via E-Mail
A few years ago, a radio personality (or deejay, if you prefer that term) in Shreveport, Louisiana was wrapping up his show I was listening to, and in is closing, he used a phrase which to me was not only catchy, but also had a lot of truth to it. He said "Knowledge is the key to a better understanding."
Of the many questions I have received during years of doing this monthly visit with you, a wonderful quality which comes through is the interested persons come out from all crafts of employees. When their situations are constructively related, everyone gets to share in the ultimate rewards. The first question is one which deals with the Distributed Power control system. The individuals who spoke with me about this were a yardmaster and some personnel from the diesel shop. Later on, I'll focus on other questions which were asked by engineers from both the Fort Worth North and Fort Worth South seniority districts. May the following responses provide satisfactory answers to us all.
The C44AC unit is equipped with the familiar LOCOTROL III stand alone control box console format, while the SD90/43AC has the Integrated Distributed Power system, where the displays and controls are performed via the ICE screens. The question here was: Can these types of control systems be linked together successfully? Yes they can.
To go more in depth: the developmental issue with this was not an inter-operability problem, but rather doing some fine tuning on some inconsistencies which deal with how well the IDP and LOCOTROL III systems could and would work together from both the mechanical and electrical standpoints.
The two systems have differences in the areas of operator interface, equipment setup procedures and consist limitations (IDP will control up to six remote consists, LOCOTROL III is only up to four), but yet, they are alike in their ability to provide control of the air brake, power throttle, and dynamic braking systems functions.
Achieving these current levels didn't occur overnight; nor was it confined to just these two particular systems (The UP's DPU locomotive fleet has a total of four different system formats).
There were testor trains operated at various system locations, along with developmental testing performed at the AAR-TTC in Pueblo, Colorado which dealt with eventually making successful the ability of mixing and matching any of these formats onto service for the same train. This saga doesn't end here though, as new developments for future enhancements are still taking place between all parties involved.
Why: It is to accomodate the program in use on the LOCOTROL III system, which has the emergency position recovery requirement for this step. Failing to do this will result in your getting a failure message after attempting to perform a brake pipe continuity test.
Do keep in mind though that the DPU control system will still work with only one data radio.
In the event you do forget about it, don't panic: you can go back to the Suppression position, wait at least 15 seconds then return to the Release position.
After getting the BP TEST soft key available, remember the guideline of having all locomotive consists having less than 40 CFM showing before attempting to execute.
At speeds above 20 mph, you will be okay with operation of a mixed consist. Below 20 mph and above 12 mph, the operator should nevertheless maintain awareness with minimum continuous speed and short time ratings operations for the DC units in the consist.
A. Because the air brake system pressures were the brake pipe pressure being higher than the equalizing reservior pressure.
By going from Trail to Lead Cutout, and then confirming the selection, it will then bring the equalizing reservoir pressure up to higher than the brake pipe pressure, so then when the Lead Cutin step is performed, you don't endure the air going into emergency.
I would like to thank everyone whose questions were this month's focus. May all continue to go well for you, your families and all of us.