CAB1L Speed Steps

From the CAB-1L Manual (page 9, 73-7155-250), under the removable panel:

Note that on LEGACY/TMCC2 locomotives, L, M and H settings change the number of individual
speed steps your locomotive supports. A setting of L gives 32 speed steps, M yields100 speed steps and
H provides 100 speed steps with added momentum.

MR mentioned that the TMCC engines would only operate at 32 speed steps while Legacy engines operated at either 100 or 200 speed steps. I wonder if the CAB1L could address the TPC 300/400 which offer several different speed steps.

Good question, I couldn't find anything that had an answer as to whether or not the TPC300/400 step settings (80/200/400) can be used.  I don't have a TPC 300/400, only an old PowerMaster.  Jon Z would be the one to provide an answer.

I'm using DCS, with my Base1-L hooked in so I can control my TMCC/Legacy engines.  The DCS handheld gives me a choice of 32 or 128 speed steps.  My Legacy GP9, 3rd Rail E7, and Railking RS3 with ERR Cruise Commander all move slowly at the 128 setting.

I can't imagine how 400 speed steps performs, the engine must really C-R-A-W-L at that speed

Legacy Locos can operate at 32, 100, or 200 speed steps.  Non-Legacy only 32 speed steps.  Cab1 and Cab1-L operate in relative mode, speed step selection is in the loco with running Legacy locos, not the Cab. 

With the Cab1 or Cab1-L, use the L(32), M(100), or H(100 w/ some momentum) on Legacy locos to set desired operation.  Non-Legacy, this sets the momentum; with the exception of aftermarket locos which cannot support Momentum if they have Cruise.

The TPC will operate just fine on all speed step selections with the Cab1 or Cab1-L, as he TPC was designed back in the TMCC only days.  With a Cab-2, use the Cab1 setting.

This is a great topic for me. I have a Legacy GP9 and just purchased the Cab 1L/Base 1L set but haven't set it up yet. Steady performance at very low speed is a big deal for me and my PS2's and 3's in DCS mode are inconsistent. Even in conventional, the Legacy is better than any of these. Hopefully this will carry over to command control.

I'm going to pick up a Cab1L set in a couple of weeks. One of my engines a converted Williams scale GG1 uses an ERR Cruise M board, it was too difficult to use the Odyssey boards, and it is programmed in the Legacy system as an R100 engine.

Will the R100 programming remain if I remove my Legacy 990 system and install the CAB1L system instead?

Scott,  This should not be the case.  What do you mean inconsistent?  MTH engine under DCS should track along at what ever speed setting regardless of track layout and loading on engine.  G

Gman,

Yes and no. Like you said, all of my engines by themselves on a straight will obey the speed input and hold it. Add a bunch of weighted cars and 180 degrees of 036 curves and things change. Not much but they do. At 5 smph for example I have only one diesel (a PS2) that will hold rock solid steady speed everywhere on the layout. The others all need to get to 7 smph and up before they "smooth out". At lower speeds they all have trouble holding perfectly steady speed. To the casual observer it would go unnoticed but not to me. Am I overly picky about it? Absolutely, but that's how I "roll".

This is not that uncommon.  Note that MTH only specifies that 5MPH and higher "scale" speeds are supported.  The slower speeds frequently work, but many DCS locomotives won't smooth out until 4-5 MPH. 

If you put enough of a load on any cruise equipped locomotive, it may run out of the reserve headroom and not be able to track consistently at the set speed.

Lots of load and O36 curves will certainly run up the difficulty of maintaining a constant speeds for any cruise control.

Last night I backed my PS3 switcher up to a heavy consist that included the all metal auxiliary fuel tank for the Veranda turbine. Throttled up to 5 smph and she wouldn't budge. Wheels were spinning but no movement. Yeah, so maybe I overloaded just a little.

Once wheelslip enters the picture, all speed control bets are off!  I have noticed my Lionel Legacy PRR T1 Duplex will sometimes lose traction on the truck with the speed sensor, then it just sits and spins.  The other truck doesn't get any power as the spinning wheels indicate to the speed control circuitry that I'm going the commanded direction.  That can happen on any dual-motored locomotive, only one is speed controlled, the other motor just receives the same voltage in parallel.