Adjusting Speed steps, so same on ALl locos

S

Simon Potter

Srpott40
hi

I run a massoth the system and have a range of different locos which have a variety of chips installed. My railway does not have any of these fancy train detection systems or automatic points etc. As my railway is quite large I often enjoy setting two trains running then enjoy watch them run! However one always seems to catch the other up. (Even if set to same level on controller)

Do anyone have a way of changing the loco cv so that they run the same speed? I have a large range of locos so trail and error on the speed steps is not my preferred option!!
 
Trial and error is the only way Simon. As with analogue models - different models have different gearing and in built resistance.
Two identical models will often run at slightly different speeds.
If you want to play, you need to amend the speed curve for all the different speed steps - quite a job on one loco, let alone a collection.
Its also a bit fiddly, you would need to switch off the default speed curve in CV29, bit 4 to off. This disables CV2, 5 and 6 (start voltage, top speed and mid speed). Then you create your own speed curve using CVs 67 to 94. Thats a lot of CVs to be playing about with but a little easier if you have a programming tool such as the Sprog or Massoths own.
Even then, the values given to CVs 67 to 94 would need to be different for each loco and trial and error is the only practicle way of finding out what value you need.
I just play around with one of the loco speeds until I get it near enough not to catch up the other, or vise versa.
 
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Set up a length of track with start and end markers. Choose your slowest loco and time how long it takes to cover the distance at different speeds - say slowest, quarter, half, 3-quarters, and full speed. That loco becomes your reference.

Then as Stockers says, you'll need to adjust the speed curve of each of your other locos by trial and error until to get as close as you can to the reference times.
 
Thanks, does anybody have any computer software where if i did get two
ntpntpntp said:
Set up a length of track with start and end markers. Choose your slowest loco and time how long it takes to cover the distance at different speeds - say slowest, quarter, half, 3-quarters, and full speed. That loco becomes your reference.

Then as Stockers says, you'll need to adjust the speed curve of each of your other locos by trial and error until to get as close as you can to the reference times.
Click to expand...

I was thinking that would be the best way of doing it, but that would take hours!!! (per loco)
 
I use a sprogg for programing and jmri. Works really well and you don't have to look up cv values for the speed curves and programing lights etc. Really easy to use.
 
The SPROG hardware + JMRI DecoderPro software is a great CV programmer (I have one), but whilst it will make entering the speed curve CV values much easier, it's not going to make actual speed matching any easier - you still need to do some relative timings and trial-and-error adjustments to get different locos with different mechanisms/gearing and different decoders running at the same speed for a given speed step. No way round that I'm afraid.

It shouldn't take "hours" per loco, maybe 15 minutes each once you've got the baseline times you're aiming for.
 
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Hello Simon,

You can achieve what you are looking for, but in a slightly different way, using some software.

I know this is supported by RR&Co and probably others too (sorry I haven’t looked at the other software options for a while so can’t advise in detail on those).

This method is slightly different to what you have suggested in that it doesn’t try and set up all decoders to go at the same speed at each step by adjusting CVs. It works by the computer software understanding the characteristics of each engine/decoder so that it can set the speed step appropriate for each engine to make them go at the same speed.

In the same way that Nick has suggested you set up a reasonably long length of track with detection points at each end. You very roughly program your decoders to have just slightly more than the max top speed you want, speed curves etc don’t matter but the loco has to move at all speed steps, you only need to check the CVs for the max and min speed (2&5) . The software automatically runs your engine backwards and forwards between the two end points at all intermediate speed steps (the software calls this profiling). The software works out and records the speed associated with each speed step.

When you come to run the engine you set the speed you want it to go at and the software selects the appropriate speed step to make it go at that speed. Similarly if you set another engine to work at the same speed the software will select the appropriate speed step for that engine. The speed step set on both engines don’t necessarily have to be the same, but the speed will be. This also allows double heading with decoders of different characteristics.

Now this may be much more complicated that you wanted, but it will achieve what you asked for. An issue is that you have to run your engines through the software (for example on a laptop or smart phone) and not with the throttles of the digital system to get the equal speed feature.

Another way to do what you want would be to set up a bit of automation with a few blocks so that trains running at different speeds can’t run into each other anyway. That probably wouldn’t require any more hardware/software than the method I have describe for equalising speed and would be much more fulproof.

Sorry if I haven’t explained that very well. I’ll be happy to answer any questions you may have.
 
When I first started, I thought like many do, to match some locos together, but this still does not solve the problem of being completely free to run any locos together.

I got a digital speedometer, run in 128 SS mode, and calibrate each loco to the speed step, i.e. SS 10 is 10 smph.

This allows me to set up any loco to a standard, and then not only do they all consist well to each other, but when I look at the throttle, I'm reading the actual scale speed.

Actually easier than matching 2 locos to each other and more benefits.

Greg
 
Greg Elmassian said:
When I first started, I thought like many do, to match some locos together, but this still does not solve the problem of being completely free to run any locos together.

I got a digital speedometer, run in 128 SS mode, and calibrate each loco to the speed step, i.e. SS 10 is 10 smph.

This allows me to set up any loco to a standard, and then not only do they all consist well to each other, but when I look at the throttle, I'm reading the actual scale speed.

Actually easier than matching 2 locos to each other and more benefits.

Greg
Click to expand...

Logical, clever, and 'blindingly obvious'.. Once told about it, of course!
:clap::clap:
 
I never run two locomotives at the sane time so for me a Max Speed for each loco that matches that of the prototype works for me (CV5,6). I play with the relavent 2 CV's then test the speed by running against an iPhone/Pad App called scale speed. Works for me and relatively simple plus quick for wach loco.
JonD
 
Whilst I have yet to try it most, if not all, DCC systems appear to have a "Consisting" option. Could this be used to achieve the desired result? If so what are the pros and cons of this method?
 
Consisting is simply assigning multiple locos to a single consist address for multiple-heading etc.
Modern decoders have a "consist address" which you can tell the decoder to respond to in place of its usual stand-alone address. Some DCC systems (eg. NCE) also support consisting by assigning the loco addresses to a single consist address within the system itself, which then sends out speed and direction commands to all the locos in the consist at the same time. I think I've seen this referred to as "brute force consisting".

Speed matching is kind of a requirement for consisting, it's probably the main reason folk go to the effort of speed matching throughout the speed range. You don't want locos in a consist bucking or dragging.
 
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ntpntpntp said:
. ............ You don't want locos in a consist bucking or dragging.
Click to expand...

You may want to turn off the BEMF (constant speed) function in both/all locos in a consist to stop this as well. CV49, bit 1.(on Massoth)
 
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I do limit the top speed of all locos to the prototype top speed, so for example a loco that goes 100 mph in the prototype, has a speed curve that is 1 speed step = the equivalent smph, until in this case speed step 100, I program speed steps 101 to 128 (effectively) to 100 smph too.

Greg
 
I just add or remove a wagon or two until the speed matches! I can run for up to 25 mins around my 40m track before I need to adjust the speed again.
 
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