Another DCC NuBee Question: Speed Matching

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IronBeltKen

Lazy Daydreamer
I've been trying to teach myself DCC for a few weeks now, but I still
haven't figured out speed matching. I can't get the speed on my Kato
SD38-2 to respond to anything - I even set CV5 as low as 10 and it
still races like a jackrabbit, compared with the Atlas CW40-8 that I'm
trying to MU it with.

I'm sure there are other CVs involved too, but I can't figure out what
they are, let alone what to set them at.

Is there any logical procedure to doing this, or is it mostly an "art", hit-or-miss, depending on what brand of locos are used?

Any feedback appreciated...
 

HaggisKennedy

Coal Shoveler
Here's some info:

http://www.trains.com/TRC/CS/forums/997827/PrintPost.aspx

Did you get a booklet on the decoders with your locos? Do they have any info on the decoders that are in there? What decoders are you using?

CV2 is start voltage. CV5 is Max Speed, CV6 is Mid Speed. Some old Atlas decoders don't support CV5 or 6, but I think yours should be the newer 4-function decoders which do. There should be info on the Atlas site on that decoder.

Start both locos using a CV2 setting which just gets them moving at speed step 01. It gets tedious from there on.

Kennedy
 

HaggisKennedy

Coal Shoveler
OK, I see you're on the Digitrax list; they've apparently given you some more info to work with (not to mention some info I've asked for earlier)....

:D

Kennedy
 

IronBeltKen

Lazy Daydreamer
Thanks Kennedy,

I got an answer late last nite on the Digitrax forum. Apparently I had overlooked CV6; once I started playing around with that [and CV5] I was able to make the Digitrax-equipped Kato move slower than the QSI-equipped Atlas (the Kato previously had been going 2x as fast as the Atlas). I never could get both locos moving at an identical rate, but I can always set my 'top' consist unit at a speed which may be a teensy-bit faster than the trailing unit.

I guess I'll figure all this stuff out someday...
 

HaggisKennedy

Coal Shoveler
Unless you want to spend a ton of time speed-matching, getting close is about the best you're going to get. You ought to also consider what the top speed on your layout is. If you're never going to get to SS28, then you ought to concentrate on the lower steps. The alternative, of course, is to set your max speed low.

This is what I did with a couple of Atlas BW40-8s and an Athearn GP60B. None of them wanted to play nice, but after concentrating on the lower speed steps, they work fine together, but only in one direction, mostly.

There's been much discussion as to where the faster loco should go in the lashup. Some say put that loco in front, but I go with those who say the fast loco should be in the rear. I go with this because the weight of the train will put drag on the loco, slowing it down. Once it slows to less than the lead loco, the lead loco now assumes part of the towing load, and brings the rear loco up to the same speed. You probably won't see much slack inbetween the locos. I prefer this to having the fast loco in front being dragged down by both the train and the slower loco.

Kennedy
 

Alcomotive

Grandson of ALCO Bldr
[/QUOTE]
There's been much discussion as to where the faster loco should go in the lashup. Some say put that loco in front, but I go with those who say the fast loco should be in the rear. I go with this because the weight of the train will put drag on the loco, slowing it down. Once it slows to less than the lead loco, the lead loco now assumes part of the towing load, and brings the rear loco up to the same speed. You probably won't see much slack inbetween the locos. I prefer this to having the fast loco in front being dragged down by both the train and the slower loco.

Kennedy[/QUOTE]


Interesting thoughts there or rather a theory tested and run....cool I have never given it that much thought and always placed the faster unit on the point....I like you explanation....:cool:

this may see improvements in OPTIMUM POWER in tractive control and effort.....me likes power!

but i must admit the majority of my locos are pretty well balanced on their speed tables but will re-visit this now with this new insight in hand...:D
 
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dougcnup

Member
train speedometer

Last January my model railroad club purchased train speed. here is a link to site you can buy it from.

http://greenwayproducts.com/buy_speedometer.shtml

I try to get my engine to creep alone at around 3 on my throttle I set my midrange so engine travels at 35mph at 50% throttle and 72mph at 99% throttle. I am able to match any 2 or three engines together with no problems. One member even uses helper engines on a steep grade with a s curve in it. Only takes a few minutes to set up too.almost all my engines run together the exception is a proto2000 SD45. damn speed demons, Cv values are very low.

I set CV2 (start voltage) at 10
CV5 (high voltage) at 255
CV6 (mid voltage) at 127
CV116 (Torgue compensation kick rate) at 3
CV117 (Torgue compensation kick strengh at 25
after i adjust cv's to these setting I start to run engine over the speedometer, and start to make adjustments to mid range(CV6) and max range(CV5)and leave CV2, 116, and 117 alone


CV 116 Torgue compensation kick rate is how frequently the motor is kicked at slow speed. Typical adjustment is 2 to 4. The smaller the number the more often the motor gets a brief voltage kick. Factory default is 0 (off). A value of 1 applies kicks continunuously. The max practical value is about 6.

CV 117 Torgue compensation kick strengh is how hard the motor is kicked at slow speed. Typical adjustment is 4 to 25. The larger the number the more voltage is applied in each kick. The strenght of these kicks fade out raio metrically as speed is increased providing a smooth transition to normal motor operation. Factory default is 0 (off), usable range 0-50.

I use NCE decoders in all my engines either DASR or D13SR

hope this help ya some, good luck
Doug

Hope this helps ya
 
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