Eastern Railroad Discussion > Fred ,End of train device

Where can I read about "Freds",End of trains devices,how they work when a brake aplication is to be made etc?
Name of different makers of such devices?

Basically, Fred sits back there and is always talking with HODT (head of train device). It tells the engineer such things as movement and brake pressure. When the fred senses a change in brake pipe pressure, it tell the head end device of this change.
They basically work just like the internet except, the elctronic singals travel via the radio and not by a phone line.

The major makers of EOTs here in the states are, USS (United Signal Systems) and Pulse. Norfolk Southern used to make their own EOTs but, got out of that when they aquiered Conrail.

The E.O.T is basically a transmitter. The H.O.T. is the reciever for
the EOT. At an initial terminal where we have to make up a train we
are required to hang an EOT on the rear of our train and do a brake
test. Once some one hangs the EOT on the rear car then he will tell
me what the number is on the EOT unit. I enter this number into the
HOT box on the lead motor. If everything go's right then the HOT &
EOT will form a communication link. The HOT will read "LINKED". We
then turn in the air to be sure there is air on the rear car. At this
time we perform what we call a "dump test". The air is cut out on the
EOT and when I get the ok I throw a toggle switch on the HOT box,
placing the EOT in emergency, exhausting the trapped air in the EOT.
This tells us that the EOT is working properly.
Then I check to be sure there is proper air pressure on the rear
by checking the readout on the HOT. When I draw down the air for a
brake test, the EOT let's me see the air pressure drop on the rear
car. When the test is finished I release the brakes on the train
and watch the pressure climb on the EOT. This tells me that the brakes are releasing on the rear.
When I'm going down the road and my EOT reading says the pressure
is slowly dropping on the rear then I know we have a leak somewhere
in the trainline and we then stop and inspect the train.
I hope this will help you understand the workings of the EOT's and
HOT's.

C.B.

I thougt that all brake settings were made throuh the Fred and releasing were made on the locomotive.
I like to see a device where the brakes can be applyed from the rear and releeses from the front.
Are such devices in use in the US?I am not thinking of EP brakes.

USS is Union Switch & Signal.

If you applied the brakes from the rear,the train would be torn into many pieces.

Bengt wrote:
>
> I thougt that all brake settings were made throuh the Fred and
> releasing were made on the locomotive.

No. All brake applications and releases are made on the locomotive, with the exception of an emergency, which can be applied from the EOT on command from the engineer. Normally, the emergency would be made at the head end.

> I like to see a device where the brakes can be applied from the
> rear and releases from the front.
> Are such devices in use in the US? I am not thinking of EP brakes.

There is such a system, but I don't think many have been sold so far. It is made up of a box similar to the EOT with a radio link to the locomotive. The boxes will mimic brake applications made on the locomotive to speed up the application of both service and emergency brakes in the train. One or more of these boxes can be placed at a number of locations in the train, where they are connected to the brake pipe.