Help with decoder programming

[petertg]

Hi there users of Zimo decoders, more specifically of MX630. I have four of these, three in old power-hungry locomotives (two are Lima electric and the other is a Wrenn steam) and one in a more modern model, perhaps more than required. The fact is that I have fitted it in a Bachmann Derby lightweight and I can't quite get the motor control right. My layout contains first radius curves, so I have to keep the speeds under control. Apparently, the original Derby lightweight had a top speed of 62 mph, which, I believe, corresponds to a CV5 setting of around 125. I checked this fairly closely with the Scale speed calculator available elsewhere on the web. But I can't hit on the most appropriate settings for CVs 2, 3, 4 and 6, since the unit shows very little acceleration until about speed step 20 and the speed drops to a crawl under step 18 when slowing down. Can anyone advise what settings I should have for CVs 2, 3, 4 and 6 and any others of interest to get a more or less uniform acceleration? I have the Zimo instruction manual, but can't work things out clearly. No sound is involved.
I have just read elsewhere on this Forum about the "coasting" facility, with indications given by "paulibanger".
Any help with understanding the Instruction Manual will be highly appreciated.

[shibushe]

HI. First you are at least using a decent decoder, I use a number of MX630s so you should not have any trouble.

CV6 is a CV that is important. Its also a CV that is invisible only you know its been applied and how much.

You have CV5 set to 125 you now need to decide the percentage of 125 to apply to CV6.

At 40% this would be 50.

I can understand you frustration it getting your Locos to perform we have all had that experience.

What you could try is a decoder reset sometimes this cures a number of problems.

Be aware of decoder default settings your instruction sheet will show these.

As for the settings CV 2, 3, 4, these are your choice every Loco will be different.

Can I suggest. Decoder reset to default 3. work out your preferred top speed with throttle open.

Then apply your preferred percentage to CV 6. Run the Loco at 3 see what happens.

If all is well, then you can play around with, 2,3,& 4.

[HLT 0109]

Have you got the right value in CV29?  Unless it is set to respond to the CVs 2, 5 & 6, it will respond to the speed table using CVs 67-94 and (I believe) ignore the value you set for CV 6.

 

edited to change "CV 5" to "CV 6" at the end.