Can an Engineer use the Dynamic Brakes while a train is in full emergency for additional braking? Or is it pointless to try?
No, dynamic braking isn’t available while the engine is in emergency braking. When the wheels of the locomotive stop turning no more braking effort is possible from the locomotive. Also it is possible to generate too much braking effort from the locomotives causing the train to derail.
that is not 100% correct… depending on if the unit has been modified…the dynmaic brakes will work durning an emergancy brake appliaction (up intill the engins stop)… to to go into more detail for the orginal poster… when your train goes into emergancy eitehr by some mechanical issue like a derailment a broken air hose or the engineer puts the train into emergancy… changing the slack is the last thing you want to do while emergancy brakeing… it is a sure fire way to make what could me a just a minor situation into a major derailment… so you dont want to be putting it into dynamic brake… the best thing to do as far as train handleing goes…durning an emergancy…is to bail off the engin brakes and depending on what you are in (power or dynmaic) leave eveything where it is at and ride it out till it stops moving…and then being to assess the situation once you recover the air… unless of corse you can see from the cab that things behind you are well… very very bad…
csx engineer
Most new units have dynamic brake holding feature as long as I have less than 15 psi on the engine brakes, and I am bailing them off at the same time.
Rodney
For fun … The PCS drops out and is connected to the ER which drops out the governer and the GF. The DBI automatically bails off brake cylinder pressure when the DBI is picked up (in theory) . The IPS senses when the brake cylinder pressure is above 15 psi and drops out the dynamics (usually only on extended range. The BCPS does the same job and sometimes in concert with the IPS. In Emergency the ESS switch operates the sanders and if the engine is equipped with DB holding feature the BR overrides the PCR… I gotta lay down…
I resent your tone of voice!! How dare you get all technical on us like that! [swg]
Many thanks to all that replied to this.
Randy, I pretty much failed to understand the essence of your elaborate and detailed post explaining in fairly terse terms the process of something akin to what happens when braking happens (or fails to happen, depending upon the braking system in use) on a train that has combined emergency (or standard) braking systems used in conjunction with a dynamic braking system, both of which can be quite useful for retarding the forward motion of the train under the proper circumstances (which I won’t elaborate on at this point). [sigh]
I was having a bit of fun , the timing of the question was perfect considering that for the last 3 weeks I have been doing a bunch of training on both train handling with dynamic brakes, as well as some simple and some not so simple trouble shooting and repair training . I have literally been dreaming about dynamic brakes. (and lately even my food has been tasting like burnt brake grids) .
So I let you part way in to an inside joke.
The’re going to let you start driving those things with a train attached???
…gotta get my camera…
Ah … you misunderstand … I am the teacher grasshopper …
So…if I am able to take the reverser from your hand, will it be time for me to leave?
you’re dreaming about dynamic brakes? You need a vacation, me lad…
If you can take the reverser from my hand you are a human forklift !!! The reverser key … that’s another story …
Reverser KEY!? Oh, LA DE DAH, aren’t we elegant!? Down here in these parts we call the plastic part a reverser; the big clunky thing behind the high-voltage cabinet we called the reverser drum; in them-there new-fangled locos, who knows what they call them:
Part #24578-A23 EMD model 23 reversing mechanism activator enabling module?
And the plastic part we keep in our grips? That is the “type 28 locomotive directional function activating mechanism controlling feature-human interface device”.
And if I am a human forklift trying to remove something you are holding in your hand, then that makes you a __________?
Wait a minute … I’m from down around those parts as you have kindly reminded me on the occasions that I rip on cheeseheads… As for the rest of it … oh wait … my head just imploded.
As for the last part , that would make me an “idiot” for handling material that was too heavy . (I was actually hoping you would overlook that part of my statement)
You now need to fill out an ID Ten T form to substantiate your statement. [}:)]
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