Different DCC Systems--Same Loco--Different running operations

[villager6381]

 I always assumed that a DCC loco programmed on one system would perform pretty well the same on any DCC system.

  I recently took an Atlas Classic C424 sound equipped loco, which I had programmed on my Digitrax Zephyr DCS 50 to run on our club's Digitrax Super Chief system.

The loco performs acceleration & deceleration gradually as expected on the Zephyr, but at the club it jack-rabbit starts & stops. It seems as if it goes from zero to full throttle in an instant.

Anyone have a solution?

Thanks.

[rrinker]

Did you actually program CV3 and CV4 for momentum at all? The Zephyr has a momentum feature on the throttle that works with any loco, so you can crank the throttle wide open and it gradually starts up. Using that same action on a Super CHief or Super Empire Builder will result int he loco takign off like a scared squirrel. If you programmed momentum values in CV3 and 4 (CV3 for acceleration, CV4 for deceleration), it shoudl behave nearly identically on either system. Track voltage is probably a bit higher ont he Chief but not enough to make the difference between slow and smooth and jackrabbit.

                                  --Randy

 

[villager6381]

 Yes, the loco still performs as it did before on the home layout.

  But I'll have to check to see if the club layout is only 14 step speed next week. 

  Club track was clean & mine was the only loco affected.

 

[villager6381]

 Randy

    CV 3 & 4  are zero.   CV2 (start volts) is at 2

  Don

[CSX Robert]

Are you using the Forward/Break/Reverse lever on the Zephyr to start and stop the loco? If so, read section 15.2 "Brake Operation"(page14-15) in the Zephyr manual. The Brake lever on the Zephyr has an adjustable momentum level built in.

[tstage]

villager6381

Randy

CV 3 & 4  are zero.   CV2 (start volts) is at 2

Don

Don,

If CV3 & CV 4 is set to "0" then your momentum is only coming from your Zephyr, as Randy mentioned earlier.  You'll need to set CVs 3 & 4 to a value greater than 0 in order for your momentum to work on another system.

A general rule of thumb is to have deceleration (CV4) 1/2 the value of acceleration (CV3).  However, it's just a rule of thumb.  You can adjust your momentum however you want.

Tom

[wjstix]

What number you put into CV 3 and 4 will depend a bit on what type of decoder you're using. On some if you put in say 15 you're going to get a lot of momentum, but on other decoders it will only be a little bit. Depends on what the range is, some decoders only go up to like 30 or so while others go up to 255 or whatever.

When programming a new decoder installation I usually put CV 3 and 4 to about 12 to start and see what happens, and adjust from there. I'm running basically a switching layout so I like forward and reverse momentum to be about the same. With a center-off direction switch like my Zephyr and UT-4, I can get the engine running to about 7-8 scale MPH, and then just use the direction switch to switch cars without touching the throttle. With the momentum, the engine glides to a stop and smoothly starts without needing to adjust the throttle setting.