I don't really know what you guys call these things as I don't find myself being overly computer savvy. What's a thread vs a post? I wouldn't know. However I am actually replying to a previous.....person's questions...regarding throttle notches. I'm kind of gleaning from the Nov. 2015 posts that there may still be some confusion. Notch One is Notch One. Idle is Idle. Zero amps being loaded in Idle. Notch One will actually load amperage...100-200 amps say although it's virtually not enough to start most tonnage trains on level terrain. Notch One is just enough to stretch the slack out between the power and maybe the first few cars. Typical tonnage trains will get underway by Throttle 2 or Throttle 3. (N2 or N3)By tonnage trains I mean something of a ratio of .7 horsepower per ton (HPT) up to 1.0 or 1.1 or even greater.
Tons are tons whether you were a engineer on the SP or running trains for the PC. The aforementioned engineers may have had more HPT available to them to start their trains but had greater percentages of terrain to operate over of course. If they had 12,000 HP for a 8,000 ton train that'd be 1.5 HPT. On a LEVEL stretch they very well may get it started on N1 as 1.5 HPT is well above average needed to start that train. You have 3 of your favorite SD40-2,s on the point? 3,000Hp per? 9,000 for the consist? If your trailing tons is 9,000 then you are at 1.0 hpt. We climb Byron Hill southbound out of Fond du Lac WI. enroute to Chicago with a minimum of .8 HPT. The CN will let us go without a shover involved if we have a bit less HPT as long as we have AC's. In some locations your train is stopped on a grade (crew changes, sidings, laying back off crossings until he's ready for you to bring 'em on) and to restart it it might take N4 or more to get it moving. I once stopped a Potash train at the bottom of Byron Hill (1.09% at it's steepest) with 1.1 HPT about 8 years back and waited for the guy ahead of to clear Byron. Stopping where I stopped was my inexperience as a Engineer back then or maybe was it my sense of adventure? Either way at 1.1 HPT I now know it'll take N6 with DC's to get a 1.1 HPT train started from the whistle post of Lost Arrow Rd. Don't do that! I was on pins and needles as my throttle started to exceed more than I was expecting it should. I remarked to a senior engineer with a smile on my face later at some point that "I now know you can start 1.1 HPT from the whistle Post at Lost Arrow Rd." He wide eyed said "Are you kidding Brian? You've got to lay back and get a run off the knob a mile before the bottom!" I realized it after the fact. Surprisingly that train managed to do very well speed wise up hill once I got it going. 3 GE's or EMD's or a combination of definitely has enough tractive effort to separate a train. They will generate forces greater than the knuckles can withstand. Only 2 motors? Not so much. I got lucky that day pulling upwards of 1500+ amps from a dead stop with 3 motors in N6. So Idle is idle. N1 is a whole another animal. N8 is even better yet! By the way when starting a slacked train we don't normally just notch out and let it stretch. If it's heavy you'd likely feather that independent brake say between 20-40 pounds or whatever to keep it moving at 1 mph or less until it is all moving. No jack rabbit starts unless you're the 20 car local. Then who cares?
