I have an N scale Kato SD45 and an Atlas SD35 (along with an Atlas SD26) that have the same ESU LokSound Select Micro (different sound files though). I set the deceleration (CV4) to 255, and the Kato will act prototypical and take a long time to stop. However, the Atlas engines, with the same CV4=255, will stop very short. They will stop in the same distance with the same speed setting when the Kato has CV4=20. What's going on? They all have the standard linear speed settings.
The two may have different firmware revisions. 255 momentum should take FOREVER to stop - and I recall that ESU doesn't use a 0-255 range for the momentum CVs - 32 may be the top limit, which is STILL a very very long time. I think the one time I tried setting a decoder for maximum deceleration momentum, it completely circled my previous 10x13 layout two times. That's a bit of overkill.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
That won't make one take a long time and the other stop instantly as if no momentum were set.
Exactly. These decoders were all purchased within the past month. Firmware is the same. On the Kato, CV 4 = 255. I set the same thing for the Atlas, and it's not coasting like it should. I want to MU these units, but can't due to the discrepancy.
The only way you can be sure they are the same firmware is with Lokprogrammer. However, I would simply adjust them, particularly the one that acts as if it has no momentum, and use a number lower than 255.
I was close - page 20 of the Loksound Select manual says the permitted values for CV3 and CV4 are 0-63. I think you got lucky the one works at all on 255.
If the NMRA spec is followed, a value of 255, when used with 128 speed step mode, is over 1.7 seconds per speed step, so shutting off the power fom full throttle would take almost 4 minutes to stop. At 28 step, it would take OVER 4 minutes. Are you really getting that much momentum out of the one?
Randy,
I don't go full throttle on my locomotives. At speed step 5, it takes about 45-50 seconds to stop. I have two Kato units that have the same sound decoder (SD40-2 and SD45) and same sound file. I have 255 programmed into CV4. The two Atlas units have 255 programmed into CV4 and they do not have the deceleration that the Kato units do. Not even close.
If I put 63 into CV4 of the Kato units, they stop pretty quickly (about 5 inches from speed step 5-6). About as much time as the Atlas units do with CV4=63.
Someone else mentioned that it might be because the Kato has a motor that goes fast while the Atlas has a ScaleSpeed motor. If that's the true cause of the reason, I might have to adjust the Kato units to match the Atlas versions. Ugh.
See, this is what's pissing me off. On page 40 of the manual, it says that the range for the deceleration rate is 0-255. But on page 20, it says the range is 0-63 (like version 2 of MRC decoders). Whomever wrote the ESU LokSound Select manual should be fired. I'll believe it's the 0-255 range.
That seems like an extremely long time from speed step 5. Not that there is any proof ESU exactly follows the NMRA recommendations (not a requirement), but the formula is (.896 x CV value) / # speed steps which is the number of seconds per speed step. Doing the math with 255 in the CV and starting at step 5, it should take about 9 seconds to stop.
Are you sure you don't have other modifiers set, like speed table or even a 3 step speed curve? Or additional momentum enabled on the throttle?
CV3 or 4 set to 63 should result in about 2 seconds to come to a stop from step 5 (again assuming ESU follows the NMRA formula, and you have th eloco set for 128 speed steps)
OK, at the end of the manual it says they calculate by multiplying by .25 to get the time to stop from top speed. So at 255, that's 63.75 seconds - from full throttle. Divide by 128 is about half a second per speed step, times step 5 (assuming the loco runs on step 1) is 2.5 seconds. If they actually base it on 28 speed steps, the same math works out to 11 seconds from step 5.
SO neither one really jives with the results you are getting. There's somethign else effecting that one loco. The motor should have nothign to do with it, the decoder is simply turning down the speed bit by bit, you cna replicate the same thing by turning the throttle knob slower. The only slight difference that the motor could affect would eb the point when it finally comes to a stop, a better motor or one where the decoder is better tuned for BEMF will keep moving at a slower speed step than one that is not, so you could gain a couple of seconds one wy or the other if one loco quits moving at step 2 and the other one keeps going even on step 1. But no way can that account for the vast difference.
The difference in the manual makes me suspect they changed this is the firmware at some point. Selects had a lot of changes in a rather short time when thy first came out - the Loksound group on Yahoo was full of suggestions for improving the operation of the decoder and fairly frequently Matt Herman would annouce that they made some changes and post an updated firmware.
I'm on 28 speed steps. I just timed it on my SD45. From speed step 6, it takes 32 seconds to stop. Yes, that's a long time, but I like it like that because it's realistic.
Any rate, the Atlas has the same CVs set as the Kato unit, with the exception of the horn. Yet the deceleration is less than a quarter of the Kato unit.
Hmm, that just doesn't jive with either the fomula ESU gives, or the NMRA recommended formula. ESU says that should be about 13 seconds, NMRA says almost 55 seconds. Using 28 steps. The Atlas one sounds like it might be following what ESU says.
Does either have a speed table enabled? Since you are using 28 - you have NCE? Does the momentum button actually program CV3 and 4, or does it add momentum at the cab level? Is shunting mode enabled on either decoder (I think Selects have that) - it cuts top speed by half and also cuts momentum in half.
Might be time to reset them decoders and try again.
Shunting mode is not enabled, and speed tables are not enabled.
What do you have in CV2? If one engine's CV2 is set higher than the other, it will make one stop faster than the other.
I guess I'd suggest setting CVs 2 through 6 to zero, and see how the engines run compared to each other. Then set CV 3 and 4 for each to a low number, like 20 or 30, and see if they seem to react the same. Then increase from there if necessary.
Maybe one engine is set for 28 speed steps, but the other for 14 or 128? I'd double check both.
Sorry if I missed it, but did you try setting CV4 on each to a lower number, like 60 and see how they responded? As a couple of folks have mentioned, it sounds like the manufacturer may have changed the maximum value allowed for CV3 and 4. Even if the two were bought close together, one might be different in that respect from the other.
I'd point out that if it takes nearly a minute to coast to a stop from speed step 5, you have the momentum set unrealistically high, but that's another discussion....
So I figured out what the problem is. Apparently, and I'm not sure why, but even though I had the bit in CV29 set to digital only (DCC), CV50 is ANOTHER analog or digital configuration variable. On the Atlas engines it was set for 2, which is set for enabling DC. Once I set that to 0, which disables it, the deceleration was matched with the Kato units. What a load!
Edit: Well, it seems the deceleration changes based on if the sound is on or not. If the sound is on, then the deceleration is very low, i.e. it stops rather short. If the sound is off, then it takes a long time to stop (upwards of 30 seconds from speed step 7 out of 28).
WHAT IS GOING ON?
Interesting. More links to the common design between the v4.0 and Select - in v4.0 there are two options in CV50 - DC analog mode and AC analog mode (yes, some v4.0 decoders can operate on an AC layout that use momentary pulses for reversing - think Marklin 3 rail stuff). In Select the only option is for DC analog on or off because Select doesn't support AC analog or the other non-DCC protocols.
Interesting that there is no real mention of any of this having an effect on CV4. The only mention given is that if using Brake on DC, CV4 is ignored and the loco comes to an immediate stop. But that requires a section of track with DC and no DCC signal on it to act as a brake section, it has nothing to do with response to the throttle.
No kidding. Esu LokSound Select products are great, but their documentation stinks. Hopefully this helps someone else.
I'd suggest hitting up the Loksound goup on Yahoo, Matt Herman of ESU USA is a regualr there so besides others usign the decoders, the issue will get to 'official' ears as well.
I still say taking 30 seconds to go from step 7 to stop is actually not correct. Granted I am slightly biased because I never use 28 steps when 128 give so much finer control, but still that's 1/4 throttle, not full speed or even half speed, so it would be like going from around step 30 to stop in 128 step mode (there's not really 128 steps in 128 mode, some are reserved).
Randy, I put the throttle at SS 7 out of 28, used my watch, very rapidly turned down the throttle from 7 to 0, and it took 42 seconds to stop completely. I have CV4 set to 255. I like it this way because it's realistic. That's with the sound off. With the sound on it takes, 10 seconds to stop from speed step 7.
The 10 seconds is somewhat close to what the Select manual says in the table that lists all CVs and values.
The 42 seconds, just odd. Way more than what the manual says, and way less than what the NMRA definition says. CV4 at 255 on most any decoder is completely uncontrollable unless there is also an independent brake function you can engage.
By sound on and off, you mean with F8 engaged or not? Have you tried a reset on any of these decoders? F8 should not be the key to engage the switching mode (confirmed the Select does have this) which not only changes the speed but also reduces the effect of momentum settings, but maybe for some silly reason it is.
Yes, with F8 engaged and not engaged. If F8 (sound) is engaged (sound on), the deceleration time is DRASTICALLY cut. With F8 off (sound off) the deceleration time is normal (for me) and matches the Kato unit.
This is the most screwy thing I've seen, other than the deceleration values being impacted by the DC mode.
Only the Atlas one does this? The Kato one has the same deceleration regardless of the sound settings?
Only difference would eb the sound sets loaded - so it's possible there is something goofy in the Atlas one. Or the decoder firmware version.
Make sure CV253 and CV254 are set to 0. That's braking stuff that's supposed to only matter for brake on DC and Asymmetrical DCC, but you never know.
I still say, try a reset.
This is what's going on:
https://www.youtube.com/watch?v=CbMCb_lekzY
This is what the Yahoo Groups said to fix the problem:
Program CV31 to a value of 16Program CV32 to a value of 3(This sets up the index registers to access the correct page of high CVs i.e.>256)Program CV291 to a value of 0Program CV293 to a value of 64