So, I decided to put the information out here for anyone else that might be interested. I bought my first LionChief Plus steamer today and wanted to compare it to the NW2 Diesels I already have as I had heard that the steamers did not behave as well at low speeds. I can report now that these comments appear to be rubbish...Almost.
For those that may not know, LC+ engines have 16 speed steps in each direction. while the knob has 41 stops, only 31 of these are unique. the middle 3 stops, dead center and one click either way all leave the engine in neutral. I expect this was done so that the train wouldn't move if someone was not spot-on in turning to the middle. The next 15 in each direction are the speeds, and the last 4 clicks have no further effect on speed.
For this experiment I measured out a length of straight track 66" long on one side of a long oval of fasttrack. This is 1/20th of a mile, Scale. I timed how long it took for each engine to travel the 66" distance at each speed stop on the throttle knob. Each engine was tested alone, pulling no load. Worth noting that at the higher speeds there is more error in the timing as it became too fast for eye-hand-stopwatch coordination. I'll probably build a timing track into my next layout using some fancy(not really) electronics for accurate measurements ar high speeds, but it doesn't seem worth the effort just now. Anyway, I used these times to compute the scale MPH speed for each speed step on each engine. I repeated the test twice on each engine, once with the track voltage set as close to 18VAC as I could get it, (18.08VAC true rms), and again at 8VAC, (8.04VAC true rms). At any voltage below 8VAC the engines will not operate correctly. I don't think it likely to cause damage but I don't recommend powering a LC+ engine off less than 8VAC.
As it turns out, what I found was that the Hudson did in fact have one less speed step at low speed than the NW2. On the hudson the first two stops are the same speed. This I find a little disappointing as it would make sense of it was the other way around. The hudson has a higher top speed and it would make sense if it had one more speed step. There is very little practical difference in either engine here, the diesel just an extra speed between 2 and 5 MPH. The difference only showed up when all the data was recorded, as the speeds present are more than enough for smooth slow speed operation... any reported appearance of 'poor' slow speed control is technically correct, but not really significant enough to matter in operation.
The other thing I found was that the speed steps all remained, more or less, intact at any voltage with within the 8-18VAC range. Only the highest step was not available at 8V on both engines with all of the other speeds (mostly) staying the same in MPH. What this means is that a LC+ engine will travel at the same speed regardless of track voltage, within the operating voltages of the engine, except that the highest speed becomes unavailable on lower voltages. I did not test to see what voltage this cutoff is, But I will tomorrow and add that information here with an edit. (that info here).
I am over all, very impressed with this, as it turns out the speed sensing part of these engines is very good. I will also have to test this, but I expect that the speeds will also remain the same when a load is being pulled. I found that each speed step is 133% of the previous speed on the Hudson with it's 14 speeds. The NW2 had each step about 125% of the previous speed with it's 15 different steps. With these speeds remaining consistent throughout the voltage range you can see just how steady the speed control really is. I expect that the fact that Lionel chose to use only 16 steps is the only limiting factor keeping LC+ from having comparable speed control to Legacy. There were some oddball speeds in both engines at low voltage where one speed was significantly different from the same setting at 18V, but only 1 such setting on each engine.
So, How good is LC+ speed control, anyway? Well, it is insanely consistent, without regard for variation in supply voltage. The actual speed is a trackable precise fractional value of the previous speed. Pretty solid design here, so good job Big L. Both engines I tested started at just under 2 SMPH. The Hudson had a top speed just over 90 SMPH where as the NW2 topped out at 80 SMPH. My conclusion is that LC+ speed control is every bit as good as any of the larger command control systems. It has only been held back by a desire to keep it from competing with the high end systems combined with the needs of a super simple remote with a center-off position.
For your consideration, here is the data I collected:
| Speed Step | 4-6-4 Hudson 18VAC | 4-6-4 Hudson 8VAC | NW2 18VAC | NW2 8VAC |
| 1 | 1.9 | 1.9 | 1.9 | 2.0 |
| 2 | 1.9 | 1.9 | 2.4 | 2.5 |
| 3 | 2.6 | 2.6 | 3.1 | 3.2 |
| 4 | 3.6 | 3.6 | 3.9 | 3.9 |
| 5 | 4.9 | 5.0 | 5.3 | 5.1 |
| 6 | 7.1 | 7.1 | 6.7 | 6.8 |
| 7 | 9.9 | 9.9 | 9.2 | 9.3 |
| 8 | 13.2 | 13.3 | 12.9 | 12.8 |
| 9 | 17.3 | 17.5 | 18.2 | 24.8 |
| 10 | 26.5 | 26.6 | 30.9 | 30.7 |
| 11 | 30.2 | 30.0 | 36.7 | 36.4 |
| 12 | 42.1 | 35.9 | 43.9 | 43.9 |
| 13 | 51.7 | 52.8 | 57.5 | 56.1 |
| 14 | 69.8 | 60.0 | 69.0 | 71.1 |
| 15 | 90.0 | 62.5 | 80.7 | 72.0 |
| 16 | 91.8 | 60.8 | 78.9 | 72.0 |
| 17 | 90.9 | 59.4 | 81.4 | 73.5 |
| 18 | 92.3 | 61.9 | 80.7 | 72.6 |
| 19 | 89.6 | 62.5 | 80.0 | 71.1 |
I left the data on the chart for clicks past where speed changes occur on the dial just so folks can see that these last few clicks have no effect on speed. Variations are mostly caused by my bad reaction times in recording the data.
JGL
Given the fact they use a tach sensor to determine speed, it's logical to think you'd get those results, it's nice to know it actually does the job that well.
