Dash 9's re-rated?

[crazytiger]

The caption for this shot, http://www.railpictures.net/viewphoto.p ... 211&nseq=0, says that NS re-rated 36 of its Dash 9's. Is this true?

[mp15ac]

All that is required to change the rating is reprogramming the computer. This is possible with any modern locomotive.

Stuart

[Big Bri]

Here's a list from 9/19/2010 of the 4,400Hp Dash-9W's:

9275, 9276, 9299, 9305, 9306, 9312, 9318, 9333, 9356, 9378, 9382, 9392, 9395, 9403, 9421, 9422, 9429, 9431, 9442, 9448, 9452, 9460, 9467, 9469, 9496, 9499, 9505, 9514, 9518, 9520, 9525, 9546, 9566, 9584, 9597, 9599, 9601, 9605, 9608, 9612, 9614, 9623, 9628, 9637, 9640, 9644, 9651, 9653, 9661, 9676, 9680, 9689, 9693, 9698, 9701, 9702, 9725, 9726, 9739, 9745, 9765, 9769, 9796, 9812, 9816, 9817, 9825, 9829, 9832, 9833, 9836, 9838, 9841, 9847, 9883, 9889, 9907, 9918, 9923, 9953, 9967, 9971

Bri

[essdee50]

Reprogramming the computer? I know in the electrical cabinet there is a key switch and with the turn of a key the HP rises from 4000-4400hp.. Is there more involved than this? I run the darn things all the time and am asked this by many people. Just know what I see but would like to know more about it..

[jgallaway81]

The definition that was listed in Trains a few years ago regarding this issue indicated that the change was a software modification to the fuel-rack system.

Now, having programmed in QuickBasic in the early 90's, I can see how this MIGHT work...

Code: Select all

$switch = var(hpswitchposition)
if $switch = "4000" then goto #4000fuelcode
else goto #4400fuelcode

Obviously, this isn't the exact coding used in the system, but it does show how easy it would be to make the software be changed by the position of a key lock.

As for the validity of the whole issue... I've taken units up the east slope in Altoona and watched the system show a consistent 41**hp in full throttle with a heavy train. The last couple of weeks, I have noticed a couple units that were pushing close to 4500 when maxed out.

[SooLineRob]

FYI:

Canadian Pacific's GE C44AC units have a toggle switch on the control stand (or IFD screen on a GEvo) that allows the Engineer to select either 4000HP or 4400HP.

Normal operations call for the switch to be left in 4400HP position. The loco will produce 4400HP in Notch 8 from 0.1MPH to 25MPH while accelerating, then automatically reduce to 4000HP at speeds above 25MPH. If the loco speed drops to 15MPH, then the loco will again produce 4400HP. This is deemed a fuel saving feature.

The only time these locos should be run in the 4000HP setting is when there's a problem with the unit, or an older DC traction trailing unit won't produce any load due to an "electrical glitch".

[emdpower75]

The NS C40-9W locomotives that I have been in have all been equipped with a toggle switch on the back wall to go between 4000 and 4400 horsepower. The switch has some sort of wire wrapped around it to prevent the train crew from adjusting it at their free will and is designated mechanical department only. I have heard(but not witnessed) that there is a way to bypass something in the electrical panels to enable the unit to go to 4400 hp without messing with the switch.

[Roscoe P. Coaltrain]

FYI:
Normal operations call for the switch to be left in 4400HP position. The loco will produce 4400HP in Notch 8 from 0.1MPH to 25MPH while accelerating, then automatically reduce to 4000HP at speeds above 25MPH. If the loco speed drops to 15MPH, then the loco will again produce 4400HP. This is deemed a fuel saving feature.

This would appear to be a better system than what NS has been doing. Let the computer control it, provide the extra HP when necessary and remove it when unnecessary, and remove the human element of any manual key function.

It could be these NS motors are getting the software upgrade that allows the key to stay in 4400 while still getting a 4000 rating by computer.

Anybody been on the newest 8025-series Gevos to say for sure whether the key control thingy is still there on these brand new units?

[MBTA1052]

Are the ES40DCs equipped with this same technology as well or does it only effect the Wide cab Dash9s??

[Engineer Spike]

I had a NS locomotive consist recently. Apparently one of the units was rerated for 4400hp. I have heard that there is some kind of switch on them to change between 400 or 4400hp. While inspecting the units, I always check blue cards since sometimes they try to slip an expired unit in, hoping it will make it back before it turns into a pumpkin. Most of the -9 units say 4000hp on the blue cards. This one particular unit said 4400hp.