LGB 21602 DCC compatibility with Revolution DCC



G Gauge, Raising Peaches, Apricots
1 Feb 2012
Southwest Oklahoma, USA
Something still fishy... you did state it was a Lenz, did you ever read the mfg number and version?

If you note my pages linked earlier, the 55020 by lenz cannot have CV29 changed.... and the fact it is working tells me you are in 28 speed step mode...

My guess is you have a Massoth 55020 or newer decoder... I know you can find a 55020 manual from LGB, but note it is for the newer Massoth 55020... but still I have a hard time believing you are in 14 speed step mode.. because the THROTTLE must put out different commands too, and I have never seen a system that can "sense" the mode the decoder is in.

In any case, it is working.

I'll bet that if you put the Revolution throttle in 128 speed step mode it will still work (and give you more precise motor control)

Read back from CV7 is 13, read back from CV8 is 99. I's possible that, the Lenz is fooled by the commands from the Revolution. As an experiment I counted the button pushes from 0 to WOT. Got 27 before the display on the handheld read 28 (100%). The engine was running like a scalded rabbit at anything past 13, so am not sure if the speed increased or not. As long as the end result is consistent operation I will play politician and let it work.

There may be errors in the diagram below.


Greg Elmassian

Greg Elmassian

8 Mar 2014
San Diego
Well, 99 is Lenz for sure, the speed at 100% could be toned down with CV 5...

Sure sounds like the throttle is in 28 speed step mode.

So what does not make sense what the decoder model is...cannot be a 55020 since it is 14 ss only...
Can't be a 55021, since that was only made by massoth.

In any case, it is a Lenz, and it is working. I tried to find a history of Lenz decoders, but not found.

The version of 3 means it is not all that old ( they just went to 4, so maybe it is not the original decoder from LGB)