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My first posting but I'm sure you guys can help me.

I'm starting a layout after many years absence and reading through this forum and the usual publications it seems obvious to go down the DCC route for a new layout However I have a number of old Poole built Farish loco's that I would like to convert to DCC but I'm not sure what effect DCC will have on these as they were built to either be running or left in an isolated section. They were not built to sit idle in a powered section of track, is it likely to burn out the motor and should I plan to add some isolated sections or do the decoders help protect the motor? Finally I only intend to use two function wired decoders on the loco's (can't see any reason for more functions as I don't plan to use sound), are there any types I should avoid installing on Farish kit.
I have just DCC'd Two Poole built duchess locos using the digi hat, one with a second hand Lenz 0.4amp decoder and one with a new Lais decoder costing £13 on ebay, both are extremely smooth, even on number one speed, I use a gaugemaster prodigy advance and the basic settings I have programmed are: Start voltage 40, acc 8 dec 8 TV180 these settings work well for me, but other smaller farish locos only need start voltage set at 1, for some reason 40 seems okay for the duchess engines, maybe as they are heavier than the plastic bodied jobs. If you use the digi hats, be aware that you can't remove them easily as the insulation sleeve tears easily- I tired the fit and did a insulation test before fitting the brus and spring, and destroyed the kynar sleeving, in the end tamiya masking tape did the job insted, but the second loco i fitted the brush and soring then tested for insulation and all was good. Hope this helps, but do it as they are well suited to this conversion. One loco was new old stock, the other was used but in good condition when I bought it.
 

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Just fitted a Lais decoder to one of the Poole built duchess locos and speed steps 1 to 4 were like gear changes, very jerky and a big increase in speed. It was suggested online to cancel BEMF so i did this and the loco woudn't move at all, so I did a factory reset, and then I tried the acceleration number, which I originally set at 9 for the lenz decoder, but I tried 30 as a trial, and the difference was amazing! much smoother take off from start, so in the end I put in 50 for acc, and 10 for dec, and it totally smoothed out the problem, so for Lais decoders this may help anyone having the same problem.
 

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I find it surprising how little use is apparently made of CV's 3 and 4. For 'road' traction that has to move heavy trains, 50 is about as low as I start. Values in excess of 150 in CV3 will deliver a good representation of a steam loco starting an unfitted freight at the heavy end of its load rating, picking up one wagon at a time at below walking pace so the guard isn't thrown off his feet, then gradually grafting up to the usual circa 20 mph line speed.

I am regularly disappointed at exhibitions when DCC operated locos snatch an unfitted freight all into motion within two seconds, and are running at circa 20mph within a train length.

Seeing such an operation at one show on a very well modelled layout, and the DCC system in use was Lenz which I have, I asked whether I could demonstrate what was possible. The loco was already programmed so it ran at scale for 20mph at speed step 12. I used PoM to set CV3 to 180, then resumed control and started it away by entering speed step 12. Predictably enough it smoothly and slowly eased into motion, and went away gradually grafting up to line speed. Opinion was violently divided. One of the exhibitors was most impressed. The other three wouldn't consider it: why would we want to do that?; we exhibit to drive the trains...
Well most online sites i have gone on recommend between 5 and 15 for acceleration, but I guess it depends on the make age and model of loco, but it shows that some experimenting with numbers sure does come up with some good results, anyway as long as you know the factory reset code you can always start over, but thanks for your input, as I thought I may have done something wrong, even though it has the best results, DCC is a long learning process for a beginner like me.
 
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