Have been using the Clinchfield F7 and had a few questions that the tutorial doesn’t cover: 1. The Rotair valve has options for freight, freight lap, passenger and passenger lap. In the tutorial it mentioned setting it to freight. Is that what I use all the time? What’s the difference between freight and freight lap? 2. There’s a unit selector switch that lets you go from 1-4. Tutorial says that you set it to the number of power units you have. Is that just locomotives with cab or does it also include the F-unit Bs without the cab? I’m assuming you include both. 3. There are 2 horn pulls one for “front horn” and one for “rear horn”. They seem to sound the same so what’s the difference and when do you use one or the other? 4. Does anyone have a breakdown of the transition lever and how to use it? The tutorial said to put it in shunt when you are yard switching and series parallel when you’re running but didn’t really explain what it does. There’s also a braking setting on it which I don’t know how to use. Thanks!
1) "Freight" and "Passenger" are for the driving cab, and mean that that brake stand has control of the system. "The "Lap" settings are for non-driving cabs. 2) IRL, that selector increases the voltage in the signal used to control dynamic braking throughout the MU- the signal was attenuated the farther it had to go, so the switch in effect increases the gain depending on the number of connected locos (As, Bs and if present SD40s as well). In game however it doesn't actually do anything, save add to immersion. 3) A blunder: there is only one horn, at the front, and the second pull shouldn't be there. Besides, it obstructs your view of the speedometer! 4) Old-school DC trains used, as a rough analogue to a "transmission," different configurations for connecting the traction motors; this kept the generator within its efficient operating range while varying the draw of each individual motor as speed increased or decreased. A transition can be seen thus as an analogue for shifting gears in a car. The F7 has automatic transitions, as did all EMD engines from the 7 series through the 45 series (Engines from the SD50 onward handle it differently). However, just as with an automatic-transmission car, you have the option to put it in "low," i.e. prevent it from upshifting when what you want is maximum torque. The steps on an F7 are series-parallel (pairs of motors in parallel are connected with each other in series, the slowest/highest torque setting), series-parallel shunt (a resistance load is placed in parallel to the series connections, reducing the back EMF and permitting higher power than pure S-P); parallel, with all motors in parallel with another, freeing armature current from field current and eliminating the "self-braking' feedback of series operation; and parallel shunt, again adding a load resistence across the system to further reduce EMF buildup - top speed). You don't actually have to worry about any of this- it's like an automatic transmission, just drive it. You'll notice the "upshifts" and "downshifts." So long as the lever is in one of the power positions it doesn't matter which one. The F-7 could be switched to manual mode (a switch inside the rear breaker panel, in-game put on the panel door)- but I don't know if manual transitioning is modeled in the game. The SD40 was automatic-only: the only purpose for its transition lever was to control older manual-trans units it might be lashed up to. The one essential function of the transition lever - in both locos - is to change over from power to braking modes. This is what turns on your dynamic brakes- an absolute essential on the CRR! Just remember, when changing over, to let your amps drop all the way to 0 first- you're reversing polarity on a 1000-amp generator, you DO NOT want to try to force it backwards! (IRL this could lock up the train, or in extreme cases blow the genset permanently)
