FREDs

Does a FRED depend on the direction the train is traveling to do its job? In other words, if you ran a train "push-pull" with a locomotive at each end, could you just leave the FRED where it was or would you have to move it to the other end of the train before you sent the train back?

I live along the historic KC-Lincoln line of the Chicago, Burlington, and Quincy (once route of the Pioneer Zephyr), now part of Mr Buffett's railroad, the BNSF. We have a lot!! of coal movements with pushing locomotives on the rear, as well as some grain movements with same.

I'll have to look in detail, but I've not actually seen a true FRED device on the locomotives themselves recently. It's as though theu are leveraging the units' own internal cababilities...

Anyone else have actual knowledge?

It is not really clear what are asking but. A FRED, EOT, or whatever you want to call it just measures the air pressure and broadcasts it to the head end box MARRY. HEU, HOT or whatever you want to call it. It does not matter what direction it is going. However, the whole reason to have a FRED is to know how much pressure is on the REAR of your train, and it serves as a federally required marker light, and finally as an emergency brake application device.

If you are running a distributed power set up, the locomotive on the front controlling another unit at the rear of the train, a FRED is not needed, the DPU locomotive does all the jobs the FRED did

We called them markers or Telemetry units on conrail. If you have a push pull operation ,you can couple up to a car w/the unit still attached,(some models not all)but it won't operate because you cannot use the air hose connection. The marker will ,under normal conditions display a flashing red,detect movement,read air pressure and have the ability to dump the air from the rear of the train.

To add to what has been said about end of train devices, when operating helpers at the rear of the train, the helper engineer relays the brake pipe info to the head end. We are usually able to leave the EOT attached; air hoses connected from the helper unit(s) to the rear car. Usually the air hose on the EOT has a hook on it so one can hang it out of the way to prevent it from damage. I carry duct tape and zip ties and a multi-tool (Gerber)for such instances. Then when the helper is no longer needed the train stops, the helpers cut off, we reconnect the hose to the EOT and re-arm it if necessary. For brevity, I have left out information concerning operational rules.

This summer on a rail trail along the Pan Am Railway ROW in Northampton, MA, I have seen twenty or so freights with a red flag in the coupler of the last car instead of a Fred. The loco runs backward South pulling. Returning later, the loco is still in the "front" pushing the freight North and the flag is still in the coupler of the "last" car. The loco runs with all lights on.
Sometimes they use a real FRED.

Rich

FREDs have almost completely replaced cabooses (cabeese?). The idea behind them is to provide a means of dumping the air from the rear end (in addition to the engineer dumping the air from the loco), to provide an illuminated marker at night, and to provide a means of transmitting the air pressure reading from the rear end to the head end. Another function, rarely mentioned, is the ability to inform the engineer if the rear of the train is moving or stopped. This last function is valuable to let the engineer know when he can safely apply more power when starting the train. All of the functions were formerly performed by the rear end crew.

FRA rules define when the ability to dump the air from the rear end is required. It takes into account both tonnage and maximum length of grade and percentage of grade on the route transversed by the train. If the tonnage, percentage and length of grade is not exceeded, a FRED maybe replaced by a simple HVM (high visibility marker) that is actually just a red marker light. For operation during daylight hours, even that is not required. A red flag is sufficient.

The purpose of the red flag/light is to provide a positive indication to an observer that the car displaying it is, indeed the last car of the train. By knowing that, an observer would know that the rear portion of the train was not left on the track somewhere. It also tells them that the last car has passed a given spot. It is important for the engineer to know that, as when clearing a speed restriction, yard limit, or milepost location. The last is important when operating in Track Warrant Territory, as the dispatcher can then assign the track segment just cleared to a following train. The engineer can know the location of the rear of his train without a rear-end crew by measuring his train using the distance counter on the locomotive.

A train may reverse direction on a main line with dispatcher's permission, or if occupying the main line on a "work between" track warrant. But a crew member should be protecting the movement. This includes getting off and flagging road crossings. If the locomotive has "all lights on" it does not satisfy the requirement for headlights at road crossings if it is on the opposite end of the train.

Les