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On one of the DPU trains which I was riding to qualify an engineer on this technique, he asked me a very good question: How is it that I have been able to deal with the same subject heading for all the years you have read this publication.
My answer to him was that like the rest of the world, we are always seeing a process in effect called change. It allows us to find out where we came from and which directions we are headed. Like so many of us see on a regular basis (and even talk about among one another), our experiences have been known to raise other questions regarding what to do in the event that similar situations should materialize themselves in future events.
It is from this that I, along with you, our readers and supporters, are able to put together this portion of our monthly get together. This month, I will be doing another questions and answers type of column, addressing actual events which have happened to myself and/or our contemporaries. As always, may the contents find their way to your level of satisfaction.
IFC AND E.O.T.D. RADIO BREAKS
Our first actual encounter occurred on March 31st of this year; the synopsis: I was working a CBTHS loaded coal train of the conventional format out of McAlester, Oklahoma. The train was coming into Whitesboro during a bad thunderstorm; a large lightning bolt appeared in the sky and then afterwards, the lead locomotive (a C44AC) displayed on the IFC screen, in yellow, an EOT COMM indicator and, in red, a no readout at the rear end pressure indicator.
What technique can you use to restore the system back to normal?
Answer: The first item to try is to go into the EOT Setup function on the IFC screen. Once you have accessed it, look at the box labeled COMM TEST and see if it has a Fail message displayed in it. If it does, then press the function key labeled for COMM TEST.
During the testing process, you will see the message Running displayed in the box. If all goes at it should, a message of Passed or OK should now come up in the box. This should bring back your readout. If it does not, then an inspection of the FRED device will need to be performed (who knows, maybe the lightning might have hit it, but wait until it is safe to do the inspection).
As those of us who deal with this equipment know, radio breaks are not uncommon with E.O.T.D. systems. But in the case of the integrated displays equipped locomotives, the system is a pass thru device that receives the radio signal from the rear end.
DPU Q & A
1. If you are getting a no load readout from a remote consist (locomotive), what items should you look at to determine the cause(s)?
A: First of all, look in the upper right corner of the control box console to see if you have the message of Run or Idle displayed. If it says Idle, then go to the Remote screen and press the RUN and then the EXECUTE keys to, in essence, "turn on the generator field switch" to the Remotes.
If you do have Run displayed, then look on the control box to see if you have a yellow Limited light displayed in the row of indicators, pull up the Remote screen to see if you have a condition message of Idle or Isolate. Should this be the case, then press the RUN and EXECUTE buttons to bring it back "on the line".
If these items all check out, then a physical inspection of the remote locomotive(s) must be made in order to make the determination of the problem. Information on conditions such as low water pressure tripping and things of this nature are not transmitted via the DPU control system.
2. This is a two part question: (A) Why do the readouts for the tractive effort meter and the control box console not matching up? (B) Why does it still show an AC Traction remote locomotive as having an amperage readout on the control box?
A: The readouts differential in the first question is caused by the model of current module which coordinates this process is not the right type. The input signal is correct, but then the module drags down that signal. The output signal that is then received by the control box console therefore is the dragged down version.
This correction will require both a software and hardware modification to the locomotive. An important note: This phenomenon does not occur with the DC model locomotives, so the output you get on the control box is correct.
The second question: The software program which is in use presently cannot "tell" the difference between an AC and a DC locomotive when it is operating as the remote consist leader. But so you don't get caught in a trap: The readout you are receiving is not in any way a translation of indicating that this is the amount of amperage that the locomotive is producing should it be at a given level of tractive effort meter output and/or perhaps, the given throttle/dynamic brake handle position. This is also a situation which is being addressed.
3. What are the causes for you getting a FAIL light on the control box console?
A. This question has what I term as dependent upon answers; the factor I'm referring to is the type of equipment on-board the locomotive. If the unit is equipped with the LOCOTROL III stand alone box and the EPIC air brake system, then any of the following conditions can cause this:
The control system loses communication with the E-Brake system.
The control box console loses communication with the system module.
There is a failure with one of the two magnet valves which is in use on the
E-Brake system. It most likely will be the No. 2 magnet valve, as it is the
one dedicated to DPU operations.
If the locomotive is outfitted with the stand alone box and the pneumatic air brake system, then the possible causes include:
The control box console has lost communication with the system module.
The locomotive has sustained an equalizing reservoir loopback error (In
other words, it is an equalizing reservoir failure).
A DPU system failure of these types will result in an emergency brake application to the train. To determine what your cause is, look on the SYSTEM screen and see what the newest message is in the event log. Unless the fault can be repaired (which in the field is probably not going to be possible), you would have to either replace the bad ordered locomotive with a new leader and relink the DPU control system, or you must reconfigure the train into a conventional format.
Keep this point in mind:
Although the locomotive might not have the DPU system now in a properly
working order, it does not mean that if you replace it as a leader, that it
cannot serve as a trailing unit for that particular consist, or function
normally as a conventional train lead unit, unless the air brake system is in
such a condition that in either route, you must confine it to trailing unit
status.
Now let's look at the new kid on the block; the Integrated Distributed Power system in use on the SD90/43AC locomotives. These units do not have a system fail light ; however, if you should incur a failure of the IDP system, the ICE screen should then have come up an event display which will outline what caused the failure.
The IDP system will go into a penalty brake application, unless the cause for the disruption is a failure of the E-Brake system, in which case the unit would then go into an emergency application. Because the IDP system arrangement does not have magnet valve detection to the E-Brake system, a maintenance facility would then have to go into the self-diagnostics system that the E-Brake has in order to determine the specific cause. Again, if the E-Brake failure occurs in the field, the locomotive would have to be made into a conventional trailing unit.
Regardless of the conditions causes, whenever you should incur a DPU system failure, notify the locomotive operations desk (alias Mr. Goodwrench) at the first available opportunity so that upon arrival at a major maintenance point, the locomotives may receive immediate attention.
THE C.L.O.P.S. SYSTEM
Among the reasons why I began this column was to inform affected parties about the what and how of equipment which is specified on foreign railroad motive power. In the case of this next feature, I came into knowledge of it when it activated on an SD45T-2R locomotive of the former Southern Pacific during a trip to McAlester, Oklahoma; the activation caused a shutdown of the locomotive.
It had a white light on the engine control panel illuminated that was labeled for compressor low oil shutdown. Here now is the background: The Southern Pacific units which underwent rebuilding at the Sacramento Locomotive Works facility had added to them a device referred to as C.L.O.P.S.; this is an acronym for Compressor Low Oil Pressure Sensor. When the device detects that the level of oil is too low to meet proper operating conditions for the compressor, it will send a warning signal to the control system to shut down the locomotive.
If upon finding out the compressor has the proper level of oil for operations, you can attempt a restart of the locomotive. Should it remain up and running, then it might have had an intermittent sensor problem of some type. But if after the restart, the locomotive shuts down again, then the problem is you have a faulty sensor.
A LOOK AHEAD
In next month's issue I'll be dealing with the performance qualities of the current edition of 4000 to 4400 horsepower AC Traction model locomotives as far as how do they perform in higher end speed service. Have a wonderful Memorial Day holidays, and remember that the Lord loves us all. Take care of yourselves and others.