MULTIPLE FREDS FOR LOW COST ELECTRONIC BRAKE CONTROL

[Euclid]

Wabtec has a chart that gives the emergency application stopping distance of several test trains, including one with ECP brakes.  They identify those test trains by the following designations:

 

ABDX

ABDW

ABD

ABDX+1 EOT-ES

ABDW+1 EOT-ES

ABD+1 EOT-ES

DIST. POWER +1 REMOTE

ABDX+2 EOT-ES

ABDW+2 EOT-ES

ABD+2 EOT-ES

ABDX+3 EOT-ES

ABDW+3 EOT-ES

ABD+3 EOT-ES

ECP

 

You can see that the last one is a train with ECP braking.  I am not sure what the first three designations mean.  But the next 10 designations appear to be the basic non-ECP train with various additions of EOT, and one with distributed power.  Does this reflect the multiple EOT application that Dave Klepper is suggesting?

 

This is shown with the stopping distances in slide #7 of this slideshow:

http://slideplayer.com/slide/236563/

[BigJim]

daveklepper

If controls for mid-train power are flexible so that when a train is cresting  a summit, the part going downhill can be in brake mode while power still is applied to the rear half (as an example) then two displays would obviously be required. 

I fail to see the purpose or even why you would want two EOT's. To the best of my knowledge, DPU's can be operated as separate sets. How often that this is done, I don't know. Back when I operated trains with Radio Units, the mid-train power was set up to mirror the head end power. (And if I remember correctly, even they could be set up as separate sets.) There was no problem with running them the same and no need for a second EOT.

[zugmann]

You really don't need any special way to mount an eotd in the middle of a train. They latch on to the side of the coupler, so they can be hung even if the cars are coupled.

[daveklepper]

At least the railroads will have a choice, take the newest and otherwise compliant cars out of service and equip them or add the EOTD-modifieds to existing consists, even while they are loading or unloading.

[dehusman]

You can't mount the MTD's (mid train devices) on the side of the car, that would provide clearance problems to structures and adjacent tracks.

You would have to have some way of connecting it to the air lines without the hose dragging on the track, but adjust to mulitple variations of mounting arrangements and still have flex to adjust to different draft gear arrangements.

How do you make a set out with this arrangement?  The set out has an MTD in it, if you turn the angle cock at the joint and come off with the head end, the EOT and rear MTD's going in emergency will put the head end in emergency.

[zugmann]

Irony is that unit trains will probably be the easiest (and first) to get ecp brakes.

[daveklepper]

I agree with all the comments.  This would not preclude having new cars built with all the stuff built-in and still compatible with the portable stuff.  Regarding the logistics, the first application would be for unit oil trains where the consist stays together and the FREDs would be removed only for the required inspection and testing cycle, which would probably affect the tankcars themselves.   The last application of this equipment would be when most of the total freightcar fleet has electronic control braking, many years from now, and this portable equipment will be used to make older cars usable with newer cars.

[zugmann]

Biggest issue I see is the time and logistics to mount and dismount multiple EOTDs on every train.

[caldreamer]

Redesigning the head end boxes is a very easy fix.  You wouldneed to change the software to accept multiple EOT information and keep track of what is going on.  No big deal for a good programmer..  

[zugmann]

 

EOTDs are mainly air-powered anymore. So that's already done.

Have to change the federal rules before you hang them off grab irons.  FRA is pretty picky about that - safety device and all.  (not a huge deal, but one more small issue to resolve).

Locomotive head end boxes are going to have to be redesigned to accept multiple EOT IDs.  Then will each one have to be in working order?  If one craps out and gives a front-to-rear no comm message, are you now restricted in your operations? All kinds of rules about EOTD failure currently on the books.  And then would each EOTD have to be tested to make sure it can dump the air from the head end?  That's required now. 

Again, not insurmountable objects, but objects none the less. And EOTDs aren't cheap, so by the time you do this - it may be cheaper just to install ECP brakes.

 

 

[daveklepper]

Taking this topic off the oil-train thread:    There would only be three displays in the cab.   Normally all FREDs give the same message, so one display would be sufficient.  If controls for mid-train power are flexible so that when a train is cresting  a summit, the part going downhill can be in brake mode while power still is applied to the rear half (as an example) then two displays would obviously be required.  A third display only lights up when there is an errant FRED that is not presenting data like the rest of its group, and the display tells which FRED it is.

Power for the FREDS might be charging batteries with small wind turbines that use the air draft under cars driving small alternators and rectifiers.

Again each FRED would connect to two air hoses as well as joining them mechanicaly.  Each would hang off of a grab iron on the end of either car and would both transmit data and respond to brake commands of the engineer.