@christopher N&W posted:One thing that would concern me about DCS is slipping on the grades. To me it seems like the stripes would move very fast if slipping occurred on the grade and the reader would interpret that as the engine is moving faster? Then wouldn't the engine adjust for that increased speed of the slipping wheels and slow the engine down? That interpretation and response would not be a desirable one as far as I can see.
Very perceptive of you. I have had this happen in only one case: The MTH P5a's (either Box cab or modified) have a wierd drivetrain.
The locomotives have all three axles powered on a long rigid wheel base: One vertical can motor powers one axle, the other vertical can motor powers the other two. At the top of an uphill superelevated curve, invariably one set of drivers slips. And the loco gets confused in the manner you described. The locomotive does not stall, but does go through a hiccup. It does not matter which set of drivers is forward, or which motor has the tach timing tape. It's not all that noticeable (In fact, you have actually seen it Chris!). It has even been known to happen in three rail MTH P5a's with traction tires (mine have been converted to 2 rail).
The design is basically dumb: The result of poor weight distribution, an unsprung rigid frame, wide axle spacing, and, I am guessing, the marketing based insistence on using two motors. Even though they power three axles. The fixes are not easy: sprung drivers, regearing for one motor, and/or a cogged belt connecting the flywheels. All are complicated solutions. The easy solution is what I do: just consist two (or three) of them together. Another is to raise the railhead at the offending spot, but that's a bit ugly
I have never had this happen with any other loco I own. If it did, I would add a second loco
