterday evening and failed to find anything specific about synchronising two different decoders. I've seen plenty in ESU's literature about the two decoders having the same drive. I also know it's possible to run the Select with LokPilot as plenty of US-outline modellers manage it.
The feedback (BEMF coefficient) will be one of CV51-56, but without the manual in front of me at the mo I can't check.
Still worth asking ESU/SWD I reckon...
Steph
 

richard carr

Western Thunderer
Graham

You need to get a Lok programmer, it makes life so much easier then onthe motor controlsection you just tickthe box that says no back emf.

Richard
 

Dog Star

Western Thunderer
DCC-novice here.

What is the impact of reducing the "control reference voltage" (BEMF) on motor behaviour?

I can see the benefit of a graphic-based method for programming CVs... there appears to be a few options and at prices between (say) £50 and £125. Anyone care to suggest why a Lokprogrammer is a better purchase than, for example, a Sprog?

thanks, Graham
 

Steph Dale

Western Thunderer
Graham,
It affects speed, I think. It'll also have a knock-on affect on the other motor control CVs.
I have Sprog, LokProgrammer and the QSI programmer. I only use the two latter ones for playing with sound as I find the Sprog's roster management so damn useful. I wouldn't buy any of the bespoke programmers unless I was playing with sound files if I am perfectly honest.
Steph
 

richard carr

Western Thunderer
Graham

The biggest effect is on top speed, if you want it to go fast up the CV value, 14 volts works fine though and often less.

Richard
 

Dog Star

Western Thunderer
So two weeks after posing the question I have come to the conclusion that there is no simple answer and possibly no answer at all. As things stand - and working with the most recent online instruction manuals - there is no CV which has the functionality of slugging a Lokpilot to work with a Loksound (which incorporates a delay on starting). On the other hand, the Loksound manual v4.6 records that there is a CV which has the functionality of removing the start delay - with the warning that to enable the functionality shall result in a loss of synchronisation between the loco movement and the sound of the engine.

A moment of contemplation re-inforces my conclusion given at the beginning of this post for there are several sound projects for Class 37 diesels and those projects reflect different engine variants / refurbishments. To match a Lokpilot to the behaviour of a specific sound decoder, by the alteration of one or two CVs would appear, to me, to be beyond the expected functionality of a generic decoder.
 

richard carr

Western Thunderer
Graham

I have had two days my 37s running together without any problems, one has two maxon motors the other only one. Both have loksound v4 decoders fitted.

I don't think you will ever get good running from a lok pilot and a loksound decoders running together.

Richard
 

Dog Star

Western Thunderer
I don't think you will ever get good running from a lok pilot and a loksound decoders running together.
In spite of what I have been given to understand by someone whose expertise I respect I have to agree with you.

So looks likely that we shall follow your lead and fit twin Maxon motors and one Loksound V4 to each of our class 37s.

regards, Graham
 

Cliff Williams

Western Thunderer
For my customers I always advise a consistent standard, same decoder, same ABC gearbox with Maxxon motors.
Its the easiest way if they are being run together and you use Lokprogrammer to transfer the settings for CVs, speed curve, back emf etc.
 

Terry Mercer

New Member
Hi all. I have just found that the V4 Lokpilots can be programmed with "virtual Sound" which will give them a starting delay to match Loksound v4s.

Using your Lokprogrammer, go to the "Driving characteristics" menu, You will see "starting delay" (just after Power Pack and Preserve Direction.) Tick the box marked "Delay starting if virtual sound drive is enabled" Then you can programme in the time to wait before start to match your Loksound V4.0

This should match the Lokpilot to the starting delay of the Loksound v4.0

Cheers

Terry
 

Steph Dale

Western Thunderer
Thanks for posting that Terry - I'm relieved that I wasn't imagining it (or translating it incorrectly). I wonder where the functionality is buried; I can see I'll have to have a play with my LokProgrammer...
Cheers,
Steph
 

Terry Mercer

New Member
Hi Steph,

I have downloaded a screen shot from the web about how to find this function. I will attempt to post it on Western Thunder. (I am totally new to WT, so not too sure yet how things work)

Cheers

TerryLokpilot.jpg
 

Steph Dale

Western Thunderer
Terry,

That's great - if it's on that screen it looks to be on a CV rather than a firmware or profile change.
I'll have to 'dig' and see what I find for those who don't have a LokProgrammer.

Cheers,

Steph
 

Terry Mercer

New Member
In my attempt to post my first picture on WT, I forgot to give credit from where I got the info. It came from RMweb.Co.UK, the forum on "Enabling Virtual Sound on a Lokpilot V4.0 (Non Sound), a thread started by Bricktrix. Have a look. It makes for interesting reading.

regards

Terry
 
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